| 摘要 |
PURPOSE:To conduct heat treatment excellently, and to improve characteristics by forming protective films onto the surface and back of the compound semiconductor device and turning over and mounting the compound semiconductor to a base, while the surface thereof is particularly mirror-treated. CONSTITUTION:The surface and back of the semi-insulating GaAs substrate 13 into which Si ions are injected 14 are coated with the Si3N4 films 16 with approximately 1,200Angstrom thickness at a low temperature. The ion injecting layer 14 side is placed onto the flat quartz base 17 particularly mirror-treated, and the substrate 13 and the base 17 are fast stuck. The substrate 13 is heated at 600- 950 deg.C by means of an oven 18, and thermally treated in an Ar atmosphere 20. In this constitution, only the back of the substrate 13 is exposed directly to Ar 20, and when As in pin holes reaches fixed pressure GaAs further does not dissociate, an excellent crystal condition is kept and the substrate is thermally treated even when there are the pin holes in Si3N4 because the surface and the base are fast stuck. Accordingly, Si3N4 is thinned, thermal strain is reduced, cracking around a pattern is prevented, and electrical characteristics can be improved. |
