HOLE FORMING METHOD OF GA-AS SUBSTRATE USING WET ETCHING

摘要

The via hole of GaAs substrate for MMIC and digital integrated circuit is formed by the following steps: (a) polishing the GaAs substrate with sand paper and alumina powder of 0.05-1μm thickness; (b) etching the substrate using the NH4OH / H2O2 / H2O solution for mirror face polishing of rough surface; (c) sticking the substrate to the micro slide glass using Az1375 photoresist for preventing the cracking of substrate; (d) etching the substrate at temperature of 60-70 deg.C using the etching solution containing the 80ml (85W/O) H3PO4 : 80ml (30W/O) H2O2 : 30ml H2O ratio.