Dry etching

Process name Sample size Characteristics Relevant equipment
SiO2 etching Part 5x5mm to wafer 6 inches RIE etching.
Gases used : CHF3 + O2.
Etching rate: ~ 500A/min,
Cr mask 800A,
selectivty/Cr ~ infinite,
profile ~90°
Reactive Ion Etching
Isotropic Si etching Part 5x5mm to wafer 4 inches DRIE ICP etching.
Gases used : SF6.
Etching rate ~ 6µm/min.
Masks : Cr, SiO2, S1813, SPR220 3.0.
Selectivity ~ infinite for all masks.
Deep Reactive Ion Etching
Anisotropic Si etching Part 5x5mm to wafer 4 inches DRIE ICP etching by Bosch process.
Gases used: SF6, C4F8, O2.
Masks : Cr, S1813, SPR220 3.0 and 7.0.
Variable etching rate ~ 1µm/min.
Selectivity/Cr ~ infinite, selectivity/resin variable ~1:40.
Etching profile ~90°.
Possible aspect ratio : 1:30.
Deep Reactive Ion Etching