This document summarizes the double-gate MOSFET transistor. It begins by describing the basic operation of a single-gate MOSFET and then discusses the scaling limitations of bulk MOSFETs, such as decreasing carrier mobility and threshold voltage rolloff as channel length decreases. It introduces the double-gate MOSFET as a way to better control the channel and reduce short-channel effects. Key features of the double-gate MOSFET include two gates that control the ultra-thin body channel and allow direct scaling to small channel lengths of 20nm or less. Fabricating double-gate MOSFETs using a silicon-on-insulator approach provides benefits like low leakage currents. The double gates provide improved performance
Here are the all short channel effects that you require.It consist of:-
Drain Induced Barrier Lowering
Hot electron Effect
Impact Ionization
Surface Scattering
Velocity saturation
Reduced channel length cause departures from long channel behaviour as two-dimensional potential distribution and high electric fields give birth to Short channel effects.
SHORT-CHANNEL EFFECTS
A MOSFET is considered to be short when the channel length ‘L’ is the same order of magnitude as the depletion-layer widths (xdD, xdS). The potential distribution in the channel now depends upon both, transverse field Ex, due to gate bias and also on the longitudinal field Ey, due to drain bias When the Gate channel length <<1 m, short channel effect becomes important .
This leads to many
undesirable effects in MOSFET.
The short-channel effects are attributed to two physical phenomena:
A) The limitation imposed on electron drift characteristics in the channel,
B) The modification of the threshold voltage due to the shortening channel length.
In particular five different short-channel effects can be distinguished:
1. Drain-induced barrier lowering and “Punch through”
2. Surface scattering
3. Velocity saturation
4. Impact ionization
5. Hot electrons
Here are the all short channel effects that you require.It consist of:-
Drain Induced Barrier Lowering
Hot electron Effect
Impact Ionization
Surface Scattering
Velocity saturation
Reduced channel length cause departures from long channel behaviour as two-dimensional potential distribution and high electric fields give birth to Short channel effects.
SHORT-CHANNEL EFFECTS
A MOSFET is considered to be short when the channel length ‘L’ is the same order of magnitude as the depletion-layer widths (xdD, xdS). The potential distribution in the channel now depends upon both, transverse field Ex, due to gate bias and also on the longitudinal field Ey, due to drain bias When the Gate channel length <<1 m, short channel effect becomes important .
This leads to many
undesirable effects in MOSFET.
The short-channel effects are attributed to two physical phenomena:
A) The limitation imposed on electron drift characteristics in the channel,
B) The modification of the threshold voltage due to the shortening channel length.
In particular five different short-channel effects can be distinguished:
1. Drain-induced barrier lowering and “Punch through”
2. Surface scattering
3. Velocity saturation
4. Impact ionization
5. Hot electrons
In MOS, source-drain regions of adjacent MOS transistors together with interconnection metal lines may constitute parasitic MOS transistors unless they are isolated from each other. Hence, each MOSFET must be electrically isolated from each other. Device Isolation Techniques in VLSI microfabrication of MOS are discussed.
In MOS, source-drain regions of adjacent MOS transistors together with interconnection metal lines may constitute parasitic MOS transistors unless they are isolated from each other. Hence, each MOSFET must be electrically isolated from each other. Device Isolation Techniques in VLSI microfabrication of MOS are discussed.
Multiple patterning is a class of technologies for manufacturing integrated circuits (ICs), developed for photolithography to enhance the feature density. The simplest case of multiple patterning is double patterning, where a conventional lithography process is enhanced to produce double the expected number of features. The resolution of a photoresist pattern is believed to blur at around 45 nm half-pitch. For the semiconductor industry, therefore, double patterning was introduced for the 32 nm half-pitch node and below. This presentation gives us an insight of why multiple patterning is an important to give us a better resolution below 32nm.
Ultra-thin body SOI MOSFETs: Term Paper_class presentation on Advanced topics...prajon
This slide describes one of the technology n the field of semiconductor devices, Ultra thin body SOI (Silicon on Insulator) MOSFETs and its various uses and characteristics.
Analysis Of 3C-Sic Double Implanted MOSFET With Gaussian Profile Doping In Th...IJRES Journal
The present work aims at the design of 3C-SiC Double Implanted Metal Oxide Semiconductor Field Effect Transistor (DIMOSFET) with Gaussian doping profile in drift region for high breakdown voltages. By varying the device height ‘h’, function constant m and peak concentration 𝑁0, analysis has been done for an optimum profile for high breakdown voltage. With Gaussian profile peak concentration 𝑁0 = 1016 𝑐𝑚−3 at drain end and m as 1.496 ×10−2cm, highest breakdown voltage of 6.84kV has been estimated with device height of 200μm.
Microelectronic technology
This report briefly discusses the need for Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs), their structure and principle of operation. Then it details the fabrication and characterization of the MOSFETs fabricated at the microelectronic lab at University of Malaya
shows the simulation and analysis of a MOSFET device using the MOSFet tool. Several powerful analytic features of this tool are demonstrated, including the following:
calculation of Id-Vg curves
potential contour plots along the device at equilibrium and at the final applied bias
electron density contour plots along the device at equilibrium and at the final applied bias
spatial doping profile along the device
1D spatial potential profile along the device
Structural and Electrical Analysis of Various MOSFET DesignsIJERA Editor
Invention of Transistor is the foundation of electronics industry. Metal Oxide Semiconductor Field Effect Transistor (MOSFET) has been the key to the development of nano electronics technology. This paper offers a brief review of some of the most popular MOSFET structure designs. The scaling down of planar bulk MOSFET proposed by the Moore’s Law has been saturated due to short channel effects and DIBL. Due to this alternative approaches has been considered to overcome the problems at lower node technology. SOI and FinFET technologies are promising candidates in this area.
Dual Metal Gate and Conventional MOSFET at Sub nm for Analog ApplicationVLSICS Design
The use of nanometer CMOS technologies (below 90nm) however brings along significant challenges for circuit design (both analog and digital). By reducing the dimensions of transistors many physical phenomenon like gate leakage, drain induced barrier lowering and many more effects comes into picture. Reducing the feature size in the technology of device with the addition of ever more interconnect layers, the density of the digital as well as analog circuit will increase while intrinsic gate switching delay is reduced . We have simulated conventional and DMG MOSFET at 30nm scale using Silvaco TAD tool and obtained result. A two dimensional device simulation was carried out and observed that DMG MOSFET has a low leakage current as compared to conventional MOSFET and find suitable application in analog circuits.
A Study On Double Gate Field Effect Transistor For Area And Cost Efficiencypaperpublications3
Abstract: Proposal for a field effect transistor had been presented, with numerical device simulations to verify the title in every manner possible. The two transitional field effect transistors like pMOS and nMOS functions are simultaneously performed, working as one or as the other according to the voltage applied to the gate terminal. Increase in the circuit speed is observed when this technology is implemented on the device suggested with respect to the standard CMOS technology, presented a drastic reduction of number devices and associated parasitic capacitances. In addition to it IC obtained with the proposed device are fully compatible with the standard CMOS technology and the fabrication processes. Fabrication of Static Ram cells with three transistors only with minimum dimensions and a single bit line by saving silicon area and increasing the memory performance with respect to standard CMOS technologies. It is also presented that the fully compatible CMOS process can be used to successfully manufacture the new FET structure.
ULTRA HIGH SPEED FACTORIAL DESIGN IN SUB-NANOMETER TECHNOLOGYcscpconf
This work proposes a high speed and low power factorial design in 22nm technology and also it counts the effect of sub nano-meter constraints on this circuit. A comparative study for this
design has been done for 90nm, 45nm and 22nm technology. The rise in circuit complexity and speed is accompanied by the scaling of MOSFET’s. The transistor saturation current Idsat is an important parameter because the transistor current determines the time needed to charge and discharge the capacitive loads on chip, and thus impacts the product speed more than any other transistor parameter. The efficient implementation of a factorial number is carried out by using
a decremented and multipliers which has been lucidly discussed in this paper. Normally in a factorial module a number is calculated as the iterative multiplication of the given number to
the decremented value of the given number. A Parallel adder based decremented has been proposed for calculating the factorial of any number that also includes 0 and 1. The
performances are calculated by using the existing 90-nm CMOS technology and scaling down the existing technology to 45-nm and 22-nm.
A NOVEL POWER REDUCTION TECHNIQUE FOR DUAL-THRESHOLD DOMINO LOGIC IN SUB-65NM...VLSICS Design
A novel technique for dual- threshold is proposed and examined with inputs and clock signals combinationin 65nm dual- threshold footerless domino circuit for reduced leakage current. In this technique a p-type and an n-type leakage controlled transistor (LCTs) are introduced between the pull-up and pull-down network and the gate of one is controlled by the source of the other. A high-threshold transistor is used in the input for reducing gate oxide leakage current which becomes dominant in nanometer technology. Simulations based on 65nm BISM4 model for proposed domino circuits shows that CLIL (clock low and input low) and CHIH (clock high and input high) state is ineffective for lowering leakage current. The CLIH (clock low input high) state is only effective to suppress the leakage at low and high temperatures for
wide fan-in domino circuits but for AND gate CHIL (clock high input low) state is preferred to reduce the leakage current. The proposed circuit technique for AND2, OR2, OR4 and OR8 circuits reduces the active power consumption by 39.6% to 57.9% and by 32.4% to 40.3% at low and high die temperatures respectively when compared to the standard dual-threshold voltage domino logic circuits.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
4. MOSFET OPERATION
Step 1: Apply Gate Voltage
SiO2 Insulator (Glass)
Gate
Source
Drain
5 volts
holes
N
N
electrons
P
electrons to be
transmitted
Step 2: Excess electrons surface
in channel, holes are repelled.
Step 3: Channel becomes
saturated with electrons.
Electrons in source are able to
flow across channel to Drain.
5. Scaling limits of BULK MOSFET
Limit
for supply voltage (<0.6V)
Limit
for further scaling of tox (<2nm)
Minimum
Discrete
channel length Lg=50nm
dopant fluctuations
Dramatic
short-channels effects (SCE)
6. Problem 1: Carrier Mobility Decreases as Channel
length decrease and Vertical Electric fields increase
Problem 2: VT Rolloff as Channel length decreases
Problem 3: Tunneling Through Gate Oxide (off state
current)
Problem 4: Wattage/Area increases as density increases
7. How can we follow Moore’s law ?
By moving to DG MOSFETs
DG might be the unique viable alternative to build nano
MOSFETs when Lg<50nm
Because:
- Better control of the channel from the gates
- Reduced short-channel effects
- Better Ion/Ioff
- Improved sub-threshold slope (60mV/decade)
- No discrete dopant fluctuations
8. Double Gate MOSFET
Features:
• Upper and lower gates control the channel region
• Ultra-thin body acts as a rectangular quantum well at device limits
• Directly scalable down to 20 nm channel length
9. Silicon-on-Insulator (SOI) Approach
Silicon channel layer grown on a layer
of oxide.
Absence of junction capacitance makes
this an attractive option.
Low leakage currents and compatible
fabrication technology.
10. Silicon-on-Insulator (SOI) Approach
Silicon channel layer grown on a layer
of oxide.
Absence of junction capacitance makes
this an attractive option.
Low leakage currents and compatible
fabrication technology.
11.
12. To reduce SCE’s,
aggressively
reduce Si layer
thickness
E-Field lines
G
S
BOX
Double gates
electrically shield
the channel
G
D
S
BOX
D
G
Double-Gate
Regular SOI MOSFET Double-gate MOSFET
Single-Gate SOI
13. Gate
n+ poly gate
Gate
Vdd
n+ source
n+ drain
Vdd
n+
source
n+
drain
p substrate
Gate
• Single Gate to Double Gates
–Better short-channel effect control
–More Scalable
14. •
•
•
•
Higher current drive
better performance
Prophesized to show higher tolerance to scaling.
Better integration feasibility, raised source-drain structure, ease in integration.
Larger number of parameters to tailor device performance
15. Layout
• Type I : Planar Double Gate
• Type II: Vertical Double Gate
• Type III: Horizontal Double Gate (FinFET)
16. Reduced Channel and Gate Leakage
• Short channel effects are seen in Standard silicon MOS devices
• DGFET offers greater control of the channel because of the double gate
• Gate leakage current is prevented by a thick gate oxide
17. Threshold Voltage Control
Silicon MOS Transistor:
• Increased body doping used to control VT for short channel
• Small number of dopant atoms for very short channel
• Lowest VT achievable is .5V
Double Gate FET :
• Increased body doping
• Asymmetric gate work functions (n+ / p+ gates)
• Metal gate
• VT of .1V achievable through work function engineering
18. Increased Carrier Mobility
Silicon MOS Transistor:
• Carrier scattering from increased body doping
• Transverse electric fields from the source and drain reduce mobility
Double Gate FET:
• Lightly doped channel in a DGFET results in a negligible depletion charge
• Asymmetric gate: experiences some transverse electric fields
• Metal gate: transverse electric field negligible with increased channel control
19. Reduced Power Consumption
• Double Gate coupling allows for higher drive currents at lower supply
voltage and threshold voltage
• Energy is a quadratic function of supply voltage
• Reduced channel and gate leakage currents in off state translate to huge
power savings
• Separate control of each gate allows dynamic control of VT :
Simplified logic gates would save power and chip area
20. Challenges Facing Double Gate Technology
1) Identically sized gates
2) Self-alignment of source and drain to both gates
3) Alignment of both gates to each other
4) Connecting two gates with a low-resistance path
21. Ultimate Double Gate Limits
1) Thermionic emission above the channel potential barrier:
Short channel effects lower potential barrier
2) Band-to-band tunneling between body and drain pn junction:
Body-drain electric field increases tunneling probability
3) Quantum mechanical tunneling directly between source and drain:
Extremely small channel lengths correspond to narrow
potential barrier width
4) Other effects of quantum confinement in the thin body
22. Front Gate
• Short channel effect control
– Better scalability
– Lower sub threshold
current
• Higher On Current
• Near-Ideal Sub threshold
slope
• Lower Gate Leakage
• Elimination of Vt variation
due to Random dopant
fluctuation
Gate
(metal/poly)
Source
n+
source
body
Drain
n+
drain
Gate
(metal/poly)
Back Gate
DG devices are very
promising for circuit
design in sub-50nm
technology
