| 摘要 |
PURPOSE:To enhance the safety and workability by preventing irregular evaporation of component atoms of a compound semiconductor substrate, thereby preventing the irregular electric characteristics in the substrate. CONSTITUTION:A dielectric protective film 2 is formed on the surface of a GaAs substrate 1 of a compound semiconductor substrate, and the substrate 1 is heat treated in the state that another two GaAs substrates 3, 4 are disposed at upper and lower sides of the substrate 1. The heat treatment is an annealing to form the interior of the crystal of the substrate homogeneous to heat at the temperature range of 700-1,200 deg.C of the temperature for starting diffusion in the impurity atoms and vacant lattice to the melting point of the crystal for 1- 40hr. The films 2 for suppressing the evaporation of partial component elements of high vapor pressure to coat the front and back surfaces of the substrate 1 is contacted with the substrates 3, 4. Thus, the temperature distortion of the protective film decreases at the temperature rising and falling times, and the possibility of breakage of the protective film decreases. Further, since the evaporation source is the solid GaAs substrate, its handling is simple, and the workability and the safety are improved. |
