Ebeam Resist Recipes

Ebeam resist can be slightly more complicated than the typical photoresists we use, such as AZ 5209, AZ 5214, or AZ 2020. The resist is often diluted to different levels, in order to achieve different resist thicknesses.

And for each different solution concentration, the respective thickness vs RPM curve, baking time, and dose might also change accordingly. Be sure to do a dose test, if things look iffy on the early tries.

• ma-N (https://www.microresist.de/en/produkt/ma-n-2400-series/),
  ma-N 2401: ma-T 1090 = 1:1 volume ratio (expected thickness = ~240 nm)  (mr-T 1090? for ma-N 2400 = ma-N 2401 dilution) 

  • (Optional, but recommended for PECVD silicon nitride on III-V material)
    >3 min bake @ >100 degrees C, and then immediately spin
    HMDS, 1 min @ 5K RPM
  • ma-N,  1 min @ 5K RPM
  • Bake 90s @ 78 degrees C. 
  • Reference dose : 100 - 120 uC/cm^2.
  • Develop: MF321
    • Develop time is highly dependent on feature size

• PMMA a4

  • 1 min @ 3k RPM
  • Bake 2min @ 150 degrees C
  • Reference dose: 300 - 420 uC/cm^2
  • Develop: 15s @ (MBK:IPA = 1:3)
    • This is said to over-develop rather easily, so try to keep developing time constant and instead play with the exposure.

• ZEP (https://www.zeon.co.jp/en/business/enterprise/electronic/imagelec/)

  • Thinner: Anisole (https://www.nanophys.kth.se/nanolab/resists/zep520a-7-2.pdf)
  • 1 min @ 2k RPM
  • Bake 3min @ 180 degrees C
  • Reference dose: 100 uC/cm^2
  • Developer: 2min @ (n-athtate)
    (Can pour developer back to bottle after use)

• ZEP 2 Zuoming 2021.11.30 Group Meeting

  • 1 min @ 2.5k RPM
  • Bake 2min @ 180 degrees C
  • Dose 90 uC/cm^2