Maskless Aligner (Heidelberg MLA150)

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Maskless Aligner (Heidelberg MLA150) Tool Type Lithography Location Bay 6 Supervisor Biljana Stamenic Supervisor Phone (805) 893-4002 Supervisor E-Mail biljana@ece.ucsb.edu Description Maskless I-Line Photolithography Manufacturer Heidelberg Instruments Model MLA150 Materials I-Line Photoresists

About

The MLA150 allows for arbitrary direct patterning of I-Line photoresists, directly from an uploaded CAD drawing/file (GDS, DXF, CIF etc.). The system uses a digital micromirror device ("DMD", an array of MEMS mirrors) for patterning the exposure light-field, to programmatically expose digitized patterns directly onto the sample - no glass photomasks/reticles are required.

The system has a continuous, automatic autofocus, using either a pneumatic or optical detection. This enables lithography on non-planar or curved substrates. We also have the high-aspect ratio (variable/long focal length) option installed for very thick (~70µm) photoresists.

Depending on the exposure options and write area, the MLA is able to expose a 100mm wafer in about 30min, and achieves minimum features sizes around 0.5µm, with overlay/alignment accuracy better than 200nm. Arbitrary drawings can be exposed onto any feature located on the microscope.

Greyscale lithography is capable of producing repeatable slanted or tapered structures in photoresist or photo-active dielectrics like SU-8.

Detailed Specifications

• Wafer size:
• Wafer / substrate thickness: Max. 9mm.
  • Thicker is possible, contact supervisor.
• Exposure optics:
  • Digital micromirror device (DMD)
  • Laser #1: 375nm
  • Laser #2: 405nm
• Alignment Accuracy: ≤ 200nm

• Additional manufacturer options:
  • High-resolution option (Write Mode 1)
  • Extended Focus Range
  • Variable Focal Depth
  • Optical (laser) Autofocus in addition to Pneumatic Autofocus

Documentation

Operating Procedures

• MLA150 - Standard Operating Procedure

Video Trainings

• Part 1: Overview and basic usage
• Part 2: Focus Exposure Matrix (FEM)/Series
• Part 3: Local "Field" Alignment

Design Tools/Info

• MLA150 - Design Guidelines
• MLA150 - CAD Files and Templates

Recipes

• Recipes > Lithography > Maskless Aligner MLA150
  • Starting recipes for various I-Line photoresists