Methods of fabricating integrated circuits for high voltages

Bipolar integrated circuits with breakdown voltages from 200 to 250 V were produced using three techniques. Aluminum implantation with subsequent diffusion was employed as a fast insulation method. Heavily phosphorous-doped V grooves allowing a low-ohmic collector contact were studied. Polycrystalline silicon doped with oxygen, used as a passivation layer shows excellent results in suppressing parasitic MOS-channels.