LED Wet Etch Protection
During LED fabrication, the wafer is exposed to several acid and/or alkaline etch chemistries depending on the fabrication process flow. For example:
- Silicon-based cavity submounts are fabricated by etching silicon in alkaline etchant solutions.
- GaN or subsequent CVD passivation layers are etched or patterned using alkaline- or acid-based chemistries.
During these processes, the wafer and the sensitive features on the wafer must be protected from the harsh chemicals used for etching.
Brewer Science offers both blanket and photosensitive coatings for acid- or alkaline-based etch protection purposes.