MANUFACTURE OF ELECTRONIC DEVICE USING LI2B4O7 SINGLE CRYSTAL

摘要

PURPOSE:To enhance adhesion between a crystal and an electrode when an electronic device is to be manufactured using the lift-off method by a method wherein the device is immersed in a surface stabilizing atmosphere after pretreatment is finished. CONSTITUTION:Mirror polishing is performed to one side of a thin plate 1 cut out from a crystal. Then the plate is immersed in hot Trichlene as pretreatment to remove dirt, fats and oils, etc. on the surface, Trichlene is replaced with alcohol, and rotary drying is performed. Then it is immersed in ethyl alcohol mixed with hydrogen fluoride, alcohol is replaced with pure ethyl alcohol, and rotary drying is performed to stabilize the surface. After then, a resist 3 is applied and dried. Then it is immersed in a surface hardening agent, and rotary drying is performed to harden 4 only the surface. Exposure is performed using a reversal mask, exposure is performed, and development is performed using a developer. After then, an Al layer 5 is formed in a vacuum evaporation device holding the temperature as not to rise to 850 deg.C or more. Then it is immersed in acetone or ethyl alcohol, and lifting off is performed.