Oxford ICP Etcher (PlasmaPro 100 Cobra)

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Oxford ICP Etcher (PlasmaPro 100 Cobra)
OxfordPlasmaPro.jpg
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

Recipes

Process Control Data

Click above for calibration etch data for verifying tool performance over time.

Std InP Ridge Etch: Cl2/CH4/H2/60°C

Calibration / Process testing data taken using the "InP Ridge Etch" process: Cl2/CH4/H2 @ 60°C, 1cm piece with ~50% SiO2 hardmask.

GaN Etch (Cl2/BCl3/Ar/200°C)

Recipe: Std GaN Etch - BCl3/Cl2/Ar - 200C (Public), on 1cm x 1cm ~1.2µm deep GaN etch with Cl2/BCl3/Ar at 200°C. Sapphire substrate with SiO2 mask for GaN.