450mm Innovations and Synergies for Smaller Diameters Dr. Mike Czerniak, Global Product Manager, Edwards EMS Business Presented by Steve Cottle,

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1 450mm Innovations and Synergies for Smaller Diameters Dr. Mike Czerniak, Global Product Manager, Edwards EMS Business Presented by Steve Cottle, Senior Product Manager, Edwards EMS, Clevedon, UK

2 Contents Introduction New process innovations and the challenges they pose for pumps and abatement Solutions for o III-V transistor channels o 3D memory o Rare earth metals o EUV Summary & conclusions

3 Introduction Many new processes are currently being developed and introduced These are to improve the performance of logic and memory devices, to shrink feature sizes, and to reduce power consumption These pose additional challenges for pumps and abatement systems Fortunately solutions exist for 300mm and 450mm diameter wafer production

4 New process innovations : III-V transistor channels in Silicon Courtesy IMEC III-Vs have significantly higher electron mobilities than Si or SiGe This enables higher speed transistors and lower power consumption (= longer battery life)

5 III-V challenges for pumps and abatement Hydrogen is explosive and is difficult to pump (very small molecule) Arsine & phosphine are flammable and toxic They decompose to form solid arsenic & phosphorus which can cause blockages Metalorganics are flammable and can cause hydraulic lock of vacuum pumps A 2007 fire of a train carrying phosphorus in the Ukraine; phosphorus is pyrophoric A well-known hydrogen fire ignited by static discharge A Metalorganic fire test; pyrophoric just requires the addition of air

6 III-V: Vacuum Solutions ixh pump can run at very high temperatures with distributed purging to keep volatile material dilute and in the gas phase H 2 throughput curves illustrated Temperature Management System (TMS) heats exhaust pipes to minimise risk of solids condensing illustrated by photo after 5 years operation without maintenance intervention

7 III-V: Abatement Solutions Atlas Helios & Nova combustion abatement systems decompose toxic & flammable gases to <TLV & <LFL Wet Electro-Static Precipitator (WESP) removes residual oxide powders from exhaust extract >99% uptime demonstrated on full-scale LED 24/7 manufacturing applications 3 rd party fab uptime data over 12-month period

8 New process innovations: 3D memory High k dielectrics Atomic Layer Deposition, ALD 3D structures - many (deep) etch steps and multiplicity of materials to etch through

9 3D Memory P-BiCS Cell Array Structure Deposition Steps in Cell Processing Planar FG # 3D P-BiCS CT # FG Poly-Si LPCVD IPD LPCVD or ALD CG Poly-Si LPCVD 1 CG Poly-Si CVD N 1 CG-CG Inter SiO CVD N 1 Memory ONO LPCVD 1 CG Metal PVD 1 Channel Poly-Si LPCVD 1 CG HM SiN PECVD 1 (CG Pad RIE HM PECVD) CG Silicide Metal ALD? N/32 1 Planarize SiN LPCVD 1 P-BiCS Unit Cell Planarize SiO SACVD 1 SG Poly-Si LPCVD 1 SG Cap SiO LPCVD 1 SG Channel SiO LPCVD 1 Etch Steps in Cell Processing Process step numbers N will be for P-BiCS production stage. Vacuum importance increases with stacked cell layer numbers for 3D NAND. SG Channel Poly-Si LPCVD Planar FG # 3D P-BiCS CT # FG (x) Poly-Si 1 Memory Hole SiO/Poly N IPD Shunt 1 (CG Pad HM Slim Ash) N CG HM SiN 1 CG Pad SiO/Poly N CG Metal 1 CG Slit-Cut SiO/Poly N CG Poly-Si 1 SG Line SiO/Poly 1 FG (y) Poy-Si 1 SG Hole SiO/Poly 1 1

10 3D memory challenges for pumps and abatement ALD Cross-reaction between process gases resulting in solids deposition Decomposition of process gases inside vacuum pumps, resulting in solids formation and blockages Condensation of precursors in exhaust pipework, resulting in blockages Powder accumulation inside a nonoptimised pump after 1179 hours Etch Steps Requires the use of SF 6, which is Very stable (S-F bond strength = 284 kj/mole, atmospheric half-life of 3200 years) A very strong global warmer (GWP 100 = 23900) Multiplicity of by-products from the various layers being etched SEM photo of ALD by-product powder

11 3D memory: Vacuum Solutions for ALD ixh pumps designed to transport solids efficiently through the mechanism A wide range of temperature control allows tuning to the sweet-spot Too cold = condensation Too hot = unwanted reactions Progressive introduction of N 2 purge throughout mechanism reduces the partial pressure of reagents & risks of condensation & reaction

12 3D memory: Abatement Solutions Heating with Temperature Management System (TMS) minimises condensation in connecting pipework Combustion abatement (Atlas Etch) can remove SF 6 with 99.8% efficiency, even at slm flows

13 New process innovations: Rare earth Metals: Abatement Challenges High k gates are required for high speed transistors These may employ rare earth metals such as Hf, Zr, Ta ALD again It is usually necessary to remove such rare earth metals from abatement waste water

14 Rare earth Metals: Vacuum & Abatement Solutions Deposition of rare earth metals is usually performed using ALD, which has already been discussed Metals recovery system for waste water using Edwards technology Combustion abatement offers an effective route to rare earth precursor treatment This results in metal oxides in the waste water These can be efficiently removed using technologies such as nanofiltration and ion exchange

15 New process innovations: Extreme UV (EUV): Vacuum & Abatement Challenges EUV will be required for the smallest-scale patterns moving forwards Current tools require pumping and abatement of extremely high flows of hydrogen (hundreds of slm)

16 EUV: Vacuum & Abatement Solutions Hydrogen-capable pumps exist High flows of hydrogen can be readily combusted Due to safety considerations, it is desirable to house all the above in a common, extracted enclosure with common control system (Zenith) Edwards is developing technology capable of recovering hydrogen from a process exhaust stream and investigating its possible recycling

17 Summary and Conclusions A wide variety of new processes are being developed to meet the needs of next generation devices Many of these will enter HVM ahead of the introduction of 450mm wafers into mainstream chip manufacture Vacuum and abatement solutions already exist for such processes and are under further development