GCA AS200 AutoStep

GCA AS200 AutoStep
Equipment Details
Technology	Projection lithography
Materials Restriction	Semi-Clean
Material Processed	All LNF approved photoresists
Mask Materials	5"
Equipment Manual
Overview	System Overview
Operating Procedure	SOP
Supported Processes	Supported Processes
User Processes	User Processes
Maintenance	Maintenance

The GCA AS200 AutoStep is a submicron capable projection lithography 5X reduction exposure system. The system can automatically perform all wafer processing and handling operations of 4" wafers and can be used to align and expose pieces. It is primarily used to expose an array of images directly onto the surface of a wafer.

Announcements

LNF is now under contract with SCS, Inc. They will be servicing and optimizing our system over the course of the next year or so. They have stated they can achieve 0.5 μm resolution across field with local alignment accuracy better than 0.25 μm once repairs and optimization are completed. LNF staff will keep users posted. Testing and new operating procedures are under way.

Capabilities

• 0.75 μm resoution across field(current-see announcement) 0.5 μm overlay accuracy (current)
• 10 mm pieces up to 6" wafers
• Substrate thicknesses (with existing chucks) 175-675 μm (the range from 400-475 μm thick may not work)
• 14 mm max die size (current)
• High resolution/high precision mask making possible if there's interest

System overview

Hardware details

• 5x reduction i-line(λ = 365 nm) stepper.
• Lens: Tropel 2145: 21 mm circular field on wafer, NA = 0.45
• Constant power light source corrected to about 500 mJ/sec
• Automatic reticle (mask) alignment. Automatic wafer handling for 4" wafers
• Atmospheric compensation system controlled to within 0.1 °C

Substrate requirements

• 10 mm pieces up to 6" diameter
• Substrate thicknesses (with existing chucks) 175-675 μm (the range from 400-475 μm thick may not work with existing chucks)
• 4" Si substrates can be autoloaded and prealigned. Various other substrates permitted, but must be manually loaded
• Mounting not necessary unless one is trying to achieve a useable thickness. Make a helpdesk ticket for assistance if needed

Material restrictions

The GCA AS200 AutoStep is designated as a Semi-Clean 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.

Approved materials

Supported processes

Exposure of all LNF approved photoresists are allowed on this tool in accordance with standard operating procedure. More data on exposure times can be found on datasheet for the specific photoresist. If you are curious if your material can be processed in this tool, please contact the tool engineers via the helpdesk ticket system.

Standard operating procedure

• Auto Load SOP
• Manual Load SOP
• Job Setup Guidelines

Templates

• Global Key
• Global Key w/ Arrows
• Layout (5X Reduction)
• Local Mark

Note: If you have questions about mask design please make a helpdesk ticket before making the mask.

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. Read through this page and the Standard Operating Procedure above.
3. If possible, practice with your mentor or another authorized user until you are comfortable with tool operation.
4. Create a Helpdesk Ticket requesting training.
5. A tool engineer will schedule a time for initial training.
6. Schedule a checkout session with a tool engineer via the helpdesk ticket system. If this checkout is successful, the engineer will authorize you on the tool.

Maintenance

The stepper is under service contract with SCS, Inc. They provide overnight parts support, 24-hour tech support, and visit twice per year for full system calibrations, stage rebuild, and overall system evaluation and tuning. Lamp changes are done bimonthly or as needed. dose calibrations and uniformity tests are done as needed. Baseline calibrations are done weekly with setup calibrations done daily or per run. Baseline wafers are flashed weekly to biweekly for resolution check and dose uniformity.