Difference between revisions of "SOI grating definition"

Revision as of 19:20, 27 October 2011

Current Processes

Sweeper Vertical Grating Coupler Process

   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

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 (INCOMPLETE)

   Standard Process
       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
   Add PR protection layer
       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 (NEEDS CALIBRATION)
           Focus Offset: 0 (NEEDS CALIBRATION)
           NO POST-EXPOSURE BAKE
           Develop (AZ400K 1:4 diluted, 1min)
           DI Rinse
   Grating Partial Etch - Etch the difference in depths (deep target - shallow target)      
           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 PR protection layer        
       Strip AZ4210 in ISO - Should not attack ZEP(2:1)
   Grating Shallow/Finish Deep Etch - Etch the difference in depths (deep target - shallow target)      
           AFM etch depth calibration recommended   
           Single step Bosch etch process - JTB_GR
           Rates: ~170nm/min w/o Sanovac 5, ~141nm/min w/ Sanovac 5