...
- Kathryn McGill (CNF Fellow), 6/12/15
| Table of Contents |
|---|
...
As of 10/19/16 (though truly from 2013-2014 during MoS2 work):
Chip Spinning:
- spin 4% 495
...
- @ 3000 rpm, 1000 ramp, 60 s (resist will be ~150 nm thick)
- bake @ 170 °C for 15 min
- spin 2% 950
...
- @ 3000 rpm, 1000 ramp, 60 s (resist will be ~50 nm thick)
- bake @ 170 °C for 15 min
(develop in 1:3 MIBK:IPA - see below - & lift-off in 1:1 methylene chloride:acetone)
E-beam Writing on the Nabity
...
- Measure the current in pA for
...
- all apertures you are going to use (typically, 10 µm
...
- ap => 30-40 pA & 60 µm ap => ~1000+ pA)
- Parameters common to all run files (including alignment):
- gun @ 20 kV
- 900 magnification
...
- general params:
- Non-stop writing mode ⇒ yes
- Disable automated stage control ⇒ no
- Disable digital SEM control ⇒ no
- Disable x-y focus mode ⇒ yes
- Enable global rotation correction ⇒ no
- alignment windows:
- counts of 15
...
- center-to-center
...
- spacing 50 nm
- line spacing of 50 nm
- pattern writing of fine
...
- features:
- 10 µm aperture (set in Supra system, not Nabity system)
- continuous write
...
- center-to-center
...
- spacing 5 nm
- line spacing of 5 nm
...
- 300 µC/cm^2 area dose
...
- pattern writing of large features:
- 60 µm aperture (set in Supra system, not Nabity system)
- continuous write
- center-to-center
...
- spacing 30 nm
- line spacing of 30 nm
...
- 500 µC/cm^2 area dose
*see screenshots below
Development
Development
- 45 sec in 1:3 MIBK:IPA (shake chip back-and-forth in soln) & quench in IPA; N2 dry
Liftoff
1:1 methylene chloride:acetone overnight
Walk-through
step 1 - copy gds file into this directory:
step 2 - right click to convert gds to dc2:
step 2.1 - change drawing unit size to 1 and press convert:
step 3 - right click on new dc2 file and select DesignCAD Express:
step 3.1 - click NPGS - setdump
step 3.1.1 - the dump point is green:
step 3.2 - click NPGS - MaxMag:
step 3.3 - click NPGS - save - exit when done - then re-open to double check dump existence:
step 4 - right click on dc2 - choose run file editor:
step 4.1 - for fine contacts process 2 entities - set params as shown - pattern name is name of dc2 file:
step 4.2 - 1st entity is alignment - set params as shown - insert measured beam current in pA:
step 4.2.1 - skip all non alignment layers:
step 4.3 - 2nd entity for fine contacts - skip all alignment layers - change line to area dose:
step 4.3.1 - enter params as shown - same for each layer! - skip contact pad layer - remember to update measured current
step 4.4 - save run file - extension RF6 - and exit:
step 5 - find run file - right click - process run file:
step 5.1 - click continue - the writing will start!
step 6 - set up contact pad exposure - use these params:
step 6.1 - skip all but contact pad layer - enter params - remember to update measured current - proceed as before:
