Oxford RIE

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About

Oxford PlasmaPro 80 RIE tool in Etch Bay

Films / Materials: This is an Oxford Instruments PlasmaPro 80 reactive ion etcher (RIE) optimized for etching dielectric materials such as SiO₂, Si₃N₄, and Si, with good anisotropy and control. It is primarily used for etching dielectrics in micro- and nanofabrication processes.

Hardware: Parallel-plate capacitively-coupled RF plasma system (13.56 MHz). Open-load design for fast loading/unloading of samples. No load lock; direct chamber access. Electrode/table temperature controlled at 20°C (ambient/chilled). Includes optical endpoint detection (Horiba Jobin Yvon LEM G50) for precise process stop.

Gases:

  • Ar (argon – physical sputtering/milling component)
  • O₂ (oxygen – for ashing, oxidation, or enhancing etch rates)
  • CF₄ (tetrafluoromethane – fluorine-based etching of SiO₂/Si₃N₄)
  • CHF₃ (trifluoromethane – for selective SiO₂ etching, polymer sidewall passivation)
  • SF₆ (sulfur hexafluoride – high-rate isotropic/fluorine etching of Si/SiO₂)

Etch Properties:

  • Primarily anisotropic etching of dielectrics via ion bombardment and chemical reactions.
  • Suitable for shallow to moderate depth etches (avoid deep polymer etching >1 µm due to restrictions).
  • High selectivity possible depending on gas mix and power (e.g., SiO₂ over Si with CHF₃/O₂).
  • Excellent process control for uniformity across up to 200 mm substrates.

Applications: Etching of dielectric layers (e.g., oxide/nitride masks, passivation removal, via openings), resist descum, surface cleaning/activation. Not for exposed metals (except Cr) or deep polymer etches; polymer may be used as a mask only.

Usage: Load sample directly (pieces to 200 mm wafers), select/load recipe, set time/power based on calibrated etch rates. Use endpoint detection for timed or auto-stop processes. Monitor particles and uniformity post-etch.

Detailed Specifications

  • Model: PlasmaPro 80 reactive ion etcher
  • Location: Etch Bay 1
  • Substrate size: Up to 8 (200 mm) wafers (pieces/smaller possible; open loading)
  • RF Power: Table RF power (max) 300 W (13.56 MHz)
  • Table temperature: 20°C (chilled/controlled) / (max) 80°C
  • Gases:
    • CHF₃ (max) 100 sccm
    • Ar (max) 100 sccm
    • O₂ (max) 50 sccm
    • CF₄ (max) 50 sccm
    • SF₆ (max) 100 sccm
  • Features: Optical endpoint detection (Horiba Jobin Yvon LEM G50), open-load design for fast access, excellent etch uniformity and rate control

Restrictions and Materials Allowed

Restrictions Materials Allowed
  • No exposed metals except Cr
  • No deep polymer etching (> 1 µm)
  • Polymers allowed only as masks
  • Not intended for metal etching
  • Avoid uncalibrated deep or high-aspect-ratio processes
  • SiO₂
  • Si₃N₄
  • Si
  • Oxide masks
  • Nitride masks
  • Passivation removal
  • Via openings
  • Resist descum
  • Surface cleaning and activation
  • Chromium (Cr) as exposed metal

Dry Etcher Comparison

Use this table to help choose the right etching tool for your process.

Feature Oxford RIE (this tool) Oxford DRIE Oxford DRIE-ALE Oxford III-V XeF2 Etcher
Model PlasmaPro 80 RIE Oxford System 100 DRIE Oxford DRIE + ALE PlasmaPro 100 Cobra Custom built (Armani group)
Location Etch Bay 1 Etch Bay 1 Etch Bay 1 Etch Bay 1 Deposition Bay 1
Substrate Size Up to 200 mm (8") Up to 4" clamp; 2", 3", 4", 6", 8" possible TBD (commissioning) Up to 4" clamp; 2", 3", 4", 6", 8" possible Up to 6"
Etch Type RIE (capacitively coupled) DRIE / Bosch (ICP) DRIE + Atomic Layer Etch ICP-RIE (cryo capable) Isotropic chemical etch
Table RF Power 300 W max 300 W max TBD 1500 W max N/A
ICP Power None (RIE only) 3000 W max TBD 1500 W max N/A
Table Temperature 20°C 20°C TBD -120°C to 200°C 20°C
Gases Ar, O₂, CF₄, CHF₃, SF₆ Ar, O₂, CF₄, CHF₃, SF₆, C₄F₈ TBD Ar, O₂, SF₆, CH₄, H₂, Cl₂, BCl₃, SiCl₄ XeF₂ (crystal source)
Allowed Materials Si, SiO₂, Si₃N₄, oxide/nitride masks, Cr Si, SiO₂, SiN, Parylene, Polyimide, LiNbO₃, BCB TBD InP, InAs, GaN, AlGaAs, GaAs, InGaAsP, ITO, Si, SiC, MoS₂, WSe, Graphene Si only
Disallowed No metals except Cr; no deep polymer >1 µm No exposed metals except Cr TBD No metals except Cr; no deep polymer >1 µm None listed
Endpoint Detection ✓ Optical (LEM G50) ✓ Optical TBD ✓ Optical (LEM G50)
Best For Dielectric etching, passivation removal, via openings, resist descum Deep Si etching, high-aspect-ratio structures, Bosch process Precise atomic-layer-level etch control III-V semiconductors, exotic/compound materials, cryo etching Fast isotropic Si etching, high selectivity
Status ✓ Operational ✓ Operational ⚠ Being commissioned ✓ Operational ✓ Operational
SOP SOP SOP TBD SOP SOP

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