Photolithography

MASK ALIGNER: MA6 (KARL SUSS)

MANUAL: see file ma6.pdf

SELECT PROGRAM

Exposure type: Hard; Low Vac; Vac; Prox; Flood-E; Soft

EDIT PARAMETERS

If you choose Hard Exposure:

Process: Lithography

Exposure Time (s): It depends by the resist

Al. Gap (um): the gap between the mask and the sample

Exposure Type: Hard

Hc Wait (s): waiting time before exposure

WEC Type: Cont.

N2 Purge: IF NO

IF YES you can choose N2 Prg Time and N2 Prg Gap

WEC Offset: ON

OFF

Lamp: 350W Type: Hg

CH1: 365nm 1mW/cm2

CH2: 405nm 2mW/cm2

PHOTOMASK

Photomasks are made by JWNC Staff. To request one, send an e-mail to robert.harkins@glasgow.ac.uk.

Photomasks are 5" square Cr made by EBL. It is useful to request 1 or 2 copies of the mask. Before to start any photolithography process, it is useful to analyze the mask (and the copies) by optical microscopes in JWNC.

PHOTOLITHOGRAPHY OUTLINE

1. Clean the photomask rinsing it in an RSB water in ultrasonic bath for several time.

2. Clean the sample rinsing in acetone (first flushing substrate) then put the sample+acetone in the ultrasound bath for 5 minutes. Same procedure with

methanol (DON'T REMOVE SAMPLE FROM ACETONE BAKER) then dry the sample by N2 flow.

3. Pre-bake oven 90° for 3 minutes

4. Spin resist (positive S1800 series or positive AZ4562 resist). (Look at the files down for the spinning process)

5. Bake hot plate 115° (Look at files down for the time).

(THE HOT PLATES IN JWNC ARE NOT CALIBRATED. USE THERMOMETERS TO CHECK TEMPERATURE)

6. MA6 hard exposure (Look at files down for the time exposition).

7. Development of the sample by MF 319 for S1800 or AZ400K for AZ4562 (Look at files down for time).

8. Rinse the sample in RO water using the same time of development, then dry by N2 flow.