Mask Fabrication

Mask fabrication is an established standard process available in the CMi CM-1 cleanroom. The process flow below describes process parameters, steps of operation and equipment used. The current process uses the Heidelberg Instruments VPG200 laser writer and the Hamatech HMR900 Mask Processor.

Step information / Cross section Equipment Recipe / Parameters

Starting material:

Commercial plates (Nanofilm) are available in standard sizes (5×5 inch for exposure on 100mm wafers, 7×7 inch for exposure on 150mm wafers, 4×4 inch for exposure on small wafers & piece parts). 6×6 inch plates for stepper reticles are available but please discuss with the CMi staff before placing an order.

Order at least 24h in advance

Laser writing:


Z5 – VPG200

  • GDS/CIF layout conversion on conversion PC (Zone 5)
  • Write parameters: Mode, Power, Defocus (Refer to the VPG Parameters page for instructions).


Development (diluted AZ 351B) & Rinse:


Cr etch & Rinse:


Resist strip (AZ 400K) & Rinse:

Z6 – Hamatech Mask Processor

Equipment preparation (purge):

  • Recipe N°8 = LINES PURGE

Mask processing:

  • Recipe N°1 = DEV/ETCH/STRIP ( 4×4 and 5x5inch)
  • Recipe N°11 = D/E/S (6×6 and 7x7inch)

Mask cleaning:

  • Recipe N°4 = KOH_strip


Z6 – Leica Microscope


Final use


Note that the image of the written data is mirrored over the Y axis.