Etching

DRIE etching

Deep Reactive Ion Etching (DRIE or plasma etching) is a unique technique to create deep, high density and high aspect ratio structures in glass (fused silica) and silicon substrates. Micronit is one of the few companies able to use the DRIE method in glass substrates.

Etching with steep side walls (anisotropic etching) as well as with rounded walls (isotropic etching) in substrates is possible, with depths varying between 1 µm cavities and complete wafer-through holes.

Capabilities of Micronit in DRIE etching are as follows (based on a silicon substrate):

Aspect ratio 1:15;
Wafer-through etching;
Variable inclination of the channel walls;
DRIE on SOI wafers

Wet etching

Micronit applies wet etching (HF etching) techniques to create channel structures in glass and silicon. HF is a hydrofluoric acid, commonly used for cleaning metal and etching glass. For the HF etching technique we use masks which make the absolute positioning of the structures accurate within one micrometer. By using a mask, the amount of channels, reservoirs, mixing and reaction chambers is irrelevant for the costs of the process.