Authorized Materials

Summary of material constraints

Lab members wishing to introduce new materials into this system must first obtain authorization from staff. New material requests must be initiated by submitting a Process Review Request form.

Non compliance will result in loss of member privileges

Authorized Substrates

  • silicon
  • III-V semiconductor materials such as GaAs, InP, etc.
  • ZnSe


  • FR-4 Circuit board
  • Any substrate not specifically authorized above is NOT PERMITTED

Authorized Films

  • typical, fully baked, e-beam resists such as PMMA, ZEP, HSQ, etc.
  • The table below represents minimum recommended baking times and temperatures for common resists. Baking at lower temperatures and/or shorter durations is not permitted without written consent from Fab staff.
  • In order to ensure consistency of baking temperature, all local users are required to bake their resist at the QNFCF.
Resist Temperature on hotplate (°C) Duration (s)
PMMA 180 180
MMA(8.5)MAA copolymer 150 180
ZEP520A 180 180
HSQ 80 240
  • Resist stacks (multiple resists) must be baked at recommended conditions (or longer) following each individual spin step.
  • Please consult staff for resist stacks containing 3 or more component layers.
  • Nitrocellulose e-beam resist on an evaluation basis
  • dielectric films: silicon dioxide, silicon nitride, Al2O3
  • Chrome, aluminum, gold, titanium
  • ZnSe


  • Any film not specifically authorized above is NOT PERMITTED
  • Any film that is not fully baked is prohibited: remaining solvent will degas in the system and may trip off and damage the Schottky emitter.