Advanced wafer processing: Ready for the new PV generation 5 th Annual c-si PVMC Workshop Christoph Eggimann

Transcription

1 Advanced wafer processing: Ready for the new PV generation 5 th Annual c-si PVMC Workshop Christoph Eggimann

2 The new PV generation A B Diamond wire Thinner wafer Lower costs Single wafer tracking Quality & performance control Heterojunction (HJT) Texture a-si front/rear side TCO / metal rear contact Print front side Test & sort C Curing High efficiency Lower system cost (BOS) Independent of wafer thickness Only 6 process steps Low CoO Temperature coefficient Higher energy yield Bifacial Higher energy yield D E Adapted test metrology High cap cells Busbarless cells DragonBack PED (chipping) SmartWire Connection (SWCT) TCO layer and wafer thickness suitable for SmartWire 80% less silver Higher energy yield Higher efficiency Longevity and micro-crack resistant D B A C E 2 Meyer Burger /

3 Enabling wafer technologies Bricking Technology Slicing Technology Diamond Wire Wafer Inspection 3

4 Bricking Technology: Integration and Automation for minimized production cost Material-efficiency 0.42mm kerf silicon savings Manpower-efficiency 1 man operation fully automated 4 Process-efficiency diamond wire / water only / glue free Space-efficiency 50% less space for equipment and buffers

5 Performance PV wafering evolution Newest Generation Diamond Wire Saw Slurry Saws DW Upgrades Dedicated DW Saws Diamond Wire Management System (DWMS) Kerf µm <90 Time hrs DW Use m/wf Capacity MW Based on Mono 156 x 156 x 0.18 mm Wafers

6 500 MW fab yesterday and today 6 Conventional Slurry Wire Saws Latest Generation Diamond Wire Saws

7 Wire Consumption Matters Glue Electricity Spare parts Beam WGR Cutting fluid Depreciation Operator Wire Challenge DW Wafering Cost of Ownership: Diamond Wire consumption is the biggest cost driver (approx. 50%) Diamond wire consumption is influenced by wire wear: 1. CWW = wear from cutting 2. NCWW = wear from winding Wafering Cost of Ownership 7

8 How to improve wire performance Conventional Wire Management Diamond Wire Management System (DWMS) Working (Winder) Area Storage (Supply) Area 8

9 How does DWMS work? 9

10 What is the Impact of Thinner Wires? 80 µm wire 70 µm wire 60 µm wire 100 µm 90 µm 80 µm 10 µm less silicon > USD/yr Savings per machine Challenge: How to capture this cost saving potential? 10 check base data

11 Thin wires require improved tension control Wire Tension Decoupling Low Inertia Pulleys Tight Wire Tension Control Dedicated Wire Development ± 0.5 N 11

12 Tension Enablers of thin wire slicing Limit Tight wire tension control Diamond Wire Management System Conventional Technology DWMS Technology Enables thin wire slicing

13 TTV Line (um) High performing wire with consistent quality enables higher yields Meyer Burger Diamond Wire Coordinated wire, equipment and process development premium performance Manufacturing controls, detection algorithms, automatic feedback loops improved quality Sample TTV Data Mono 156 / 70 um wire / 1 m/wf / <2 hr cut time Spool 1 Spool 2 Cut Nr 13

14 Saw Yield (%) Cut Time (hrs) Wire Consumption (m/wf) Mono DW Sample Process Wire usage Cut time Fast cut Mono fast cut sample results 70 µm wire 2.5 Low wire usage* m/wf hrs Saw Yield Cut time Wire consumption Cut Nr Mono 156 *) process in development

15 Saw Yield (%) Cut Time (hrs) Wire Consumption (m/wf) Multi DW sample process Wire usage Cut time 80 µm EPW 1.8 < Multi cut sample results 80 µm EPW m/wf hrs Saw Yield Cut time Wire consumption Cut Nr Multi 156

16 TCO (USDc/Wf) Multi DW vs. Mono DW Wafer TCO comparison Effect of higher Mono ingot cost Wire usage Comparing Mono and Multi ascut wafer total cost of ownership On per wafer basis, Mono wafer cost on par with Multi Effects of higher throughputs On per Watt basis, mono wafers cost can already be lower than multi Key drivers are Mono vs. Multi brick cost Wire cost Throughput effects Assumptions Mono: 70 um fast cut process; 180 um thickness; 27 USD/kg brick, Multi: 80 um EPW process; 200 um thickness; 20 USD/kg brick 16

17 Capacity (MW/yr) Multi DW vs. Mono DW Wire saw capacity comparison Multi Mono Target Capacity Higher throughputs for Mono driven by faster cutting times and higher number of wafers per mm (thickness, kerf) Nr of wire saws for Mono reduced compared to Multi Assumptions Mono: 70 um fast cut process; 180 um thickness; Multi: 80 um EPW process; 200 um thickness Nr of Machines 17

18 TCO (USDc/Wafer) Why is Quality Relevant? Wafer TCO contributors Challenge: Biggest levers for further TCO reductions Wafer thickness Yield / Inspection Quality is critical to enable further cost-downs Mono / 180 µm / 70 µm wire

19 Levers to improve slicing quality Slicing machine setup High quality inspection High quality processes Optimized handling 19

20 How to detect microcracks accurately? Transflection TFC technology Standard NVCD Technology New TFC Technology Transflection technology increases visibility of microcracks and therefore minimizes misjudge rate 20

21 65µm 175 µm 175µm Challenge edge chips / Perpendicular edge detection Perpendicular Edge Detection technology Wafer edge defect 90 µm 21

22 Near-Term Challenges (1-3 Years) Please identify/describe your top near-term challenges for the adoption of Advanced Wafering Techniques as it relates to your position in the supply chain Improving material utilization via thinner wire diameters (wires, process, machine) as well as thinner wafers Providing qualified wafers for next gen PV technologies Adoption of diamond wire slicing for Multi crystalline silicon (DW slicing, texturization)

23 Long-Term Challenges (4+ Years) Please identify/describe the top long-term challenges for the adoption of Advanced Wafering Techniques as it relates to your position in the supply chain High maturity of classical wafering technologies (high throughputs, yields, low costs) may lead to lower capex pool Industrializing alternative wafering technologies (kerf free) Need for yet higher degrees of automatization, integration and intelligence

24 Thank you for your attention Visit us at Intersolar booth 7521 West Hall 24