Dry Etch Services: DRIE and Plasma Etching at a U.S.-Based MEMS Foundry
Rogue Valley Microdevices provides dry etch services for silicon wafers, MEMS devices, and semiconductor thin films, including DRIE deep reactive ion etching and plasma etching. Our engineers work directly with you to select the right etch chemistry, mask materials, and process conditions for each application.
Because our dry etch tools operate inside a full MEMS foundry environment, you gain production-grade wafer processing that supports both device development and manufacturing, with wet etch, lithography, and thin-film deposition available on the same line. Dry etch can run as a standalone wafer service or as part of a fully integrated device fabrication flow.
Deep Reactive Ion Etching (DRIE) for Silicon MEMS Structures
Deep reactive ion etching (DRIE) enables high-precision silicon etching for MEMS device fabrication. The process forms deep trenches and cavities while maintaining steep sidewalls and tight dimensional control.
Engineers choose DRIE over conventional plasma etching when device geometry demands deep, vertical features: the combination of anisotropy, dimensional accuracy, and run-to-run repeatability makes it the default choice for high-aspect-ratio silicon structures.
Standard DRIE technical specifications:
| Parameter | Capability |
|---|---|
| Aspect Ratio | Standard processing up to 15:1 |
| Etch Depth | 5µm to through-wafer |
| Minimum Feature (CD) | 3µm |
| Sidewall Profile | Vertical profiles maintained at 90 ±1 degrees |
| Uniformity | Depth uniformity within ±5% on deep etches, with controlled feature dimensions from center to edge of 200mm silicon wafers |
DRIE silicon etching enables the three-dimensional microstructures that define MEMS device performance, including:
- Pressure sensor cavities
- Microfluidic channels
- Suspended mechanical structures
- MEMS actuators and resonators
- Optical MEMS components
Plasma Etching for Thin Films and Dielectric Layers
Plasma etching removes material through a controlled combination of reactive gas chemistry and ion bombardment, letting engineers pattern dielectric films while holding tight control of etch rates and feature dimensions. Our plasma dry etch processes support the dielectric films used in MEMS fabrication, including:
- Silicon dioxide (SiO₂)
- Silicon nitride (Si₃N₄)
- Silicon oxynitride
Fluorine-based plasma chemistries provide high selectivity and clean etch profiles when processing dielectric films deposited through PECVD, LPCVD, and thermal oxidation processes.
Etch, Lithography, and Deposition Under One Roof
Plasma dry etching plays a key role after photolithography patterning, where patterned photoresist masks define the areas of material removal. Because thin-film deposition, masking, etch, and metrology all happen in one fab, we can tune each step against the ones around it instead of handing wafers between vendors.
Etch Verification and Process Monitoring
Every etch runs with verification built in. We measure etch depth against target, monitor uniformity across the wafer, and track run-to-run repeatability so results stay consistent from wafer to wafer and lot to lot. Each step is recorded on process travelers, giving you a traceable record of exactly how your wafers were etched.
DRIE or Wet Etch?
DRIE produces vertical, high-aspect-ratio features, while anisotropic silicon wet etching with KOH or TMAH delivers crystal-plane geometry and batch-process economy. Plasma etch can also be combined with wet etch techniques for optimal results during MEMS fabrication. Our DRIE vs. silicon wet etch guide walks through the trade-offs. And when a metal resists etching altogether, our metal lift-off process patterns it additively instead.
Applications for Dry Etch and DRIE
Engineers rely on plasma etch and DRIE processes to shape materials with the accuracy required for advanced microtechnology. Common applications include:
- MEMS pressure sensors
- Accelerometers, gyroscopes, and inertial measurement units (IMUs)
- Microfluidic and biomedical MEMS devices
- RF MEMS switches
- Optical MEMS structures
- Silicon microcavities and trenches
Request a Quote for Dry Etch Services
Send us your device geometry, substrate, and target features, and our process engineers will recommend the right dry etch approach and turn around a practical quote. Request a quote to get started.