The Georgia Tech STS Pegasus ICP is a deep reactive ion etcher (DRIE) with a dual plasma source design. It is designed to etch silicon through a Bosch Process. The process allows the sample to have a more uniform, anisotropic etch on 4" wafers. The STS Pegasus ICP is unique and provides users with high etch rates, excellent uniformity, and results in a highly concentrated and uniformed distribution of radicals.

Function

• Silicon Trench Etching (Bosch process)
• First Pegasus installed in US university

Materials etched and acceptable masks

• Etched: Si, poly-Si, α-Si
• Masks: Photoresist, Si3N4 , SiO2

Component Specifications

• 5000W 13.56MHz MKS – Coil
• 500W 13.56MHz ENI -- Platen
• 300W 380kHz AE LF-5
• Backside helium cooling with electrostatic chuck

Gases 

• C4F8 , SF6 , O2 , Ar

Substrate size

• small pieces – one 100mm wafer or 150mm capability

Process Pressure 

• 2-80mT

Temperatures

• Platen -20°C to 40°C, Walls 120°C, Lid 120°C

Vendor Specified Capabilities with 10% exposed Si (Width : Trench Depth)

• 0.5µm : 30µm SOI (LF platen)
• 0.2µm : 10µm SOI (LF platen)
• 3µm : 100µm (HF platen)
• 2µm : 60µm (HF platen)