Brewer Science^® protective coating processes enable the development of MEMS, sensors, and compound semiconductor devices and provide break through solutions that can remove customers’ current and future roadblocks. Our protective coating systems use processes and equipment that would normally be found in photolithography tracks, and do not require special equipment for application. Depending upon your current bulk micromachining method, ProTEK^® coating systems can lower capital investment, lower cost, lower risk and provide higher throughput.

Our spin-applied protective coatings are temporary or permanent materials that prevent fragile structures from being damaged during bulk and surface micromachining applications. They can be used to prevent wafer damage (protective coatings), prevent deposition of materials in specific wafer locations (lift-off coatings), or improve lithography over high topography (planarizing coatings).

All Brewer Science^® protective coatings allow micromachining to take place closer to packaging, which simplifies the processes and improves device yield. The low-temperature processing of these films allows them to be coated over CMOS structures, unlike SiO2 or SiN layers.

Protective coatings also allow the release of membranes and proof masks and the creation of through-silicon vias (TSVs) as a last step before packaging. This capability improves the process and device yield.

Alkaline Processes

Brewer Science^® ProTEK^® films are available as either blanket films or as photosensitive etch masks. For alkaline processes, the ProTEK^® B3 and ProTEK^® PSB films provide blanket or etch mask protection for up to 24 hours in hot concentrated KOH or TMAH solutions.

Blanket Coatings

Blanket coatings protect delicate structures from the harsh environment of micromachining. The ProTEK^® family of coatings enables micromachining processes to take place later in the device manufacturing process flow. CMOS type processes and MEMS structures can be created prior to releasing a device’s proof mass, cantilevers, or air bridges.

Photosensitive Coatings

Photosensitive coatings act as an etch mask during micromachining. ProTEK^® PSB coating replaces a SiN etch mask during a KOH wet-etching process, or can be used as an enhancement layer for the PECVD SiN mask where cracking and pinholes are frequently an issue. The ProTEK^® PSB coating is spin applied, goes on at a lower temperature, and can be removed by dry etching or by wet cleaning processes such as those using a Piranha solution.

Acid Processes

ProTEK^® A materials for acid etching allow the creation of microfluidic channels or the release of proof masses as a last step before packaging, which can improve the process and the device yield. ProTEK^® A materials provide protection for the substrate from either hydrofluoric acid (49% HF) or buffered oxide etchant (BOE) etch solutions.