PECVD Films for MEMS and Sensor Devices

PECVD Thin Film Deposition for MEMS and Sensor Devices

Plasma Enhanced Chemical Vapor Deposition (PECVD) enables the deposition of high-quality dielectric thin films at relatively low processing temperatures, making it an essential technology in modern MEMS fabrication and semiconductor manufacturing.

At Rogue Valley Microdevices, our PECVD deposition processes are designed to produce uniform dielectric films on silicon wafers while maintaining compatibility with temperature-sensitive device structures and complex process flows.

PECVD thin films are widely used for device passivation, dielectric insulation, and protective coatings in microfabricated devices. By combining controlled plasma-assisted deposition with flexible wafer processing capabilities, we support engineers developing MEMS sensors, semiconductor components, and advanced microdevices.

Advantages of Our PECVD Thin Films

PECVD deposition offers several advantages for semiconductor and MEMS manufacturing processes:

• Low-temperature thin film deposition
• Reliable dielectric insulation layers
• Consistent wafer-level film uniformity
• Strong adhesion to silicon wafers and other substrates
• Controlled film stress for device integration
• Good conformal coverage across microstructures

These characteristics make PECVD thin films particularly useful in process flows where thermal budgets are limited or where films must be deposited over existing device layers.

PECVD Film Applications

• MEMS pressure sensors
• Accelerometers and inertial sensing devices
• Microfluidic and lab-on-chip devices
• Optical MEMS components
• Device passivation
• Dielectric isolation layers

Because PECVD films can be deposited at moderate temperatures, they are especially valuable in multi-layer device fabrication processes where maintaining device integrity is critical.

PECVD Silicon Nitride (SiN)

PECVD silicon nitride films are frequently used for surface passivation and dielectric protection in MEMS and semiconductor devices. These films help protect device structures from environmental exposure while maintaining reliable electrical isolation.

Typical uses include:

• Passivation layers for semiconductor devices
• Moisture barrier coatings
• Dielectric insulation layers
• Protective coatings for MEMS devices

The following standard PECVD silicon nitride films can be deposited in thicknesses up to 2 µm:

• PECVD Nitride
• Low-Temperature PECVD Nitride
• Low-Stress PECVD Nitride (<250 MPa tensile)
• Low-Temperature Low-Stress PECVD Nitride

PECVD Silicon Dioxide (SiO₂)

PECVD silicon dioxide is commonly deposited as an electrical insulation layer or dielectric isolation film in microfabricated devices. PECVD oxide films offer consistent coverage and reliable electrical properties across the wafer.

Typical applications include:

• Dielectric isolation layers
• Interlayer insulation
• MEMS device passivation

The following standard PECVD oxide films can be deposited in thicknesses up to 5 µm:

• PECVD Oxide
• Low-Temperature PECVD Oxide

PECVD Silicon Oxynitride (SiON)

PECVD silicon oxynitride (SiON) thin films provide a versatile dielectric material that combines the properties of silicon dioxide and silicon nitride. By adjusting the oxygen-to-nitrogen ratio during deposition, PECVD silicon oxynitride films can be engineered with a wide range of electrical, optical, and mechanical properties to support advanced MEMS devices and sensor structures. Common applications include:

• Optical MEMS and photonic devices
• Dielectric isolation layers
• Device passivation layers
• Optical coatings and waveguide structures
• Thin films requiring controlled refractive index

Our PECVD SiON films can be deposited up to 4 µm in thickness, with customized refractive index or film stress tailored to your process requirements.

Available options include:

• Targeted Refractive Index SiON
• Targeted Film Stress SiON
• Low-Temperature SiON (<350 °C)