A. Blednov, M. Beaudoin (Rev. 01, August 10, 2018)

To describe the photoresist recipe used in the AMPEL Nanofabrication Facility using the AZ 5214E-IR Photoresist and matched AZ 300 MIF developer. AZ is a trademark of Clariant Corporation.

A. Wafer cleaning (optional)

1. 180 s hot acetone (set temperature by boiling point of acetone)
2. 180 s hot isopropanol (use same hotplate and hence temperature as boiling acetone)
3. 180 s hot DI water (use same hotplate and hence temperature as boiling acetone)
4. Blowdry with the nitrogen gun
5. Alternately, other cleaning recipes can be found on the cleanroom website www.nanofab.ubc.ca.
6. Optional step: perform a dehydration bake, either on a hotplate or in the small cleanroom oven)

B. HMDS priming (optional to promote photoresist adhesion). WARNING: waste HMDS needs to be disposed of in the appropriate waste bottle located in the yellow cabinet.

1. Pour out HMDS (hexa-methyl-di-silazane) from the 4L bottle into a small beaker. The bottle is kept in the flammables cabinet.
2. Set spinner control to 4000 rpm and 40 s
3. Using a clean disposable glass pipette, aspire HMDS from the beaker.  (Alternately, you may skip step 1 and pipetted directly from the bottle; make sure not to pour back excess HMDS into the bottle)
4. Dispense onto center of wafer (avoid bubbles).
5. Spin wafer
6. Allow to air dry for at least 1 min.

C. Photo Resist

1. Set Hot plate to 98 °C and wait until equilibrated (alternately, the ovens between 90-95 °C can be used instead); NB: this is a guideline.
2. Set spinner control to 4000 rpm and 40 s and high acceleration (20000 rpm/s is good)
3. Dispense photoresist (PR) onto center of wafer (avoid bubbles) using a disposable glass pipette

a. To dispense, use one of the small brown bottles and take it to the wetbench without disturbing the contents
b. Use a clean pipette and suck the photoresist from the top of the liquid: avoid taking it from the bottom of the bottle as deposits usually form there. Dispose of pipette in sharps container.

4. spin wafer
5. Swab wipe corners/edges with acetone to remove PR meniscus
6. Bake on Hotplate for 60 s (1 min).
7. Allow to cool for at least 3 min.

D. Photolithography

1. Place in Mask Aligner and Follow SOP for the chosen aligner
2. Exposure with a dose of 90 mJ/cm2; On the NxQ4006 aligner, 8s is the current exposure time (August 2018) but this may change with time so make sure to confirm with cleanroom staff.

E. Develop using AZ 300 MIF

1. 40-45 s
2. rinse in DI water
3. Blowdry with the nitrogen gun

Optional Steps
F. Hard bake

1. 60s (or more) at 110 °C
2. Can be done on hotplate or oven.

G. For image reversal process (skip step E)

1. After step D, perform post exposure bake (PEB) at 110 °C for 45s
2. Perform a flood exposure for 1s using the mask aligner
3. Go back to step E and develop.