SU 8 EBL - NanoLabStaff/nanolab GitHub Wiki

by Jonas M. Ribe

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1. Spin coat SU-8 2

    6000rpm for 30s
    Ramp: 300rpm/s (+20s)
   

2. Soft bake

    1min at 65°C
    2min at 95°C
   

3. Exposure (EBL)

    Features: Areas
    HV: 30kV
    Current: 24pA
    Dose: 0.60μC/cm^2
   

4. Post-exposure Bake

    1min at 65°C
    Ramp hot plate to 95°C 
    2min at 95°C
    Turn off hot-plate and leave sample until it has reached room temperature (~40min). (Rapid cooling should be avoided).
   

5. Develop

    ~1 min in mrDev 600 (under agitation)
    Rinse in fresh developer
    Rinse in IPA
    Dry w. N2 (g)
   

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SU-8-EBL-C.jpg
SU-8 dose matrix

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by Kai S. Beckwith

This is my protocol for exposing various nanostructures and microstructures of SU-8. It is quite similar to Jonas', but I post it here for reference anyway.

See page Dilution-of-SU-8-2000-series for recipe of how to make different thicknesses of SU-8. See also this process information on LIMS for general tips on using the EBL.

0. Clean substrate (glass, silicon, others)

    Rinse with acetone, IPA and DIW, blow dry.
    Plasma clean 30s O2/50/50
    Rinse again with acetone, IPA and DIW, blow dry.
    Leave on 95°C for 2 minutes, place on cold plate for 1 minute.
   

1. Spin coat SU-8 2000

    6000rpm for 36s
    Ramp: 1000rpm/s
   

2. Soft bake

    1min at 95°C
    Leave on cold plate 2 minutes before going to EBL.
   

3. Exposure (EBL)

    Note: The doses vary by resist thickness, 
    these are good for 1µm. For thinner resists 
    slightly smaller doses may be used, 
    but the below doses work fine as well.
   
   
    Features: Areas
    HV: 30kV
    Current: 100-500pA
    Step size: 0.1µm
    Dose: 1μC/cm^2
   
    Features: Curves
    HV: 30kV
    Current: 100-500pA
    Step size: 0.05µm
    Dose: 1.5μC/cm^2
           
    Features: Single-pixel dots/pillars
    HV: 30kV
    Current: 100pA
    Dose: 2000-2500aC
            
    Features: Single-pixel lines
    HV: 30kV
    Current: 100pA
    Dose: 50-60pC/cm
   

4. PEB:

    1min at 95°C
    1min on cold plate
   

5. Develop

    ~1 min in mrDev 600 (under agitation)
    Rinse in fresh developer
    Rinse in IPA
    Dry w. N2 (g)
   

Expected results: for the single-pixel exposures about 50-100 nm features are expected, depending on resist thickness. Areas should be well-defined with sharp edges.

Discuss this protocol!