Oxford ICP Etcher (PlasmaPro 100 Cobra)

Oxford ICP Etcher (PlasmaPro 100 Cobra) Location Bay 2 Tool Type Dry Etch Manufacturer Oxford Instruments Model PlasmaPro 100 Cobra 300 Description ICP Etches for III-V/ALE Primary Supervisor Tony Bosch (805) 893-3486 bosch@ece.ucsb.edu Secondary Supervisor Bill Millerski Materials InP, GaAs, GaN, Silicon ALE Recipes Dry Etch Recipes

About

The Oxford PlasmaPro 100 Cobra 300 is intended for etching InP-based, GaAs-baased and GaN-based epitaxies, in addition to Atomic Layer Etching (ALE) processes. The system has a load lock, wide temperature range with rapid heating/cooling, Inductively Coupled Plasma (ICP) coil and a capactively coupled substrate HF (13.56MHz) The fixturing is configured for 4" diameter Si wafers and uses a clamp to hold the sample on the RF chuck. Small pieces may be placed on Silicon carrier wafers, with or without mounting adhesive. Helium back-side cooling is used to keep the sample cool during the etch, but pieces do heat up when placed on carriers.

The in-situ laser monitor installed on this system allows for repeatable etches and endpoint detection via continuous optical monitoring of the wafer reflectivity in a user-determined location, through a porthole on the chamber. The system also has an in situ optical emission monitor for plasma spectroscopy, utilized for chamber clean endpoint detection.

Detailed Specifications

• Temperature Range: –150°C to +400°C
• Gases Available: CH₄, H₂, Ar, Cl₂, BCl₃, SF₆, SiCl₄, O₂, N₂
• ICP Power (max): 3000 W
• RF Power (max): 600 W
• He-back-side cooling
• 100mm wafer held down with ceramic clamp., single-load
  • Users may place pieces onto carrier wafer with or without adhesive. Standard recipes use no adhesive.
  • Pieces must be >7mm from edge of carrier to avoid wafer-clamping mechanism.
• Windows-based Cortex software control of process and wafer handling
• Allowed Materials:
  • InP-based epitaxies - qualified and ready
  • GaAs-baased epitaxies - starter recipe is available
  • GaN-based epitaxies - starter recipe is available
  • GaSb-based epitaxies - starter recipe is available
  • Atomic Layer Etching on select materials - starter recipe is available
• Standard masking materials include:
  • SiO₂
  • Si₃N₄
  • photoresist (at << 100°C).

Other materials can be exposed to the chamber only with staff approval.

• Laser monitoring with camera and etch simulation software: Intellemetrics LEP 500
• Optical Emission Spectroscopy (Ocean Optics) for endpoint detection of chamber cleans & etches - integrated into Oxford software

Documentation

• Oxford PlasmaPro Operating Instructions
  • Includes "Travelers" and post-cleaning for each type of standard etch (InP, GaAs, GaN)
• Laser Etch Monitoring procedures
• Online Training Video:
  • Oxford Cobra 300 Training
  • Important: This video is for reference only, and does not give you authorization to use the tool. You must be officially authorized by the supervisor before using this machine.

Recipes

• Oxford PlasmaPro Recipes - Recipes specific to this tool.
• Process Control Data - Calibration etch data for verifying tool performance over time
• All Dry Etching Recipes - use this list to see other options for dry etching various materials.