Koch Lab:Protocols/Photolithography

=Legend= "->" denotes physically pushing the button on the machine with the text that appears directly after symbol.

=General Outline of process=
 * 1) Spin
 * 2) Pre bake
 * 3) Expose
 * 4) Post bake

=Procedure= Preheat hotplate for prebaking wafer
 * ->set
 * ->plate temp
 * ->"Desired temp"
 * ->9
 * ->5
 * ->ent



Applying photo resist
 * 1) Place wafer on spin coating machine
 * 2) *->speed (input speed)
 * 3) *->accel (input acceleration)
 * 4) *->time (input time)
 * 5) *->save->back
 * 6) *->run process
 * 7) *->load recipe
 * 8) *->"file name"
 * 9) Manually center wafer by "eyeballing" it (this may take several tries)
 * 10) Turn on vacuum pump (manually)
 * 11) *->center
 * 12) Manually adjust wafer if needed (repeat previous 2 steps until wafer is centered sufficiently)
 * 13) Poor photo resist on the top side of the wafer
 * 14) *->spin
 * 15) *->ok
 * 16) **NOTE: bubbles on wafer are normal
 * 17) Move wafer to hot plate
 * 18) *wait 15 minutes
 * 19) Hook up vacuum hose to UV exposer
 * 20) Turn on Nitrogen
 * 21) UV exposer
 * 22) *Pull white lever
 * 23) *->start
 * 24) *wait for 200W
 * 25) *->Power
 * 26) *->visual align
 * 27) *Tape mask onto glass (place glass side up)
 * 28) **->mask clamp
 * 29) *Load wafer on tray below
 * 30) **->chuck vac
 * 31) *Push slide in
 * 32) **->mask load
 * 33) **->visual align
 * 34) **->wafer load
 * 35) **->cont (pushes wafer against mask)
 * 36) *Set time
 * 37) **->manual expose
 * 38) *->chuck vac
 * 39) *remove wafer
 * 40) Post bake (5 mins)
 * 41) *->mask load
 * 42) *->mask clamp
 * 43) Take off slide
 * 44) Turn everything off!!!
 * 45) Place wafer in glass dish
 * 46) *NOTE: It is imperative that glass is used, if a petri dish is used the developer with fuse the wafer to the dish.
 * 47) Poor in developer (6 mins)
 * 48) Take wafer out of developer
 * 49) *At this point you can spray the wafer with ethanol to remove residual developer
 * 50) *Can also use Nitrogen gas to blow off fluid/debris from wafer
 * 51) Dispose of developer in designated bottle under fume hood.