MEMS Process Guides
Selecting the right process step is one of the most consequential decisions in MEMS development. These technical guides compare the process options Rogue Valley Microdevices offers side by side, so you can match each step to your device, your materials, and your performance targets.
These guides cover the choices a working MEMS flow actually faces, from oxide and nitride films to metal deposition, photolithography, and silicon etching. Each guide explains how the competing methods work, compares their material and process characteristics, and gives practical guidance on when to choose each one, written from the perspective of a working MEMS foundry. If you would like to discuss your own process, see our MEMS foundry capabilities or contact our team.
Oxide and Nitride Films
Thermal Oxide vs. PECVD Oxide for MEMS
Compare thermally grown silicon dioxide with PECVD deposited oxide across interface quality, film stress, density, and thermal budget, and learn when each oxide is the right choice for a MEMS or silicon photonics process.
Read the guideLPCVD Nitride vs. PECVD Nitride for MEMS
Compare furnace grown LPCVD silicon nitride with low temperature PECVD nitride across residual stress, hydrogen content, conformality, and masking, and see which nitride fits your membrane, passivation, or etch mask needs.
Read the guideThermal Oxide Color Chart
A quick visual reference for estimating the thickness of a thermally grown silicon dioxide film from its interference color, useful at the bench and during process development.
See the chartWhy Wafers Show Dopant Rings After Thermal Oxidation
Understand the concentric color rings that can appear on heavily doped wafers after oxidation: where they come from, why the oxide makes them visible, whether they matter for your device, and how to avoid them.
Read the guideMetal Deposition and Patterning
E-Beam Evaporation vs. Sputter Deposition for MEMS
Compare the two main physical vapor deposition methods for metal films, including adatom energy, step coverage, lift-off compatibility, alloy fidelity, and adhesion, and learn which process suits your contacts, electrodes, mirrors, or bond pads.
Read the guideMetal Lift-Off vs. Metal Etch for MEMS
Compare additive metal lift-off with subtractive metal etch for patterning metal films, including which metals suit each method, resolution, edge quality, and protection of underlying layers.
Read the guidePhotolithography and Resist Coating
Photolithography Methods for MEMS
Compare contact, proximity, and i-line stepper projection lithography across resolution, mask life, overlay, and front to back alignment, and see which method fits each layer of a MEMS device.
Read the guideSpin Coat vs. Spray Coat Photoresist for MEMS
Compare spin and spray photoresist coating, including coverage over deep cavities and trenches, film uniformity, and material efficiency, and learn when each method is the better fit for MEMS topography.
Read the guideSilicon Etching
DRIE Silicon Etch vs. Wet Silicon Etch for MEMS
Compare deep reactive ion etching with wet silicon etching across sidewall profile, aspect ratio, geometry freedom, throughput, and cost, and learn which silicon etch fits your structures.
Read the guideTMAH Silicon Etch vs. KOH Silicon Etch for MEMS
Compare the two main anisotropic wet etchants for bulk micromachining, including CMOS compatibility, etch rate, mask selectivity, and surface finish, to choose the right chemistry for membranes, cavities, and V-grooves.
Read the guideThermal Processing
Thermal Anneals for MEMS
Learn what anneals do, the main ambients from nitrogen to forming gas, the difference between furnace and rapid thermal annealing, and how to choose conditions within your thermal budget.
Read the guideTalk to a MEMS Foundry
Have a device in development or a process you want to outsource? Rogue Valley Microdevices is a pure play MEMS foundry offering wafer services, thin films, photolithography, metal deposition, and silicon etching on 100mm, 150mm, and 200mm substrates. Contact us to discuss your project and find the right process for your device.