The wet chemical etching of glass and silicon substrates is one of the core competencies of Micronit. Additionally, Micronit GmbH offers etchings of various metals as well, such as Au, Cr, Cu, Ni, Ti etc. and the etching of non-conductors such as oxide and nitride.
Wet etching is a chemical etching process using a fluidic etchant. The advantage of the wet etching process for you as our customer is that it can be applied in batches therefore increasing the cost effectiveness.
Wet etching of glass is an isotropic etching technique done with hydro fluidic acid (HF). Isotropic means that the width of the structure on both sides is increased by the size of the etching depth. The corners are rounded off. The surface of the etch structures are corresponding to the glass used very smooth.
Anisotrophic etching using alkali hydroxides such as KOH, NaOH or amine-containing solutions such as TMAH etches silicon along the crystal plane. KOH is the most popular, having been in industrial use for decades. Depending on the temperature and concentration, different etch rates and surface roughness can be created. TMAH is used when oxide is to be maintained. The masking is done using a nitride deposition, which was lithogrphically structured before. Special KOH holders are used here.