Projection(Stepper) Lithography

GCA 6300 i-line stepper         GCA Autostep 200

We have two GCA i-line wafer steppers that use masks compatible with both systems.  System Features are:

• 5” x 5” x .09” mask size.  Special Mask Alignment Marks Available.
• 15 mm x 15 mm maximum die size
• 1 cm x 1 cm pieces up to 4 inch wafers with custom wafer holders
• Autofocus system
• Resolution of ~500nm (6300 system) and ~400nm (Autostep 200)
• Alignment Accuracy of ~250nm using manual alignment
• Alignment Accuracy of ~150nm using automatic alignment
• Positive and negative high resolution resists and processes available
• Automatic leveling and mask aperturing on Autostep 200 system

Established Processes
            GCA 6300 training manual
            GCA Autostep200 training manual

Recipes for projection lithography are developed for flat silicon wafers.  Exposure times and focus offsets may change depending on substrate type and surface topography.  In general, an exposure time and projection lens focus variation is done to determine best focus. Also, for projection lithography using a monochromatic source, a resist post exposure bake (PEB) is needed to wash out standing wave effects in the resist sidewalls.  Contrast enhancement materials (CEMs) are available to increase the process tolerance window and improve resolution.  We also have some experience with RELACS for narrowing trench widths.  Positive and negative resists are available.