This document discusses various packaging considerations and types for VLSI devices. It covers key design parameters like number of terminals, electrical, thermal, and reliability considerations. It then describes various package types including through hole packages, surface mount packages, flip chip packages, chip size packages, multi-chip modules, and 3D packaging. The goal of packaging is to protect the chip, provide electrical connections, and dissipate heat while meeting requirements for performance, cost, reliability, and manufacturability.
This document discusses packaging considerations for VLSI devices. It covers package types like through-hole packages, surface-mounted packages, flip chip packages, and chip-scale packages. Key package design considerations include the number of terminals, electrical design to minimize signal degradation, thermal design to dissipate heat, reliability over temperature cycles, and testability to ensure quality. The ideal package is compact with low-inductance connections to transfer heat efficiently while withstanding stresses.
A Study on Stochastic Thermal Characterization of Electronic PackagesIJERA Editor
Insofar as the electronics can be found now in several applications of multiple domains, we have tried to
highlight in this study that, those systems must be based on unquestionable reliability and meet the needs of the
external environment. Starting from the unit "°c / w" concerning the thermal resistance from the gap between
junction temperature and a reference temperature, we have tried to compare the thermal performance of
electronic packages taking into consideration the thermal management. Our approach is based on the Monte
Carlo simulation and the stochastic characterization of the QFN. From the norm of normalization, we have
obtained standardized data sheets allowing accurate comparisons of the thermal performance of electronic
packages as produced by different manufacturers. Our numerical model through simulation, prototyping
concerning the design involves the JEDEC recommendations, which we consider a very interesting alternative.
Through the deterministic analysis, we conducted an analysis from the Matlab program parameters, which
control the Ansys software, the results were processed by statistical techniques to evaluate the times of the
thermal resistance of the QFN. That is why we must consider the electronic package (encapsulating the
integrated circuit), through the printed circuit board (PCB) to ensure the junction temperature maintenance and
avoid the dissipation of the heat. Also our process was based on the union of the finite element method to the
Monte Carlo simulation and stochastic characterization of the QFN.
Keywords: Electronic package; Finite element method; printed
This document discusses package design considerations and types of semiconductor packages. It covers key factors in package design like the number of terminals, electrical, thermal, and reliability requirements. The main package types discussed are through-hole packages like DIP and QFP, and surface mount packages like SOP, PLCC, and LCCC. Through-hole packages use precision holes drilled through the board while surface mount packages solder directly to the board surface.
THERMAL MODELING AND ANALYSIS OF 3- DIMENSINAL MEMORY INTEGRATION cscpconf
Moore's law describes a long-term trend in the history of computing hardware. The
conventional methods have reached his limits so new fields has to be exploited. Such a concept
is 3-Dimensional integration where the components are arranged in 3D plane. This
arrangement can increase the package density of devices. The successful construction of 3D
memory can lead to a new revolution in designing and manufacturing high performance
microprocessor system on chip. The major problem is the increased temperature effects. It’s
important to develop an accurate power profile extraction methodology to design 3D memory.
The total power dissipation includes static and dynamic component. In this paper the static
power dissipation of the memory cell is analysed and is used to accurately model the inter-layer
thermal effects for 3D memory stack. Then packaging of the chip is considered and modelled
using an architecture level simulator. This modelling is intended to analyse the thermal effects
of 3D memory, its reliability and lifetime of the chip with greater accuracy.
3D ICs can alleviate problems caused by long interconnects in traditional 2D chips by stacking layers and using short vertical interconnects between layers. This approach improves chip performance and density. However, 3D ICs also introduce thermal and reliability challenges due to heat dissipation issues and stresses between layers that must be addressed. Rent's rule can be used to estimate performance improvements from 3D architectures by analyzing reductions in total interconnect length.
A Review on Thermal Properties of Epoxy Composites as Thermal Interface MaterialIRJET Journal
This document reviews the use of epoxy composites as thermal interface materials. Thermal management is critical for electronic devices due to increasing power densities. Thermal interface materials are used to fill air gaps and improve heat transfer between electronic components and heat sinks. Epoxy resins are widely used as thermal interface materials due to their excellent properties. However, epoxy resins have low inherent thermal conductivity. Adding high thermal conductivity filler materials to epoxy can improve its thermal conductivity and make it a more effective thermal interface material. The document discusses different types of fillers used and their effect on the thermal properties of epoxy composites.
This document discusses warpage of microelectronic packages. It begins with an introduction to the importance of controlling warpage, especially in package-on-package configurations where tight warpage specifications are required. The key factors that influence warpage are identified as the die size/thickness, substrate properties and thickness, and underfill material properties. The document then examines warpage fundamentals using the bimetallic strip theory in 2D and finite element modeling in 3D. It identifies glass transition temperature, coefficient of thermal expansion, viscosity, and filler content as important underfill properties for controlling warpage. Solutions for reducing warpage through underfill design and other techniques are proposed.
This document summarizes reliability testing performed on multilayer ceramic (MLC) decoupling capacitors with C4 interconnects. It discusses three types of capacitors - DCAP, LICA, and LP-LICA - which differ in size, capacitance, and number of plates. Extensive reliability stress tests were conducted, including thermal shock, moisture resistance, thermal cycling, high temperature bias, and temperature humidity bias. No failures were observed for any capacitors during the tests, and all electrical parameters remained stable, demonstrating the reliability of the C4 interconnect technology for MLC decoupling capacitors.
This document discusses packaging considerations for VLSI devices. It covers package types like through-hole packages, surface-mounted packages, flip chip packages, and chip-scale packages. Key package design considerations include the number of terminals, electrical design to minimize signal degradation, thermal design to dissipate heat, reliability over temperature cycles, and testability to ensure quality. The ideal package is compact with low-inductance connections to transfer heat efficiently while withstanding stresses.
A Study on Stochastic Thermal Characterization of Electronic PackagesIJERA Editor
Insofar as the electronics can be found now in several applications of multiple domains, we have tried to
highlight in this study that, those systems must be based on unquestionable reliability and meet the needs of the
external environment. Starting from the unit "°c / w" concerning the thermal resistance from the gap between
junction temperature and a reference temperature, we have tried to compare the thermal performance of
electronic packages taking into consideration the thermal management. Our approach is based on the Monte
Carlo simulation and the stochastic characterization of the QFN. From the norm of normalization, we have
obtained standardized data sheets allowing accurate comparisons of the thermal performance of electronic
packages as produced by different manufacturers. Our numerical model through simulation, prototyping
concerning the design involves the JEDEC recommendations, which we consider a very interesting alternative.
Through the deterministic analysis, we conducted an analysis from the Matlab program parameters, which
control the Ansys software, the results were processed by statistical techniques to evaluate the times of the
thermal resistance of the QFN. That is why we must consider the electronic package (encapsulating the
integrated circuit), through the printed circuit board (PCB) to ensure the junction temperature maintenance and
avoid the dissipation of the heat. Also our process was based on the union of the finite element method to the
Monte Carlo simulation and stochastic characterization of the QFN.
Keywords: Electronic package; Finite element method; printed
This document discusses package design considerations and types of semiconductor packages. It covers key factors in package design like the number of terminals, electrical, thermal, and reliability requirements. The main package types discussed are through-hole packages like DIP and QFP, and surface mount packages like SOP, PLCC, and LCCC. Through-hole packages use precision holes drilled through the board while surface mount packages solder directly to the board surface.
THERMAL MODELING AND ANALYSIS OF 3- DIMENSINAL MEMORY INTEGRATION cscpconf
Moore's law describes a long-term trend in the history of computing hardware. The
conventional methods have reached his limits so new fields has to be exploited. Such a concept
is 3-Dimensional integration where the components are arranged in 3D plane. This
arrangement can increase the package density of devices. The successful construction of 3D
memory can lead to a new revolution in designing and manufacturing high performance
microprocessor system on chip. The major problem is the increased temperature effects. It’s
important to develop an accurate power profile extraction methodology to design 3D memory.
The total power dissipation includes static and dynamic component. In this paper the static
power dissipation of the memory cell is analysed and is used to accurately model the inter-layer
thermal effects for 3D memory stack. Then packaging of the chip is considered and modelled
using an architecture level simulator. This modelling is intended to analyse the thermal effects
of 3D memory, its reliability and lifetime of the chip with greater accuracy.
3D ICs can alleviate problems caused by long interconnects in traditional 2D chips by stacking layers and using short vertical interconnects between layers. This approach improves chip performance and density. However, 3D ICs also introduce thermal and reliability challenges due to heat dissipation issues and stresses between layers that must be addressed. Rent's rule can be used to estimate performance improvements from 3D architectures by analyzing reductions in total interconnect length.
A Review on Thermal Properties of Epoxy Composites as Thermal Interface MaterialIRJET Journal
This document reviews the use of epoxy composites as thermal interface materials. Thermal management is critical for electronic devices due to increasing power densities. Thermal interface materials are used to fill air gaps and improve heat transfer between electronic components and heat sinks. Epoxy resins are widely used as thermal interface materials due to their excellent properties. However, epoxy resins have low inherent thermal conductivity. Adding high thermal conductivity filler materials to epoxy can improve its thermal conductivity and make it a more effective thermal interface material. The document discusses different types of fillers used and their effect on the thermal properties of epoxy composites.
This document discusses warpage of microelectronic packages. It begins with an introduction to the importance of controlling warpage, especially in package-on-package configurations where tight warpage specifications are required. The key factors that influence warpage are identified as the die size/thickness, substrate properties and thickness, and underfill material properties. The document then examines warpage fundamentals using the bimetallic strip theory in 2D and finite element modeling in 3D. It identifies glass transition temperature, coefficient of thermal expansion, viscosity, and filler content as important underfill properties for controlling warpage. Solutions for reducing warpage through underfill design and other techniques are proposed.
This document summarizes reliability testing performed on multilayer ceramic (MLC) decoupling capacitors with C4 interconnects. It discusses three types of capacitors - DCAP, LICA, and LP-LICA - which differ in size, capacitance, and number of plates. Extensive reliability stress tests were conducted, including thermal shock, moisture resistance, thermal cycling, high temperature bias, and temperature humidity bias. No failures were observed for any capacitors during the tests, and all electrical parameters remained stable, demonstrating the reliability of the C4 interconnect technology for MLC decoupling capacitors.
A 2D MODELLING OF THERMAL HEAT SINK FOR IMPATT AT HIGH POWER MMW FREQUENCYcscpconf
A very useful method of formulating the Total Thermal Resistance of ordinary mesa structure of DDR IMPATT diode oscillators are presented in this paper. The main aim of this paper is to provide a 2D model for Si and SiC based IMPATT having different heat sinks (Type IIA diamond and copper) at high power MMW frequency and study the characteristics of Total thermal resistance versus diode diameter for both the devices. Calculations of Total thermal resistances associated with different DDR IMPATT diodes with different base materials
operating at 94 GHz (W-Band) are included in this paper using the author’s developed formulation for both type-IIA diamond and copper semi-infinite heat sinks separately. Heat
Sinks are designed using both type-IIA diamond and copper for all those diodes to operate near 500 K (which is well below the burn-out temperatures of all those base materials) for CW
steady state operation. Results are provided in the form of necessary graphs and tables.
A Novel Methodlogy For Thermal Ananalysis & 3-Dimensional Memory Integrationijait
The semiconductor industry is reaching a fascinating confluence in several evolutionary trends that will likely lead to a number of revolutionary changes in the design, implementation, scaling, and the use of computer systems. However, recently Moore’s law has come to a stand-still since device scaling beyond 65 nm is not practical. 2D integration has problems like memory latency, power dissipation, and large foot-print. 3D technology comes as a solution to the problems posed by 2D integration. The utilization of 3D is limited by the problem of temperature crisis. It is important to develop an accurate power profile extraction methodology to design 3D structure. In this paper, design of 3D integration of memory is considered and hence the static power dissipation of the memory cell is analysed in transistor level and is used to accurately model the inter-layer thermal effects for 3D memory stack. Subsequently, packaging of the chip is considered and modelled using an architecture level simulator. This modelling is intended to analyse the thermal effects of 3D memory, its reliability and lifetime of the chip, with greater accuracy
A NOVEL METHODLOGY FOR THERMAL ANANALYSIS & 3-DIMENSIONAL MEMORY INTEGRATION ijait
The semiconductor industry is reaching a fascinating confluence in several evolutionary trends that will likely lead to a number of revolutionary changes in the design, implementation, scaling, and the use of computer systems. However, recently Moore’s law has come to a stand-still since device scaling beyond
65 nm is not practical. 2D integration has problems like memory latency, power dissipation, and large foot-print. 3D technology comes as a solution to the problems posed by 2D integration. The utilization of 3D is limited by the problem of temperature crisis. It is important to develop an accurate power profile
extraction methodology to design 3D structure. In this paper, design of 3D integration of memory is considered and hence the static power dissipation of the memory cell is analysed in transistor level and is used to accurately model the inter-layer thermal effects for 3D memory stack. Subsequently, packaging
of the chip is considered and modelled using an architecture level simulator. This modelling is intended to analyse the thermal effects of 3D memory, its reliability and lifetime of the chip, with greater accuracy.
The document discusses capacitance variation in MEMS capacitors based on plate area, distance between plates, and different dielectric materials. It outlines the research significance, methodology, experimental details, results and discussion, and conclusion. The results show that capacitance increases with larger plate area, smaller distance between plates, and dielectric materials with higher relative dielectric constants. The capacitance variation can be utilized in applications such as wireless communications, sensing, and electronics.
IEEE Research Article - Polymeric Packaging of High Power Semi-ConductorsKashif Kamran Ahmad
This document discusses the development of a polymeric packaging demonstration for high power semiconductor thyristor devices used in high voltage direct current transmission schemes. It examines different housing design concepts and materials selection to develop a 50mm prototype polymeric package. Testing of the manufactured prototype included temperature cycling reliability studies and thermo-mechanical simulations to assess the integrity of the housing design and selected polymer material. The research aims to evaluate whether a polymeric housing can provide comparable performance and reliability to traditional ceramic-based packages.
Analysis of polymer polymethyl metha-acralyte and single-wall cnt compositesIAEME Publication
This document discusses analysis of polymer composites made of polymethyl-metha-acrylate (PMMA) and single-wall carbon nanotubes (SWCNTs). Modulation calorimetry techniques such as ACC and MDSC are used to study the thermal properties and glass transition dynamics of the composites. The ACC results show that the effective thermal conductivity of the composites increases with higher SWCNT content, agreeing with theoretical models. MDSC indicates the SWCNTs may quench glassy structural dynamics in PMMA and reduce the hysteresis between heating and cooling curves. Overall the study analyzes the thermal properties of PMMA-SWCNT composites using advanced calorimetry methods.
IRJET- Development of MGO-EPOXY Composites with Enhanced Thermal ConductivityIRJET Journal
This document discusses the development of MgO-epoxy composites with enhanced thermal conductivity. Researchers successfully prepared MgO-epoxy composites by infiltrating magnesium oxide (MgO) powder into epoxy resin. Testing found that thermal conductivity increased with MgO content, reaching a maximum of 0.207 W/(mK) at 20 wt% MgO, higher than neat epoxy. This demonstrates a potential method for manufacturing epoxy composites with extremely high thermal conductivity suitable for electronic device packaging and heat dissipation applications. The document provides background on thermal interface materials and discusses various ceramic fillers used to increase the thermal conductivity of polymer composites.
This document discusses package fabrication technology. It begins by defining packaging as the technology required between an integrated circuit and the system level. There are three main levels of packaging - chip, board, and system level. The major functions of packaging are signal distribution, power distribution, heat dissipation, and protection from mechanical, chemical and electromagnetic stresses. Package fabrication technologies include refractory ceramic and molded plastic, and are either through-hole or surface mount. Key aspects covered include chip-to-package interconnections using wire bonding, TAB, flip chip, and chip-on-board approaches. 3D packaging technology is also summarized.
Thermal monitoring of cable circuits and grid operators' use of dynamic ratin...Power System Operation
At present, due to more uncertainty in the energy
market and increasing loads in the power grids, a
real-time thermal rating (RTTR) system and other
measurement techniques aid the asset manager in
making optimal decisions in operational and planning
investments. Based on measurement, a grid operator
can on the one hand decide if a hotspot in network
should be removed to increase the capacity or if the
hotspot should be managed with a RTTR system.
This enables the Operator to understand the load and
overload possibilities in real time and into the near
future (few hours or days). The currently predominant technology for thermal measurement on power cables is DTS (Distributed Temperature Sensing) often used in combination with
This document describes thermal analysis of an electronic package using TAMS and TNETFA software tools. TAMS and TNETFA are FORTRAN codes that use lumped modeling to analyze heat transfer through multilayer structures like printed circuit boards. The document details the theoretical basis of the codes and provides an example analysis of a printed circuit board with 34 heat-generating components. The board is modeled with both 1-resistor and 2-resistor component models in TNETFA and results are compared to a commercial software, showing good agreement. The analysis provides insight into the thermal behavior of the electronic package and components under different operating conditions.
Undergrounding high voltage_electricity_transmission_lines_the_technical_issu...Ivan Rojas Soliz
Undergrounding high voltage electricity transmission lines has several technical challenges compared to overhead lines. Underground cables require robust insulation unlike overhead lines which use air insulation. They also generate more heat that must be dissipated through larger cable size or cooling systems. Installation methods for underground cables like direct burial or tunneling require extensive excavation and have higher capital costs than equivalent overhead lines. Maintenance and repairs of underground cables are also more complex and time consuming. While undergrounding reduces visual impacts, it has other environmental and planning considerations regarding land use restrictions and potential disturbances during installation and maintenance.
This document summarizes an experiment to measure the out-of-plane thermal conductivity of flexible substrate materials like polyethylene naphthalate (PEN) and polyethylene teraphthalate (PET). A steady-state method is used where a heat flux is applied through one copper block in contact with the substrate, and the temperature difference across the substrate is measured. Thermal conductivity values are determined from the temperature differences and heat fluxes for substrates of varying thicknesses. The results indicate low thermal conductivity for flexible substrates, which could challenge thermal management in flexible electronics due to limited heat spreading and lack of active cooling options.
Electrical signal interference minimization using appropriate core material f...IJECEIAES
As demand for smaller, quicker, and more powerful devices rises, Moore's law is strictly followed. The industry has worked hard to make little devices that boost productivity. The goal is to optimize device density. Scientists are reducing connection delays to improve circuit performance. This helped them understand three-dimensional integrated circuit (3D IC) concepts, which stack active devices and create vertical connections to diminish latency and lower interconnects. Electrical involvement is a big worry with 3D integrates circuits. Researchers have developed and tested through silicon via (TSV) and substrates to decrease electrical wave involvement. This study illustrates a novel noise coupling reduction method using several electrical involvement models. A 22% drop in electrical involvement from wave-carrying to victim TSVs introduces this new paradigm and improves system performance even at higher THz frequencies.
Effects of backfilling on cable ampacity analyzed with the finite element methodthinknice
This document describes a study analyzing how cable ampacity is affected by different backfill configurations using finite element modeling. It begins by reviewing existing methods for calculating external thermal resistance from standards like IEEE and extensions by other researchers. The finite element method allows modeling situations with varying soil thermal resistivities not addressed by standards. Results show ampacity is highly sensitive to soil thermal properties. The study then analyzes effects on ampacity from varying backfill quantity, shape, location and engineered backfill using finite element modeling to better understand impacts in non-standardized situations.
Probe Card Manufacturing Paving the Way for Semiconductor Testing ExcellenceSemi Probes Inc
The document discusses the manufacturing process of probe cards, which play a crucial role in testing integrated circuits on semiconductor wafers. It involves several intricate steps including designing the probe card layout, fabricating the substrate and probe needles, depositing interconnects, and extensive quality testing. Advancements like microfabrication techniques, new materials, and multi-device testing have enhanced probe card performance and manufacturing efficiency. Precisely engineered probe cards are essential for ensuring quality and reliability in the semiconductor industry.
Technical Bulletin 1128A Mechanical Insulation In Typical Refrigeration Appli...Dyplast Products
The document discusses key considerations for selecting insulation materials for refrigeration applications. It states that thermal conductivity (k-factor) and water vapor transmission (WVT) are the most important properties to consider, as they significantly impact energy costs and system performance over the life of the insulation. Polyisocyanurate insulation has the best combination of k-factor and WVT compared to other common insulants like extruded polystyrene and fiberglass. While capital costs are a factor, prioritizing k-factor and WVT will reduce operating costs and risks of failure in the long run.
Nowadays, mobile consumer electronics devices integrate various wireless interfaces like WIFI, Bluetooth, GPRS and GPS. Various approaches exist to protect the wireless interfaces against ESD stress. In recent years, researchers have focused on so‐called 'co‐design' techniques to solve both functional and protection constraints together which requires both RF and ESD design skills. However many IC designers still prefer to work with 'plug‐n‐play' protection concepts where the ESD clamps exhibit low parasitic capacitance, low series resistance and low leakage. This paper presents measurement results of 3 different SCR based protection approaches that exhibit high Q‐factor and low and stable parasitic capacitance over a broad voltage and frequency range. The clamps are used for protection of LNA circuits in 90nm and 40nm Low Power (LP) CMOS technologies.
IRJET- Geometrical Optimization of Fins for Effective Heat Transfer using CFD...IRJET Journal
This document discusses geometrical optimization of fins for effective heat transfer using computational fluid dynamics (CFD) analysis. It aims to study the optimization of fin profiles for electronic devices with innovative shapes, particularly analyzing Y-shaped fins. CFD analysis is performed using ANSYS Fluent to analyze heat exchange behavior and plot temperature contours for T-shaped and Y-shaped aluminum fins surrounded by air. The analysis varies the angle between the arms of fins from T-shape to Y-shape under dimensional constraints to compare configurations and validate a new optimization criterion. The modeling is done in Creo and analysis in ANSYS Fluent to optimize fin geometry for maximum heat transfer and minimum pressure drop.
Assessment and Planning in Educational technology.pptxKavitha Krishnan
In an education system, it is understood that assessment is only for the students, but on the other hand, the Assessment of teachers is also an important aspect of the education system that ensures teachers are providing high-quality instruction to students. The assessment process can be used to provide feedback and support for professional development, to inform decisions about teacher retention or promotion, or to evaluate teacher effectiveness for accountability purposes.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
A 2D MODELLING OF THERMAL HEAT SINK FOR IMPATT AT HIGH POWER MMW FREQUENCYcscpconf
A very useful method of formulating the Total Thermal Resistance of ordinary mesa structure of DDR IMPATT diode oscillators are presented in this paper. The main aim of this paper is to provide a 2D model for Si and SiC based IMPATT having different heat sinks (Type IIA diamond and copper) at high power MMW frequency and study the characteristics of Total thermal resistance versus diode diameter for both the devices. Calculations of Total thermal resistances associated with different DDR IMPATT diodes with different base materials
operating at 94 GHz (W-Band) are included in this paper using the author’s developed formulation for both type-IIA diamond and copper semi-infinite heat sinks separately. Heat
Sinks are designed using both type-IIA diamond and copper for all those diodes to operate near 500 K (which is well below the burn-out temperatures of all those base materials) for CW
steady state operation. Results are provided in the form of necessary graphs and tables.
A Novel Methodlogy For Thermal Ananalysis & 3-Dimensional Memory Integrationijait
The semiconductor industry is reaching a fascinating confluence in several evolutionary trends that will likely lead to a number of revolutionary changes in the design, implementation, scaling, and the use of computer systems. However, recently Moore’s law has come to a stand-still since device scaling beyond 65 nm is not practical. 2D integration has problems like memory latency, power dissipation, and large foot-print. 3D technology comes as a solution to the problems posed by 2D integration. The utilization of 3D is limited by the problem of temperature crisis. It is important to develop an accurate power profile extraction methodology to design 3D structure. In this paper, design of 3D integration of memory is considered and hence the static power dissipation of the memory cell is analysed in transistor level and is used to accurately model the inter-layer thermal effects for 3D memory stack. Subsequently, packaging of the chip is considered and modelled using an architecture level simulator. This modelling is intended to analyse the thermal effects of 3D memory, its reliability and lifetime of the chip, with greater accuracy
A NOVEL METHODLOGY FOR THERMAL ANANALYSIS & 3-DIMENSIONAL MEMORY INTEGRATION ijait
The semiconductor industry is reaching a fascinating confluence in several evolutionary trends that will likely lead to a number of revolutionary changes in the design, implementation, scaling, and the use of computer systems. However, recently Moore’s law has come to a stand-still since device scaling beyond
65 nm is not practical. 2D integration has problems like memory latency, power dissipation, and large foot-print. 3D technology comes as a solution to the problems posed by 2D integration. The utilization of 3D is limited by the problem of temperature crisis. It is important to develop an accurate power profile
extraction methodology to design 3D structure. In this paper, design of 3D integration of memory is considered and hence the static power dissipation of the memory cell is analysed in transistor level and is used to accurately model the inter-layer thermal effects for 3D memory stack. Subsequently, packaging
of the chip is considered and modelled using an architecture level simulator. This modelling is intended to analyse the thermal effects of 3D memory, its reliability and lifetime of the chip, with greater accuracy.
The document discusses capacitance variation in MEMS capacitors based on plate area, distance between plates, and different dielectric materials. It outlines the research significance, methodology, experimental details, results and discussion, and conclusion. The results show that capacitance increases with larger plate area, smaller distance between plates, and dielectric materials with higher relative dielectric constants. The capacitance variation can be utilized in applications such as wireless communications, sensing, and electronics.
IEEE Research Article - Polymeric Packaging of High Power Semi-ConductorsKashif Kamran Ahmad
This document discusses the development of a polymeric packaging demonstration for high power semiconductor thyristor devices used in high voltage direct current transmission schemes. It examines different housing design concepts and materials selection to develop a 50mm prototype polymeric package. Testing of the manufactured prototype included temperature cycling reliability studies and thermo-mechanical simulations to assess the integrity of the housing design and selected polymer material. The research aims to evaluate whether a polymeric housing can provide comparable performance and reliability to traditional ceramic-based packages.
Analysis of polymer polymethyl metha-acralyte and single-wall cnt compositesIAEME Publication
This document discusses analysis of polymer composites made of polymethyl-metha-acrylate (PMMA) and single-wall carbon nanotubes (SWCNTs). Modulation calorimetry techniques such as ACC and MDSC are used to study the thermal properties and glass transition dynamics of the composites. The ACC results show that the effective thermal conductivity of the composites increases with higher SWCNT content, agreeing with theoretical models. MDSC indicates the SWCNTs may quench glassy structural dynamics in PMMA and reduce the hysteresis between heating and cooling curves. Overall the study analyzes the thermal properties of PMMA-SWCNT composites using advanced calorimetry methods.
IRJET- Development of MGO-EPOXY Composites with Enhanced Thermal ConductivityIRJET Journal
This document discusses the development of MgO-epoxy composites with enhanced thermal conductivity. Researchers successfully prepared MgO-epoxy composites by infiltrating magnesium oxide (MgO) powder into epoxy resin. Testing found that thermal conductivity increased with MgO content, reaching a maximum of 0.207 W/(mK) at 20 wt% MgO, higher than neat epoxy. This demonstrates a potential method for manufacturing epoxy composites with extremely high thermal conductivity suitable for electronic device packaging and heat dissipation applications. The document provides background on thermal interface materials and discusses various ceramic fillers used to increase the thermal conductivity of polymer composites.
This document discusses package fabrication technology. It begins by defining packaging as the technology required between an integrated circuit and the system level. There are three main levels of packaging - chip, board, and system level. The major functions of packaging are signal distribution, power distribution, heat dissipation, and protection from mechanical, chemical and electromagnetic stresses. Package fabrication technologies include refractory ceramic and molded plastic, and are either through-hole or surface mount. Key aspects covered include chip-to-package interconnections using wire bonding, TAB, flip chip, and chip-on-board approaches. 3D packaging technology is also summarized.
Thermal monitoring of cable circuits and grid operators' use of dynamic ratin...Power System Operation
At present, due to more uncertainty in the energy
market and increasing loads in the power grids, a
real-time thermal rating (RTTR) system and other
measurement techniques aid the asset manager in
making optimal decisions in operational and planning
investments. Based on measurement, a grid operator
can on the one hand decide if a hotspot in network
should be removed to increase the capacity or if the
hotspot should be managed with a RTTR system.
This enables the Operator to understand the load and
overload possibilities in real time and into the near
future (few hours or days). The currently predominant technology for thermal measurement on power cables is DTS (Distributed Temperature Sensing) often used in combination with
This document describes thermal analysis of an electronic package using TAMS and TNETFA software tools. TAMS and TNETFA are FORTRAN codes that use lumped modeling to analyze heat transfer through multilayer structures like printed circuit boards. The document details the theoretical basis of the codes and provides an example analysis of a printed circuit board with 34 heat-generating components. The board is modeled with both 1-resistor and 2-resistor component models in TNETFA and results are compared to a commercial software, showing good agreement. The analysis provides insight into the thermal behavior of the electronic package and components under different operating conditions.
Undergrounding high voltage_electricity_transmission_lines_the_technical_issu...Ivan Rojas Soliz
Undergrounding high voltage electricity transmission lines has several technical challenges compared to overhead lines. Underground cables require robust insulation unlike overhead lines which use air insulation. They also generate more heat that must be dissipated through larger cable size or cooling systems. Installation methods for underground cables like direct burial or tunneling require extensive excavation and have higher capital costs than equivalent overhead lines. Maintenance and repairs of underground cables are also more complex and time consuming. While undergrounding reduces visual impacts, it has other environmental and planning considerations regarding land use restrictions and potential disturbances during installation and maintenance.
This document summarizes an experiment to measure the out-of-plane thermal conductivity of flexible substrate materials like polyethylene naphthalate (PEN) and polyethylene teraphthalate (PET). A steady-state method is used where a heat flux is applied through one copper block in contact with the substrate, and the temperature difference across the substrate is measured. Thermal conductivity values are determined from the temperature differences and heat fluxes for substrates of varying thicknesses. The results indicate low thermal conductivity for flexible substrates, which could challenge thermal management in flexible electronics due to limited heat spreading and lack of active cooling options.
Electrical signal interference minimization using appropriate core material f...IJECEIAES
As demand for smaller, quicker, and more powerful devices rises, Moore's law is strictly followed. The industry has worked hard to make little devices that boost productivity. The goal is to optimize device density. Scientists are reducing connection delays to improve circuit performance. This helped them understand three-dimensional integrated circuit (3D IC) concepts, which stack active devices and create vertical connections to diminish latency and lower interconnects. Electrical involvement is a big worry with 3D integrates circuits. Researchers have developed and tested through silicon via (TSV) and substrates to decrease electrical wave involvement. This study illustrates a novel noise coupling reduction method using several electrical involvement models. A 22% drop in electrical involvement from wave-carrying to victim TSVs introduces this new paradigm and improves system performance even at higher THz frequencies.
Effects of backfilling on cable ampacity analyzed with the finite element methodthinknice
This document describes a study analyzing how cable ampacity is affected by different backfill configurations using finite element modeling. It begins by reviewing existing methods for calculating external thermal resistance from standards like IEEE and extensions by other researchers. The finite element method allows modeling situations with varying soil thermal resistivities not addressed by standards. Results show ampacity is highly sensitive to soil thermal properties. The study then analyzes effects on ampacity from varying backfill quantity, shape, location and engineered backfill using finite element modeling to better understand impacts in non-standardized situations.
Probe Card Manufacturing Paving the Way for Semiconductor Testing ExcellenceSemi Probes Inc
The document discusses the manufacturing process of probe cards, which play a crucial role in testing integrated circuits on semiconductor wafers. It involves several intricate steps including designing the probe card layout, fabricating the substrate and probe needles, depositing interconnects, and extensive quality testing. Advancements like microfabrication techniques, new materials, and multi-device testing have enhanced probe card performance and manufacturing efficiency. Precisely engineered probe cards are essential for ensuring quality and reliability in the semiconductor industry.
Technical Bulletin 1128A Mechanical Insulation In Typical Refrigeration Appli...Dyplast Products
The document discusses key considerations for selecting insulation materials for refrigeration applications. It states that thermal conductivity (k-factor) and water vapor transmission (WVT) are the most important properties to consider, as they significantly impact energy costs and system performance over the life of the insulation. Polyisocyanurate insulation has the best combination of k-factor and WVT compared to other common insulants like extruded polystyrene and fiberglass. While capital costs are a factor, prioritizing k-factor and WVT will reduce operating costs and risks of failure in the long run.
Nowadays, mobile consumer electronics devices integrate various wireless interfaces like WIFI, Bluetooth, GPRS and GPS. Various approaches exist to protect the wireless interfaces against ESD stress. In recent years, researchers have focused on so‐called 'co‐design' techniques to solve both functional and protection constraints together which requires both RF and ESD design skills. However many IC designers still prefer to work with 'plug‐n‐play' protection concepts where the ESD clamps exhibit low parasitic capacitance, low series resistance and low leakage. This paper presents measurement results of 3 different SCR based protection approaches that exhibit high Q‐factor and low and stable parasitic capacitance over a broad voltage and frequency range. The clamps are used for protection of LNA circuits in 90nm and 40nm Low Power (LP) CMOS technologies.
IRJET- Geometrical Optimization of Fins for Effective Heat Transfer using CFD...IRJET Journal
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Assessment and Planning in Educational technology.pptxKavitha Krishnan
In an education system, it is understood that assessment is only for the students, but on the other hand, the Assessment of teachers is also an important aspect of the education system that ensures teachers are providing high-quality instruction to students. The assessment process can be used to provide feedback and support for professional development, to inform decisions about teacher retention or promotion, or to evaluate teacher effectiveness for accountability purposes.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
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Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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2. TABLE OF CONTENTS
1. INTRODUCTION
2. PACKAGE DESIGN CONSIDERATIONS
Number of terminals
Electrical design considerations
Thermal design consideration
Reliability
Testability
3. PACKAGE TYPES
Through hole packages
Surface mounted packages
Flip chip packages
Chip size packages
Multi chip modules
3-D VLSI packaging
3. INTRODUCTION
Packaging of electronic circuits is the science and the art of establishing
interconnections and a suitableoperating environment for predominantly electrical
circuits. It supplies the chips with wires to distributesignals and power, removes the
heat generated by the circuits, and provides them with physical supportand
environmental protection. It plays an important role in determining the performance,
cost, andreliability of the system. With the decrease in feature size and increase in
the scale of integration, thedelay in on-chip circuitry is now smaller than that
introduced by the package. Thus, the ideal packagewould be one that is compact,
and should supply the chips with a required number of signal and
powerconnections, which have minute capacitance, inductance, and resistance.
The package should remove theheat generated by the circuits. Its thermal
properties should match well with semiconductor chips toavoid stress-induced
cracks and failures. The package should be reliable, and it should cost much
lessthan the chips it carries
ELECTRONIC PACKAGING REQUIREMENTS
4. PACKAGE DESIGN
CONSIDERATIONS: PACKAGE
PARAMETERS
A successful package design will satisfy all given application requirements at an
acceptable design,manufacturing, and operating expense.
As a rule, application requirements prescribe the number oflogic circuits and/or bits
of storage that must be packaged, interconnected, supplied with electric
power,kept within a proper temperature range, mechanically supported, and
protected against the environment.
Thus, IC packages are designed to accomplish the following three basic functions:
• Enclose the chip within a protective envelope to protect it from the external
environment
• Provide electrical connection from chip to circuit board
• Dissipate heat generated by the chip by establishing a thermal path from a
semiconductor junctionto the external environment
To execute these functions, package designers start with a fundamental concept
and, using principlesof engineering, material science, and processing technology,
create a design that encompasses:
1. Low lead capacitance and inductance
2. Safe stress levels
3. Material compatibility
4. Low thermal resistance
5. Seal integrity
6. High reliability
7. Ease of manufacture
8. Low cost
Success in performing the functions outlined depends on the package design
configuration, the choiceof encapsulating materials, and the operating conditions.
Package design is driven by performance,cost, reliability, and manufacturing
considerations. Conflicts between these multiple criteria are common.The design
5. process involves many trade-off analyses and the optimization of conflicting
requirements.
While designing the package for an application, the following parameters are
considered:
Number of Terminals
The total number of terminals at packaging interfaces is a major cost factor. Signal
interconnections andterminals constitute the majority of conducting elements. Other
conductors supply power and provideground or other reference voltages.The
number of terminals supporting a group of circuits is strongly dependent on the
function of thisgroup. The smallest pin-out can be obtained with memory ICs
because the stream of data can be limitedto a single bit. Exactly the opposite is the
case with groups of logic circuits which result from a randompartitioning of a
computer. The pin-out requirement is one of the key driving parameters for all levels
ofpackaging: chips, chip carriers, cards, modules, cables, and cable connectors.
Electrical Design Considerations
Electrical performance at the IC package level is of great importance for
microwave designs and hasgained considerable attention recently for silicon digital
devices due to ever-increasing speed of today’scircuits and their potentially
reduced noise margins.As a signal propagates through the package, it isdegraded
due to reflections and line resistance. Controlling the resistance and the inductance
associatedwith the power and ground distribution paths to combat ground bounce
and the simultaneous switchingnoise has now become essential. Controlling the
impedance environment of the signal distribution pathin the package to mitigate
the reflection-related noise is becoming important. Reflections, in addition,cause an
increase in the transition time, and may split the signal into two or more pulses with
the potentialof causing erroneous switching in the subsequent circuit and thus
malfunction of the system. Controllingthe capacitive coupling between signal traces
in the signal distribution path to reduce crosstalk is gainingimportance. Increased
speed of the devices demands that package bandwidth be increased to
reduceundue distortion of the signal. All these criteria are related through geometric
variables, such as conductorcross-section and length, dielectric thickness, and the
dielectric constant of the packaging body. Theseproblems are usually handled with
transmission line theory.
6. Thermal Design Considerations
The thermal design objective is to keep the operating junction temperature of a
silicon chip low enoughto prevent triggering the temperature-activated failure
mechanisms. Thus, the package should provide agood medium for heat transfer
from junction to the ambient/heat sink. It is generally recommended tokeep the
junction temperature below 150°C to ensure proper electrical performance and to
contain thepropensity to fail.Thermal expansion caused by heating up the
packaging structure is not uniform — it varies inaccordance with the temperature
gradient at any point in time and with the mismatches in the thermalcoefficient of
expansion. Mechanical stresses result from these differences and are one of the
contributorsto the finite lifetime and the failure rate of any packaging structure.In a
simplistic heat transfer model of a packaged chip, the heat is transferred from the
chip to thesurface of the package by conduction and from the package surface to
the ambient by convection andradiation.Typically, the temperature difference
between the case and ambient is small, and henceradiation can be neglected. This
model also neglects conduction heat transfer out of the package terminals,which
can become significant. A multilayer example, which models the heat transfer from
a region inthe silicon device to the ambient, is shown in Fig. 2.
Figure 1: Steady-state heat flow and thermal resistance in a multilayer structure (a) path of heat flow;
(b)
7. The total thermal resistance from the junctionto the ambient is given by:
The resulting junction temperature, assuming a power dissipation of Pd, is
in analogy with electric circuits. If there are parallel paths for heat flow, the thermal
resistances arecombined in exactly the same manner as electrical resistors in
parallel.
Rθcs, the conductive thermal resistance, is mainly a function of package materials
and geometry. Withthe higher power requirements, one must consider the
temperature dependence of materials selected indesign.
Tj depends on package geometry, package orientation in the application, and the
conditions ofthe ambient in the operating environment. The heat sink is responsible
for getting rid of the heat of theenvironment by convection and radiation. Because
of all the many heat transfer modes occurring in afinned heat sink, the accurate
way to obtain the exact thermal resistance of the heat sink would be tomeasure it.
However, most heat sink manufacturers today provide information about their
extrusionsconcerning the thermal resistance per unit length.
Reliability
The package should have good thermo-mechanical performance for better
reliability. A variety of materialsof widely differing coefficients of thermal expansion
(CTEs) are joined to create interfaces. These interfacesare subject to relatively high
process temperatures and undergo many temperature cycles in theiruseful life as
the device is powered on and off. As a result, residual stresses are created in the
interfaces.These stresses cause reliability problems in the packages.
Testability
Implicit in reliability considerations is the assumption of a flawless product function
after its initialassembly — a zero defect manufacturing. Although feasible in
principle, it is rarely practiced because ofthe high costs and possible loss of
competitive edge due to conservative dimensions, tolerances, materials,and
process choices. So, several tests are employed to assess the reliability of the
packages.
8. PACKAGE TYPES
IC packages have been developed over time to meet the requirements of high
speed and density. Thehistory of IC package development has been the continuous
battle to miniaturize.Figure 3 illustratesthe size and weight reduction of IC packages
over time.
Figure 2: Packaging trends
Figure 3: A generic schematic diagram showing the difference between the surface-mount technology
(upper) and through hole technology
9. Several packages can be classified as follows:
Through Hole Packages
Through-the-board hole mounting technology uses precision holes drilled through
the board and platedwith copper. This copper plating forms the connections
between separate layers. These layers consist ofthin copper sheets stacked together
and insulated by epoxy fiber-glass. There are no dedicated via structuresto make
connections between wiring levels; through holes serve that purpose. Through holes
form asturdy support for the chip carrier and resist thermal and mechanical stresses
caused by the variationsin the expansions of components at raised temperatures.
Different types (Fig. 5) of through holepackages can be further classified as:
Figure 4: Different through mount packages.
Dual-in-Line Packages (DIPs)
A dual-in-line package is a rectangular package with two rows of pins in its two
sides. Here, first the dieis bonded on the lead frame and in the next step, chip I/O
and power/ground pads are wire-bonded tothe lead frame, and the package is
molded in plastic. DIPs are the workhorse of the high-volume andgeneral-purpose
logic products.
Quad Flat Packages (QFPs)
With the advances in VLSI technology, the lower available pin counts of the
rectangular DIP became alimiting factor. With pins spaced 2.4 mm apart on only
two sides of the package, the physical size of theDIP has become too great. On the
other hand, the physical size of an unpackaged microelectronic circuit(bare die)
has been reduced to a few millimeters. As a result, the DIP package has become up
to 50 timeslarger than the bare die size itself, thus defeating the objective of shrinking
the size of the integratedcircuits. So, one solution is to provide pins all around. In
QFPs, pins are provided on all four sides. ThinQFPs are developed to reduce the
weight of the package.
10. Pin Grid Arrays (PGA)
A pin grid array has leads on its entire bottom surface rather than only at its
periphery. This way it can offera much larger pin count. It has cavity-up and cavity-
down versions. In a cavity-down version, a die is mountedon the same side as the
pins facing toward the PC board, and a heat sink can be mounted on its backside
toimprove the heat flow. When the cavity and the pins are on the same side, the
total number of pins is reducedbecause the area occupied by the cavity is not
available for brazed pins. The mounting and wire bonding ofthe dice are also more
difficult because of the existence of the pins next to the cavity. High pin count
andlarger power dissipation capability of PGAs make them attractive for different
types of packaging.
Surface-Mounted Packages
Surface mounting solves many of the shortcomings of through-the-board mounting.
In this technology,a chip carrier is soldered to the pads on the surface of a board
without requiring any through holes. Thesmaller component sizes, lack of through
holes, and the possibility of mounting chips on both sides ofthe PC board improve
the board density. This reduces package parasitic capacitances and
inductancesassociated with the package pins and board wiring. Various types of
surface-mount packages are availableon the market and can be divided into the
following categories.
Figure 5: Different surface-mount packages.
Small-Outline Packages (SOPs)
11. The small-outline package has gull-wing shaped leads. It requires less pin spacing
than through-holemountedDIPs and PGAs. SOP packages usually have small lead
counts and are used for discrete, analog,and SSI/MSI logic parts.
Plastic-leaded Chip Carriers (PLCCs)
Plastic-leaded chip carriers, such as gull-wing and J-leaded chip carriers, offer higher
pin counts thanSOP. J-leaded chip carriers pack denser and are more suitable for
automation than gull-wing leadedcarriers because their leads do not extend
beyond the package.
Leadless Ceramic Chip Carriers (LCCCs)
Leadless ceramic chip carriers take advantage of multilayer ceramic technology.
The conductors are leftexposed around the package periphery to provide contacts
for surface mounting. Dice in leadless chipcarriers are mounted in cavity-down
position, and the back side of the chip faces away from the board,providing a good
heat removal path. The ceramic substrate also has a high thermal conductivity.
LCCCsare hermetically sealed.
Flip-Chip Packages
The length of the electrical connections between the chip and the substrate can be
minimized by placingsolder bumps on the dice, flipping the chips over, aligning
them with the contacts pads on the substrate,and reflowing the solder balls in a
furnace to establish the bonding between the chips and the package.
This method provides electrical connections with minute parasitic inductance and
capacitance. In addition,contact pads are distributed over the entire chip surface.
This saves silicon area, increases themaximum I/O and power/ground terminals
available with a given die size, and provides more efficientlyrouted signal and
power/ground interconnections on the chips.
Figure 6: Flip chip packaging and its interconnections.
12. Chip Size Packages (CSPs)
To combine the advantages of both packaged chip and bare chip in one solution,
a variety of CSPs havebeen developed. CSPs can be divided into two categories:
the fan-in type and the fan-out type.
Fan-in type CSPs are suitable for memory applications that have relatively low pin
counts. This typeis further divided into two types, depending on the location of
bonding pads on the chip surface; theseare the center pad type and the peripheral
pad type. This type of CSP keeps all the solder bumps withinthe chip area by
arranging bumps in area array format on the chip surface.
The fan-out CSPs are used mainly for logic applications: because of the die size to
pin count ratio,the solder bumps cannot be designed within the chip area.
Multi-Chip Modules (MCMs)
In a multi-chip module, several chips are supported on a single package. Most multi-
chip packages aremade of ceramic. By eliminating one level of packaging, the
inductance and capacitance of the electricalconnections among the dice are
reduced. Usually, the dice are mounted on a multilayer ceramic substratevia solder
bumps, and the ceramic substrate offers a dense interconnection network. There
are several advantages of multi-chip modules over single-chip carriers. The multi-
chip moduleminimizes the chip-to-chip spacing and reduces the inductive and
capacitive discontinuities between thechips mounted on the substrate by replacing
the die-bump-interconnect-bump-die path. In addition,narrower and shorter wires
on the ceramic substrate have much less capacitance and inductance thanthe PC
board interconnections.
13. Figure 7: A generic schematic diagram of an MCM, showing how bare dice are interconnected to an
MCM
3-D VLSI Packaging
The driving forces behind the development of three-dimensional packaging
technology are similar to themulti-chip module technology, although the
requirements for the 3-D technology are more aggressive.These requirements
include the need for significant size and weight reductions, higher
performance,small delay, higher reliability, and potentially reduced power
consumption.