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Equipment Details
Technology Contact lithography
Materials Restriction General
Material Processed LNF approved photoresists
Mask Materials 4" masks (smaller possible with tool engineer discussion)
Sample Size small pieces up to 3" diameter
Equipment Manual
Overview System Overview
Operating Procedure SOP
Supported Processes Supported Processes
User Processes User Processes
Maintenance Maintenance

The MJB3-2 is primarily used to expose photo-definable materials on small pieces up to 3" in diameter. It only accepts 4” hard masks or smaller. Transparencies, shadow masks, or flood exposure can also be used.


  • 4-5 µm min feature size resolution in thin resist
  • Aspect Ratio 1:3 possible
  • Substrate thickness 200 µm to 4 mm possible

System overview

Hardware details

  • Broadband light source calibrated to 20 mJ/sec at the 405 nm peak. Total broadband dose about 30 mJ/sec
  • piece chucks and 3" chuck
  • 3", and 4" mask holder
  • Flood exposure, soft, hard, and vacuum contact capable (for details, see SOP)
  • Capable of topside alignment only
  • 10 mm stage travel, 75 mm microscope objective travel

Substrate requirements

  • Full 3" and wafer pieces standard
  • Mounting may be necessary if wafer has thru holes, etc. Create helpdesk ticket for assistance
  • Substrate thickness 200 µm to 4 mm possible
    • Thicker substrates or PDMS may be used with tool engineer approval

Material restrictions

The MJB3-2 is designated as a General class tool. Below is a list of approved materials for the tool. Approved means the material is allowed in the tool under normal circumstances. If a material is not listed, please create a helpdesk ticket or email info@lnf.umich.edu for any material requests or questions.

Supported processes

Please get staff assistance through the lithogrpahy training session or lithopraphy handbook, or see material datasheets for your photoresist.

Standard operating procedure


Checkout procedure

  1. Complete a Lithography training session. If you have already completed this for another tool, you do not need to complete it again.
  2. Practice on the tool with your mentor.
  3. Read through the User Manual above.
  4. Accurately complete the checkout quiz. You may retake as necessary until all answers are correct.
  5. Schedule a time for a checkout:
    1. Find an available time for checkout here.
    2. Verify that the tool is available in the LNF Online Services at the time you are requesting.
    3. After confirmation that the event is scheduled in Calendly, invite the staff member assigned to your event to a Staff Support reservation at that time.
  6. Create a helpdesk ticket for final confirmation of your checkout appointment.
  7. Authorization will be provided pending demonstration of proper tool use in the presence of a tool engineer.


The UV energy at the chuck face is routinely calibrated, so that the energy delivered corresponds to the display on the lamp controller. The energy delivered is 20 mJ/sec at the 405 nm wavelength with an additional 9-10 mJ/sec at the 365 nm wavelength (the 365 nm peak is not calibrated, but is constant in relation to the 405 nm peak). Lamp uniformity is routinely calibrated to within 2-3% across the 75 mm range. The WEC (Wedge Error Compensation) head is completely rebuilt semi annually and checked weekly and adjusted as needed for proper height and level.