Difference between revisions of "SOI grating definition"
From OptoelectronicsWiki
(→Sweeper Two Etch Depth Grating Process (UNTESTED)) |
(→Sweeper Vertical Grating Coupler Process) |
||
Line 1: | Line 1: | ||
Back to [[Process_Hybrid_Silicon]]. | Back to [[Process_Hybrid_Silicon]]. | ||
==Past Processes== | ==Past Processes== | ||
− | ===Sweeper Vertical Grating Coupler Process=== | + | ===Sweeper Vertical Grating Coupler Process (ZEP:Anisol(2:1) Soft mask, limited to shallow ~150-200nm Si gratings, used in SWEEPER for gratings <100nm)=== |
Pre-clean: Remove native oxide and/or dielectric hardmask | Pre-clean: Remove native oxide and/or dielectric hardmask | ||
HF dip | HF dip |
Revision as of 14:47, 8 April 2012
Back to Process_Hybrid_Silicon.
Contents
Past Processes
Sweeper Vertical Grating Coupler Process (ZEP:Anisol(2:1) Soft mask, limited to shallow ~150-200nm Si gratings, used in SWEEPER for gratings <100nm)
Pre-clean: Remove native oxide and/or dielectric hardmask HF dip Ebeam PR spin coat (2:1 ZEP) ACE,ISO,DI PEII - O2 Descum (100W, 300mTorr, 60sec) Dehydration Bake (150C, 5min) N2 Gun (1min) Cools and cleans wafer Spin 2:1 ZEP (3000rpm, 30sec) - Recipe 5 ~225nm, Use a filtered syringe Pre-Exposure Bake (180C, 4min) Cover hotplate top to prevent additional particulate Thermal Au Evaporation Evaporate 11nm Au Ebeam Writing Conditions 4th Lens Dose 350uC/cm2 (Please be aware this is pitch dependent, but has shown good results over a range of pitches if the substrate is not highly doped) Development Remove Au in wet Au etchant 10s DI Rinse N2 Dry 1:1 MIBK:ISO Development - 60s Use a fresh batch 9:1 MIBK:ISO Rinse - 15s DO NOT RINSE WITH DI N2 Dry DO NOT RINSE WITH DI Grating Etch AFM etch depth calibration recommended Single Step Bosch Etch Process - JTB_GR Rates: ~170nm/min w/o Sanovac 5 ~141nm/min w/ Sanovac 5 Strip ZEP (2:1) 1165 Soak at 80C - 10min PEII - O2 Descum (100W, 300mTorr, 60sec)
Standard Hybrid Si Process
link to .xls
Process Development Summary
Dose/Duty Cycle Analysis with Proximity Effect Observations
File:2010-03-01 Grating Update.pptx
File:2010-12-07 Grating Update.pptx
Future Untested Processes
Sweeper Two Etch Depth Grating Process (UNTESTED)
Oxide Hardmask Deposition - PlasmaTherm PECVD 50+50nm SiO2 Add Si watch sample VASE Si Watch Sample - Note Oxide Height Cr Deposition - Ebeam #1 100nm - This is a value that has been calibrated, but there would be value in using 25nm to decrease the undercut Add a watch sample with orange vacuum tape in the middle Dektak the watch sample after removing tape Oxide Hardmask Deposition - PlasmaTherm PECVD 50nm SiO2 Add Si watch sample VASE Si Watch Sample - Note Oxide Height Ebeam Resist spin coat (2:1 ZEP) ACE,ISO,DI PEII - O2 Descum (100W, 300mTorr, 30sec) Dehydration Bake (150C, 5min) N2 Gun (1min) Cools and cleans wafer HMDS 5000rpm 30s - Let sit on chip for 30s before spinning Spin 2:1 ZEP:Anisol (3000 rpm, 30sec) - Recipe 5 ~225nm, Use a filtered syringe Pre-Exposure Bake (180C, 4min) Cover hotplate top to prevent additional particulate Conductive polymer spin coat Aquasave (3000 rpm, 30sec) - Recipe 5 Pre-Exposure bake (90C, 30sec) Ebeam Writing Conditions 4th Lens - 2nA Dose 500uC/cm2 (Please be aware this is pitch dependent, but has shown good results over a range of pitches with a ~45nm undercut in the 100nm of Cr) EBL Development DI Rinse - 60s Removes Aquasave N2 Dry - Be gentle the resist can move under high pressure 1:1 MIBK:ISO Development - 60s Use a fresh batch 9:1 MIBK:ISO Rinse - 15s DO NOT RINSE WITH DI N2 Dry DO NOT RINSE WITH DI - Be gentle the resist can move under high pressure Microscope Inspection - AFM Pattern Acknowledgement - Hardmask Etch - ICP#2 O2 Clean - 10min 2min season - ICP#2 recipe #104 - CF4/CHF3/02 - 5/35/10sccm - 500Wicp, 50Wccp, 0.5Pa Oxide Nano Etch - ~80nm/min - over etch 25% (50s for 50nm) ICP#2 recipe #104 - CF4/CHF3/02 - 5/35/10sccm - 500Wicp, 50Wccp, 0.5Pa Strip ZEP:Anisol (2:1) 1165 Soak at 80C - 10min PEII - O2 Descum (100W, 300mTorr, 60sec) AFM Pattern Acknowledgement - Save grating cross-sections confirm height with oxide thickness measured earlier Cr Etch - ~35nm/min - over etch 25% (3m45s for 100nm) ICP#2 recipe #145 - Cl2/02 - ?/?sccm - ?Wicp, ?Wccp, ?Pa AFM Pattern Acknowledgement - Save grating cross-sections confirm height with Cr and top oxide thickness measured earlier Oxide Nano Etch - ~80nm/min - over etch 25% (100s for 100nm) ICP#2 recipe #104 - CF4/CHF3/02 - 5/35/10sccm - 500Wicp, 50Wccp, 0.5Pa AFM Pattern Acknowledgement - Save grating cross-sections confirm height with Cr and lower oxide thickness measured earlier top oxide should be gone. Grating Shallow Etch - Si Deep RIE Etcher (50nm) Chamber Prep (no sample): O2 Clean - 30min - Click standby, then enter manual mode. (the electrode temp must be with in bounds to enter standby mode) Load Clean wafer. Parameters 10C,30mTorr,He=10,Ar=10,O2=30,Power RF2=800 2min season - BOV_J_01 - C4F8/SF6/Ar = 56/24/20sccm @ ICP/CCP = 850/18W Single step Bosch etch process - BOV_J_01 - C4F8/SF6/Ar = 56/24/20sccm @ ICP/CCP = 850/18W Rates: ZEP ~ 35-40nm/min, ~63-141nm/min w/ Sanovac 5 AFM Pattern Acknowledgement - Save grating cross-sections Cr mask will show a negligible etch so the Si depth should be clear. Add GRAT1 layer (Protects Sweeper gratings) Spin AZ4210 (4000rpm, 30sec) Pre-Exposure Bake (95C, 1min) Lithography - Pattern a window in the deep etch region Litho Tool: GCA Stepper / Autostepper Exposure: 3sec / 1sec Focus Offset: 0 NO POST-EXPOSURE BAKE Develop (AZ400K 1:4 diluted, 2min(way over-developed) DI Rinse PEII - O2 Descum (100W, 300mTorr, 30sec) - Do not repeat this because this oxidizes the Cr and will enlarge the grating pattern Microscope Inspection - Grating Finish Deep Etch - Etch the difference in depths (deep target (275nm) - shallow target (50nm) = 225nm) AFM etch depth calibration recommended Chamber Prep (no sample): O2 Clean - 30min - Click standby, then enter manual mode. (the electrode temp must be with in bounds to enter standby mode) Load Clean wafer. Parameters 10C,30mTorr,He=10,Ar=10,O2=30,Power RF2=800 2min season - BOV_J_01 - C4F8/SF6/Ar = 56/24/20sccm @ ICP/CCP = 850/18W Single step Bosch etch process - BOV_J_01 - C4F8/SF6/Ar = 56/24/20sccm @ ICP/CCP = 850/18W Rates: ZEP ~ 35-40nm/min, Si ~170nm/min w/o Sanovac 5, ~63-141nm/min w/ Sanovac 5 Strip PR 1165 Soak at 80C - 10min PEII - O2 Descum (100W, 300mTorr, 60-120sec) AFM Pattern Acknowledgement - Save grating cross-sections from AFM test structure shallow and deep Cr Etch - ~35nm/min - over etch 25% (3m45s for 100nm) ICP#2 recipe #145 - Cl2/02 - ?/?sccm - ?Wicp, ?Wccp, ?Pa AFM Pattern Acknowledgement - Save grating cross-sections from AFM test structure shallow and deep BHF Dip AFM Pattern Acknowledgement - Save grating cross-sections from AFM test structure shallow and deep SEM - Save top down SEMs for different locations and different grating types.