SPIE Optoelectronic Integrated Circuits 2011 HelioVolt Presentation

January 27, 2011Thin Film CIGS Photovoltaic Modules:Monolithic Integration and AdvancedPackagingfor High Performance, High Reliability and LowCostLouay EldadaChief Technology Officer © 2011 HelioVolt Corporation 1

Next Generation High-Performanceand Low-Cost Solar Technology• Disruptive CIGS PV technology: high efficiency low cost monolithic modules• Extensive CIGS intellectual property portfolio• 9+ years and ~$145MM of R&D• Unique technology commercialization partnership with NREL• Fully equipped production line and R&D line in Austin• Team with deep technical expertise• NREL-confirmed ~12% (11.8±0.6%) efficiency champion production module, with 10.8% average efficiency• Efficiency roadmap to 16%+ in 2014• Plan for production expansion under development© 2011 HelioVolt 2 Corporation

Competitive Technology Advantage process advantages • FASST® CIGS Glass In – Two-stage process provides maximum flexibility to optimize precursor deposition method and composition of each layer: higher efficiency – Most rapid synthesis of CIGS from precursors of any method: Glass reduces capital costs Preparation – Demonstrated state of the art crystalline quality: higher efficiencyFASST® CIGS Process – Unique, rapid, flexible optimization of CIGS surface quality: higher Module efficiency Formation • Advanced NREL liquid precursor technology Final Assembly – Reduces capital costs and COGS & Test • Monolithic module circuit integration – Reduces module assembly costs compared to discrete cell assembly • Advanced module packagingModule Out – Unique, high performance encapsulant, edge sealant, and potting compound supports product lifetime beyond standard 25 year warranty: reduces cost of electricity (¢/kWh) © 2011 HelioVolt 3 Corporation

CIGS: Highest Thin FilmEfficiency Mono-Crystalline Si Multi-Crystalline Si CIGS CdTe a-Si/Micro a-Si 1-j 0% 5% 10% 15% 20% 25% 2010 Module Efficiency Record Cell Efficiency Source: Greentech Media, Prometheus Institute and Wall Street research.© 2011 HelioVolt 4 Corporation

CIGS Contenders Approach Process Company Substrate Cell or Module Technology Co-evaporation Glass Module Co-evaporation Glass Tubular “Module” Selenization Glass Module Sputtering Steel Foil Cell Nanoparticle Metal Foil Cell Sintering Electroplating Steel Foil Cell HelioVolt FASST® Currently Glass Module© 2011 HelioVolt 5 Corporation

CIGS Contenders Results CIGS Deposition Typical Module Company COGS CapEx Uniformity Efficiency High High High 10-12% Moderate High High 9% Moderate Moderate High 10-12% Low Moderate High 10% Low Moderate Moderate 9% Low Moderate Moderate 9% High Low Low 10-12%© 2011 HelioVolt 6 Corporation

Monolithic Integration is Key to CostLeadership and Product Reliability HelioVolt Process Competitors’ CIGS Cell-Based Processes Glass Glass In In Additional Costs Stainless steel foil $0.08 Glass Substrate $0.06 $0.06 Preparation Preparation Higher non-material FASST® CIGS CIGS ? $0.07 $0.15 inputs (e.g. labor) Process Process Module Contact & Grid $0.01 $0.01 Higher yield loss ? Formation Formation Final Assembly $0.13 ? Cell Cut & Sort Stringing material $0.12 & Test Total: $0.27/Wp Cell Stringing $0.12 Two encapsulant $0.04 layers and outer frame Final Assembly $0.17 Add’l: Module & Test Out $0.24+/Wp Total: $0.51+/Wp Module Out Note: Input materials cost / Wp in cents.© 2011 HelioVolt 7 Corporation

HelioVolt PV Module Production Line Moly Deposition Exit Precursor Deposition Load FASST® Processor LoadFASST® Processor Unload Buffer Load Final PVIC Pattern Step PVIC Lamination Junction Box Attach Final Eff. Test © 2011 HelioVolt 8 Corporation

FASST® Reactive Transfer Process Non-Contact Transfer (NCT™) Synthesis Process Step Cu, In, Ga, Se • Independent deposition of distinct Substrate compound precursor layers on substrate and source plate Source Plate with Transfer • Rapid non-contact reaction Film Pressure – Turns stack into CIGS with high efficiency Heat structure – Combines benefits of sequential selenization with Close-Spaced Vapor Transport (CSVT) Source Plate for junction optimization • CIGS adheres to the substrate and the source plate is reused SubstrateCIGSLayer Rapid manufacturing process reduces capital amortization cost © 2011 HelioVolt 9 Corporation

CIGS Material FundamentalsCuInSe2 chalcopyrite crystal structure: T–X section of the phase diagram along the(a) conventional unit cell of height c, with a Cu2Se-In2Se3 pseudobinary section of thesquare base of width a Cu–In–Se chemical system.(b) cation-centered first coordination shell : CuInSe2 chalcopyrite phase(c) anion-centered first coordination shell : In-rich/Cu-poor (Cu2In4Se7 & CuIn3Se5)showing bond lengths dCu–Se and dIn–Se. ordered defect compound (ODC) phase B.J. Stanbery, Critical Reviews in Solid State and Materials Sciences, 27(2):73-117 (2002)© 2011 HelioVolt 10 Corporation

Role of Micro and Nanostructuring in CIGS PV Device Operation Observations on Device-Quality ( >15%) CIGS:  Large columnar grains  Copper deficiency compared to -CuInSe2  Compositions lie in the equilibrium 2-phase domain: domains, Cu-rich with p-type conductivity and domains, Cu-poor with n-type conductivity, form nanoscale p-n junction networks*; n-type networks act as preferential electron pathways, p-type networks act as preferential hole pathways, positive and negative charges travel to the contacts in physically separated paths, reducing recombination *Intra-Absorber Junction (IAJ) model, APL 87, 121904 (2005)© 2011 HelioVolt 11 Corporation

Composition Fluctuations and Carrier Transport in CIGS PV AbsorbersExperimental results* HAADF-TEM & Nanoscale EDS – 5-10 nm characteristic domain size – Chemical composition fluctuations found across the domains p1: Cu:In:Ga:Se=31:14:7:48 p2: Cu:In:Ga:Se=27:15:9:49 p3: Cu:In:Ga:Se=30:15:6:49 – Dark domains are relatively Cu *Applied Physics Letters, 87, 2005, 121904 rich, bright domains are relatively Cu poorHAADF-TEM: High-Angle Annular Dark-Field Transmission Electron MicroscopyEDS: Energy-Dispersive X-ray Spectroscopy © 2011 HelioVolt 12 Corporation

Reactive Transfer ProcessingCompound PrecursorDepositionhave been developed for• Two methods deposition of compound precursors• Low-temperature Co-evaporation – Equipment requirements similar to conventional single-stage co-evaporation but lower temperatures lead to higher throughput and reduced thermal budget• Liquid Metal-Organic molecular solutions – Proprietary inks developed under NREL CRADA (Cooperative Research And Development Agreement) – Decomposition of inks leads to formation of inorganic compound precursor films nearly indistinguishable from co-evaporated films (for some compounds)© 2011 HelioVolt 13 Corporation

HelioVolt-NREL CRADATechnology Advantages• Atmospheric (non-vacuum) processes – Low capital equipment cost, 10-20x reduction vs. vacuum equipment – Low thermal budget, low energy consumption – Small footprint, 5-10x reduction vs. vacuum equipment – High uptime – High throughput• Inks – Good compositional control by chemical synthesis – A variety of materials can be synthesized; we have proprietary Cu-, In- and Ga-containing inks that densify to multinary selenide precursors• Efficient use of materials – >95% material utilization vs. 80% for sputtering, 60% for© 2011 HelioVolt evaporation 15 Corporation

Printed Electronics Equipment &ProcessesLeveraged in PV Printed Electronics Conventional ElectronicsSimple Circuitry Complex Circuitry – Slow or static circuits – Fast switching circuits – Low integration density – High integration density – Large areas – Small areas – Rigid or flexible substrates – Rigid substrates – Simple fabrication – Complex fabrication – Low fabrication cost – High fabrication cost Low Cost High Cost© 2011 HelioVolt 16 Corporation

Metal-Organic Decomposition(MOD) Precursor Film Deposition• Inorganic compound reaction CIGS synthesis provides pathway for evolutionary adoption of MOD precursors• Key drivers – Low capital equipment cost – Low thermal budget – High throughput• Flexibility – Good compositional control by chemical synthesis – Variety of Cu-, In- and Ga-containing inks can be synthesized and densified to form multinary sulfo-selenide precursors• Efficient use of materials© 2011 HelioVolt 17 Corporation

NREL CRADA – Hybrid CIGS by FASST® XRD • Chalcopyrite CIGS (& Mo) SEM • (220/204) preferred orientation, • Exceptionally large grains helps junction formation and • Columnar structure improves solar cell performance Hybrid CIGS efficiency reached parity with PVD- based CIGS© 2011 HelioVolt 20 Corporation

Cd-Free Buffer for a Cd-Free Product CdS buffer Cd-free buffe Uniform conformal Cd-free buffer on CIGS Quantum Efficiency (QE) of CIGS with Cd- free buffer shows improvement over CdS, especially in the 400-500 nm wavelength range© 2011 HelioVolt 23 Corporation

Sputtered Back Contact (Mo) Pattern 1 (Laser Scribe) Module Fab Process Cu-In-Ga-Se Precursor Films FlowCIGS by FASST Reactive Transfer Buffer Layers Pattern 2 (Mech. Scribe) Sputtered Front Contact (TCO) Pattern 3 (Mech. Scribe) Bus Bars and Tabs PVIC PVIC Test Edge Sealant Application Glass Module Out In Encapsulant Application = 2.5 Lamination hrs Final Test Quality Control © 2011 HelioVolt 25 Corporation

Photovoltaic Integrated Circuit (PVIC) manufacturing steps of monolithic Typical interconnection for CIGS PV modules Cell Length W.N. Shafarman et al., „Cu(InGa)Se2 Solar Cells‟ in Handbook of Photovoltaic Science and Engineering (2003) Scribe Zone TCO Window – – – – – Buffer Cell Width – P3 CIGS Absorber P2 – Back Contact P1 – Substrate Bus Bar Segment Isolation & Interconnection Scribes+ - and Charge Transport © 2011 HelioVolt 26 Corporation

Modeling for Device/Module Design• HelioVolt CIGS device/module design further improved by various modeling methods, e.g. 2-D circuit design, device physics modeling, and thermodynamics modeling Circuit model Segment/Cell Sub-cell network TCO network Module Mo network 80 66 Sub-cell Module Power Output 79 65.5 Module FF (%) 78 65 (W) 77 64.5 76 Power 64 FF (%) 75 63.5 8 10 12 14 16 18 20 22 TCO Sheet Resistance (Ω/□)© 2011 HelioVolt 27 Corporation

Product Scaling and Performance Experience 14% Cell Efficiency 0.66cm2 1364x scale-up Cell 3% 3 Months Prototype Module 12% 30cmx30cm Efficiency Scalability Proof 5% Prototype 8x scale-up 2 Months 12% Efficiency 8% Module 2% Production Module Progress 4 Months 10 Months 1.2mx0.6m Commercial Production Size© 2011 HelioVolt 28 Corporation

FASST® CIGS Production Modules 120x60 cm2 Module Top view with SEM Cross-sectional SEM view Faceted CIGS crystals absorb light Large grains efficiently from all directions from dawnwith no horizontal to dusk, giving HelioVolt CIGS itsgrain boundaries characteristic black color support high efficiency © 2011 HelioVolt 29 Corporation

Production Module Results in Last Year 12 Average Efficiency 11 Continuously Increasing 10 Equipment Upgraded 9 8 fficiency (%)Efficiency 7 (%) 6 5E 4 3 2 1 0 113 127 141 155 169 183 197 106 120 134 148 162 176 190 204 211 218 225 232 239 246 253 260 267 274 281 288 295 302 309 316 323 330 337 344 351 358 365 372 379 386 393 1 8 15 29 43 57 71 85 99 22 36 50 64 78 92 G2 Modules – Feb ’10- G2 Modules – Feb 2010-present present © 2011 HelioVolt 30 Corporation

G2 Module Efficiency Progress 12% Max 120% 11% 110% CV = Std Dev Average 10% 100% Coefficient of Variation (CV) Average Efficiency 9% 90% 8% 80% 7% 70% 6% 60% Equipment 5% 50% C Capability 4% 40% V Upgrade and 3% 30% Characterization 2% 20% 1% 10% 0% 0% MAY JUN JUL AUG SP E OCT NOV 2010 Efficiency: continuous improvement in efficiency average, maximum, and distribution © 2011 HelioVolt 31 Corporation

Best-In-Class Proprietary Packaging • Edge Sealing: HVC has unique edge sealant solution that guarantees 25 year lifetime in high humidity environments • Lamination: HVC has unique encapsulant sheet with high optical transparency, light trapping capability, good chemical compatibility with thin films, and outstanding ability to keep moisture out and withstand UV exposure • Junction box: HVC has a J-box that is proven in the field; includes bypass diode to protect string from partial shading losses • Front glass: HVC uses high-transparency low-iron tempered superstrate glass for highest optical performance and reliability © 2011 HelioVolt 33 Corporation

HelioVolt CIGS Module Product SpecElectrical Performance * HVC-170XMaximum Power – Pmax 68.0 WattsOpen Circuit Voltage – Voc 74.5 VoltsShort Circuit Current – Isc 1.5 AmpsOperating Voltage – Vmp 55.0 VoltsCurrent at Operating Voltage – Imp 1.24 AmpsMaximum System Voltage – UL 600 VoltsMaximum System Voltage – IEC 1000 Volts *Standard Test Conditions (STC). Ratings are +/-10%.Physical & Mechanical HVC-170XSpecificationsLength 1210 mmWidth 601 mmThickness 6.7 mmArea 0.73 m2Weight 12.3 kgPositive Leadwire Length 660 mmNegative Leadwire Length 660 mm HVC-170XConnectors MC-4 • Construction: Glass-glassBypass Diode Yes laminateCell Type CIGS • Certification: IEC 61646, IECFrame None 61730, UL 1703, UL 790 Class ACover Type Tempered Glass fire rating, CEC listing, CE mark Edge in processEncapsulation • Warranty: 25 years Seal/Thermoplastic © 2011 HelioVolt 34 Corporation

Certification Testing Description Test (per UL/IEC requirements) Performance +/- 10% of specified electrical parameters Outdoor 60 kWh/m2, maintain performance ExposureTemperature & RH Environmental Testing Thermal • -40 to +90°C Cycling Damp Heat • 85°C / 85%RH Humidity • -40 to +90°C w/ condensation Freeze Impact Testing Mechanical • Shading hot spot Robustness • Connectors/J-box pull test • Mech loading: 400 lbs, 30 minutes UL 1703: Flat-Plate Photovoltaic Modules ball, Panels • Impact: 2” 1.18 lb steel and 51” drop IEC 61646: Shock Hazard • No leakage current after Thin-film Terrestrial Photovoltaic (PV) Modules environmental exposure – Design Qualification and Type Approval Mechanical Load Testing IEC 61730: PV Module – Safety Qualification UL: Underwriters Laboratories, IEC: International Electrotechnical Commission © 2011 HelioVolt 35 Corporation

Completed Reliability Screening Tests • Completed Damp Heat (DH) and %of Initial Pmax, Light Soak Stabilized DH T est Humidity Freeze (HF) testing for 120% 99.9% 100% 89.9% 87.5% pre-certification reliability % of Initial Pmax 80% screening 60% 40% • DH Test: 20% – Followed IEC protocol 1000 hrs 0% HelioVolt Competitor A Competitor B 85°C, 85% RH (Relative Humidity) Module Manufacturer – Passed with virtually no DH %of Initial Pmax, Light Soak Stabilized degradation HFT and DH+HFT est est • HF Test: 120% 107.1% 98.2% – All modules followed IEC protocol, 100% % of Initial Pmax 80% Double which includes 50 cycles of torture not 60% required in thermal cycling (TC*) pre- 40% certification conditioning, followed by 10 cycles testing 20% of HF** 0% – Half of the modules had HFExposure Only DH + HF Exposure * TC cycle: -40°C to 85°C, 10min dwell at extremes1000 hrs additionally gone through** HF cycle: -40°C to 85°C/85%RH, 30min dwell at -40°C, 20hr dwell at 85°C/85%RH HF DH+HF of IEC DH test – Passed with no degradation: © 2011 HelioVolt 36 Corporation

HelioVolt Module Rooftop Test ArrayFactory Rooftop HelioVolt module test array. Array tracksperformance of HelioVolt, as well as other thin-film and siliconmodules, and inverters © 2011 HelioVolt 37 Corporation

HV Rooftop Test FacilitySTATUS CAPABILITIES• Phase 1 installation complete • Irradiance• ProSolar, Schletter, and CoolPly – Plane of Array (POA) racking – Global Total (GT)• Xantrex, SMA, Fronius Inverters • Weather• Competitor and HelioVolt modules – Temperature• 10kW initial capacity – Relative Humidity• Thorough monitoring of energy • Electrical harvest and weather conditions – DC Voltage – DC Current – AC Voltage – AC Current – Inverter Efficiency © 2011 HelioVolt 38 Corporation

HelioVolt Modules(20° tilt, ballasted, Schletter racking)• 32 HelioVolt modules in 4 strings on Schletter racking• Full light soak effect achieved on first day 39

Rooftop Performance –Comparison of All Arrays One Day Comparison, All Arrays HelioVolt CIGS Tier 1 mc-Si Tier 1 CdTe 2nd Glass Laminate CIG Tubular CIGS• HelioVolt modules have highest yield, followed by Tier 1 mc-Si modules; CdTe & other CIGS lag behind© 2011 HelioVolt 40 Corporation

Roadmap to 16% ModuleEfficiency 18% 12% Advanced TCO, Enhanced Transmission, Ultrafast Heating, Light Trapping Active Predictive Design Quenching, 6% Advanced Baseline Process Composition Grading Control 0% 2010 2011 2012 2013 • Development work based on HelioVolt patents and trade secrets will drive module efficiency from 10% to 16% • Applied Research – HelioVolt‟s partnership with NREL will drive module efficiency from 16% to 21%© 2011 HelioVolt 41 Corporation

Product Portfolio Built on Standard Component PlatformCommercial Rooftop Utility ScaleSystemsBIPV – Sunshades BIPV – Spandrels Parking Structures 5‟X5‟ 1‟X1‟ 3 0 0 m m CIGS P VIC 2‟X4‟ • Front view • 5‟x5‟ Element • Framing provided by curtain wall manufacturer • Standard or custom element © 2011 HelioVolt 42 Corporation

Product Portfolio Evolution 2011 2012 2013 2014 Standard modules for commercial rooftops and utility applications. Standard modules offered with system level solutions for commercial rooftops (including mounting, power management). New standard component introduced to reduce balance of systems costs. Standard modules adapted for BIPV applications (facades, sunshades, roof tiles) including BIPV components with integrated power management.Efficiency 11% 12% 14% 16% © 2011 HelioVolt 43 Corporation

Acknowledgments• Dr. Keith Emery and his team for the module efficiency verification testing National Renewable Energy Laboratory• Prof. James Sites and his team for the help with cell characterization Colorado State University• Dr. David S. Ginley and his team for the CRADA work on ink development National Renewable Energy Laboratory• The entire HelioVolt team for their role in the successful scale up of the CIGS reactive transfer technology HelioVolt Corporation 44

http://www.heliovolt.net	223
http://www.heliovolt.com	185
http://heliovolt.net	23
http://heliovolt.com	4
http://twitter.com	1

SPIE Optoelectronic Integrated Circuits 2011 HelioVolt Presentation

by HelioVolt on Jan 28, 2011

Accessibility

Categories

Upload Details

Usage Rights

5 Embeds 436

Statistics

SPIE Optoelectronic Integrated Circuits 2011 HelioVolt Presentation Presentation Transcript