This is good information on using AZ5214E, Thomas.  This resist
contains a compound (I don't know exactly what it is) that neutralizes
the carboxylic acid formed during exposure, and therefore performs the
same function as the ammonia.  When I used it years ago, the PEB time
and temperature were very finicky, and therefore difficult to control
in a production environment.  Perhaps they have improved the
formulation in the intervening time.

Brad Cantos
brad.cantos@holage.com
http://holage.com


On Aug 21, 2009, at 5:30 PM, Wilson, Thomas wrote:

> Here's one foolproof recipe for patterning sputtered metallization
> layers (on silicon) as thick as 500-nm using image reversal with
> AZ5214E (no YES oven used) and requires no dry etching.
>
> Acetone+Methanol spin rinses followed by drying spin (you may also
> wish to do a piranha clean first if stored in plastic chip cases for
> more than a month)
>
> Dispense AZ
> Spin at 4000 rpm 45 sec (1.4 micron)
> Use razor blade to skim off excess PR near chip edges (if other than
> wafers) - this prevents chip sticking to photomask during soft
> contact exposure!
> Pre-bake 100 C 60 sec
> Expose 320 nm @ 50 mJ (using MA-6 in soft contact mode => 3 micron
> lines are easy).
> Post-bake 117 +/- 2 C @60 sec
> Flood Expose: 1 Joule at 365 nm AOI
> Sputter up to 500 nm thick metal (I haven't pushed it to higher
> thicknesses)
> Lift-off: Acetone soak 15 min, followed by 1-2 min sonication with
> acetone in beaker floating in water bath of ultrasonicator
>
> Thomas Wilson
> Department of Physics
> Marshall University