SPR 220 7.0

SPR 220 is our most commonly used photoresist, especially for RIE. The lab stocks SPR 220 (3.0) for general use, in the ACS 200 cluster tool, and in the CEE 200X photoresist spinner 2. For films thicker then 5µm SPR 220 (7.0) is also available from the LNF Store and in the CEE 200X photoresist spinner 1.

Process

1. Dehydrate and apply HMDS
2. CEE 200X photoresist spinner 1, 10um recipe
3. Soft bake
   • Use 2 Hotplates - 30 seconds @ 90°C, 6 minutes (360 seconds) at 115°C. Move quickly between hotplates to wafer does not cool.
   • Let sample cool in a cassette or somewhere it can cool slowly. NOT on cold metal table.
4. Wait ≥ 20 min
5. Expose
   • MA/BA 6 - Aligner -26 sec (silicon)
6. Wait ≥60 min
7. Bake 115°C for
   • Use 2 Hotplates - 30 seconds @ 90°C, 3 minutes (180 seconds) at 115°C. Move quickly between hotplates to wafer does not cool.
   • Let sample cool in a cassette or somewhere it can cool slowly. NOT on cold metal table.
8. Develop
   • ACS - AZ300 - ?? sec
   • CEE - AZ726 DP 80-80 sec

Characterization

Wait time between Exposure and Post Exposure Bake

There are still some bubbles after 50 minutes so wait time needs to be greater than 50 minutes.

Post Exposure Bake

Develop