DRIE: Bosch & Cryo ICP-RIE for Silicon

DRIE Instrument Type Etching Techniques Bosch, Cryogenic etch of silicon Staff Manager Nathan S. Lee Staff Email nathslee@caltech.edu Staff Phone 626-395-1319 Reserve time on LabRunr Request training by email Lab Location B235 Steele Lab Phone 626-395-1532 Manufacturer Oxford Instruments Model {{{Model}}}

Description

The MEMS / Bosch / Cryo Inductively Coupled Plasma Reactive Ion Etch (ICP-RIE) is is an Oxford Instruments Plasma Technology Plasmalab System 100 ICP-RIE 380 system that is optimized for silicon etching. This system is configured for deep reactive ion etching (DRIE) via the Bosch process, allowing silicon etching with C₄F₈ and SF₆ gases. Close-coupled gas pods are included in this system for fast Bosch switching; this allows the etching of bulk silicon for MEMS applications with etch rates of approximately 10-25 micrometers/minute. The silicon ICP-RIE has a variable temperature stage (-150 to 400 °C) to permit cryogenic etching of silicon with SF₆ and O₂ if needed. This system supports wafer sizes up to 6 inches, and provides accurate deep etching capabilities for silicon only.

Applications

• Deep silicon etch using Bosch process
• Cryogenic etch of silicon
• pseudo-Bosch of silicon

Allowed material in DRIE

• Si, Si_xN_y, SiO₂, Ge
• PMMA/ZEP/SPR/AZ/maN resists, SiO_x/Al₂O₃ hard masks
• Buried/backside metal ok if never exposed (not an etch stop)

DRIE Gas List

• SF₆
• C₄F₈
• O₂
• Ar
• N₂

Resources

SOPs & Troubleshooting

• SOP Type (Short Version | Long Version)
• Etcher toxic gas handling SOP
• Power Up Oxford ICP-RIE SOP
• Gas Status Board SOP
• Troubleshooting Guide

Process Documents

• Process Standards
• Silicon Waveguide Etch
• Silicon Nitride etch
• Hard Mask Oxide Etch

Manufacturer Manuals

• Oxford Plasmalab System 100 DRIE Manual
• Edwards QDP 80 dry vacuum pump Manual

Specifications

Manufacturer Specifications

• Manufacturuer Data Sheet

Mode 1 Specifications

• Voltage Range: 0.5 to 30.0 kV
• Aperture Sizes: 10 mm, 15 mm, 20 mmm, 30 mm
• etc.

Mode 2 Specifications

• Voltage Range: 5.0 to 30.0 kV
• Current Range: 10 pA - 20 nA
• etc.