TLS-Dicing for concentrator dies - a fast and clean technology. Hans-Ulrich Zühlke

Transcription

1 TLS-Dicing for concentrator dies - a fast and clean technology Hans-Ulrich Zühlke

2 TLS-Dicing with JENOPTIK-VOTAN Semi Contents Overview Jenoptik Principle of TLS-Technology TLS-Dicing the benefits at a glance Optimal cost of ownership / operational costs Machine specifications Conclusion TLS-Wafer-Dicing - Overview

3 Jenoptik Group key figures as at Dec. 31, ,400 employees worldwide of which 506 abroad of which 132 trainees Sales: million euros of which 55 percent abroad Result from operating activities (EBIT) 37.1 million euros Cashflow from operating activities: 46.5 million euros Research and development ratio 6.2 percent (without developments for customers) TLS-Wafer-Dicing - Overview

4 Lasers & Material Processing Division Corporate Center Optical Systems Lasers & Material Processing Industrial Metrology Traffic Solutions Defense & Civil Systems Optics Micro Optics Digital Imaging Optoelectronical Systems Diode Lasers Laser Systems Laser Processing Systems Surface Roughness & Contour Form & Position Measurement Dimensional Measurement Equipment Service Providing Mechatronics Optronics Sensor Systems TLS-Wafer-Dicing - Overview

5 Business Unit Laser Processing Systems Product Range TLS-Wafer-Dicing - Overview

6 Principle of TLS-Technology (Thermal Laser Separation) TLS-Wafer-Dicing - Overview

7 Principle of TLS-Technology (Thermal Laser Separation) Cross view Top view 1. Initial I-Scribe (punctiform) 2. heating (laser) pressure stress 3. cooling (aerosol/gas) tensile stress 4. complete cleaving! (time for heat conduction) TLS-Wafer-Dicing - Overview

8 TLS-Dicing with JENOPTIK-VOTAN Semi Benefits at a Glance no residues zero kerf width no chipping nearly perfekt edge works for: GaAs /Ge Si (Semi & PV) SiC TLS-Wafer-Dicing - Overview

9 Ge-sample (blank, 2000 X 2000 X 150 µm³) Sample: SolarTec International AG TLS-Wafer-Dicing - Overview

10 Wafer dicing task & relevant parameters wafer is mounted on film frame, stored in magazines front-end processes are completed high added value! product specific parameters street width passive regions on the die die size wafer thickness TLS-Wafer-Dicing - Overview

11 Basic conditions and limits for TLS-Wafer-Dicing TLS depends on heat conduction increased laser-power / more cooling doesn't increase speed (but to much laser power can damage the surface!) upper limit for wafer thickness: by now* 675 µm for GaAs / Ge TLS needs a expanded / shrinked volume lower limit for w.thickness: by now* 50 µm *) limits not finally tested TLS depends on optical properties for Si / Ge / GaAs a NIR-laser is optimal reflective layers at the surface critical dopands o.k. Sample: SolarTec International AG TLS-Wafer-Dicing - Overview

12 Properties of the TLS-process TLS works independent of the lattice plane 0 to lattice plane 60 to lattice plane 150 to lattice plane demo-circle (Ø 50 mm), Si, 150 µm TLS-Wafer-Dicing - Overview

13 Properties of the TLS-process back side metal cleaved surface works with (thin) back side metal no pealing! T-cuts possible (multi-project wafers) TLS-Wafer-Dicing - Overview

14 Known technologies for wafer-dicing established mech. saw ablating laser Water Jet Stealth dicing Invest / running cost / / / / / particles / water / / / / / damage / HAZ / / / / / kerf / street width / / / / / TLS speed <200 / >200 µm (depends on thickness) / / / / / TLS-Wafer-Dicing - Overview

15 Workflow within the TLS-dicer What is fast scribe? I-Scribe X Cleave X I-Scribe Y Cleave Y I-Scribe-diamond I-Scribe-laser I-Scribe-laser (on-the fly ) die Chuck moves with 100 mm/s Standard-Scribe diamond / laser die Chuck moves with 300 mm/s Fast-scribe-laser TLS-Wafer-Dicing - Overview

16 Higher Throughput - by increased Dicing Speed Wafer thickness (µm) TLS-Wafer-Dicing - Overview

17 Cross cuts of different laser cutting technologies Cross cut (SEM): a) standard dry laser b) laser micro jet c) laser chemical etching d) TLS (source a, b, c: IWMH) (d) TLS-Wafer-Dicing - Overview

18 Edge quality bending strength Excellent bending strength increased yield thinner products possible flexible products robust handling TLS-Wafer-Dicing - Overview

19 Cost of ownership / operational costs ( semi view ) Saw: cleaning step tool wear Stealth dicing: none TLS: drying / (none?) Laser: protective coating cleaning step remove coating maintenance of laser Laser (water jet): protective coating drying special tape high-press. pump TLS-Wafer-Dicing - Overview

20 TLS-Dicing with JENOPTIK-VOTAN Semi Machine Specifications for 150 / 200 mm-wafers (soon 300 mm) full automatic cassette handling mechanical repeat accuracy: ±3 µm clean room class ISO 6 footprint: 1900 X 1900 mm² laser: 200 W / NIR / cw mode / MTBF h TLS-Wafer-Dicing - Overview

21 TLS-Dicing with JENOPTIK-VOTAN Semi Machine Specifications Laser Robot handling for magazines Cutting system Optical system I-Scriber Chuck (rotatable) Granite structure including axis Alignment camera Cooling nozzle TLS-Wafer-Dicing - Overview

22 TLS for PV wafer and Cells damage Cutting small cells from defect taller### cells Cutting cells into small stripes Reduction of the current by serial connection Edge isolation incl. mechanical optimaisation by TLS Edge Improvement for the blank TLS-Wafer-Dicing - Overview

23 TLS-Dicing with JENOPTIK-VOTAN Semi Higher yield by reduced dicing street Clean process No short circuits / shunts due to smooth edges Less breakage within production Free-form-cutting Gentle### to thin wafers TLS-Dicing is the way to excellent cleaving results in combination with higher yield and throughput. TLS-Wafer-Dicing - Overview

24 Special thanks to: Project partners Infineon Austria and Fraunhofer IISB Erlangen Fraunhofer IOF (Jena) and IWMH (Halle /S.) SolarTec International AG (Mr. M. Sturm) Project funded by EC (project IST ) TLS-Wafer-Dicing - Overview

25 Thank you for your attention! Any questions? Visit us in Hall A2, Booth 666 TLS-Wafer-Dicing - Overview