Rogue Valley Microdevices provides precision wet etch services for MEMS fabrication and silicon wafer processing. Using chemistries such as KOH, TMAH, and buffered oxide etchants (BOE), our engineers create cavities, remove thin films, and define device structures with high selectivity and excellent surface quality. Silicon wet etching relies on controlled chemical reactions to remove material exactly where your design requires it. Every wet etch step runs in-house at our U.S.-based MEMS foundry in Medford, Oregon, on the same line as the photolithography, deposition, and dry etch processes that complete your fabrication flow. Whether you need a single anisotropic silicon etch on customer-supplied wafers or a fully integrated device process, our team works as an extension of your engineering group, with transparency into every process decision. All work is U.S.-based and ITAR-registered. Silicon Wet Etching Capabilities Wet etching is fully integrated with our MEMS foundry capabilities, so etch steps drop cleanly into complete device process flows: - KOH (potassium hydroxide): Crystalline silicon (anisotropic). Masking Strategy: LPCVD silicon nitride. Typical MEMS Applications: Deep cavities, V-grooves, angled sidewalls, suspended membranes - TMAH (tetramethylammonium hydroxide): Crystalline silicon (anisotropic). Masking Strategy: Thermal silicon dioxide. Typical MEMS Applications: Cavities, trenches, and diaphragms with critical layers preserved - BOE (buffered oxide etch): Silicon dioxide layers. Masking Strategy: Patterned photoresist. Typical MEMS Applications: Contact windows, sacrificial layer removal, dielectric patterning - Metal wet etch: Gold (Au), chromium (Cr), aluminum (Al). Masking Strategy: Patterned photoresist. Typical MEMS Applications: Conductive pathways, electrodes, bonding pads Our team works closely with you to optimize etch chemistry, process conditions, and wafer handling for reliable MEMS device performance. From Development to Volume Production Because wet etch runs inside an active MEMS production fab, the process that etches your first prototype wafers is the same one that supports volume manufacturing. That means no technology transfer, no re-qualification surprises, and no translation loss between development and production.
