Fabrication of micro scale gas flow rate sensors

Fabricated devices
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Equipment

Spin coating the photoresist
  • ZEP520A photoresist
  • 3000rpm 45sec
  • Pre bake at 180°C for 3min
  • Photoresist thickness ~150nm
Spin coater and hot plate Image
Exposure
  • 15nA current
  • 350uC/sqcm
Electron beam lithography tool used to pattern the mask:JEOL JBX-6300FS Image
Develop and Cr coating
  • Developer: 90 sec in Amyl-Acetate
  • 3nm chromium layer
Kurt J. Lesker PVD 75 electron beam deposition system Image
Liftoff and Reactive Ion etching
  • Microposit®remover 1165: 80°C - 1 hour
  • Oxford Instruments Plasmalab 100
  • -100°C, 20 sccm SF6 , 5 sccm O2
Oxford Instruments Plasmalab 100 Image