| 摘要 |
PURPOSE:To compensate omission of As atoms and to obtain a p-type GaAs wafer having no warpage, no crack from a bit part, and no formation of a high resistance layer by previously increasing arsenic concentration of a surface, and then mirror-finishing the surface of the wafer by etching and polishing. CONSTITUTION:Metal As 4 is sealed in the other end in a quartz ampule 5. The As 4 is heated by an As pressure control heater 7, evaporated, and invaded thereinto from the surface of the wafer 1. The pressure of As gas is controlled by the temperature of the heater 7 and an As diffusion barrier 8. The wafer 1 is annealed at 800-1200 deg.C for 10-50 hours by an annealing heater 6 even under such As gas pressure to implant predetermined As atoms on the wafer. Then, the wafer 1 is removed from the ampule 5, the surface is lapped, etched, polished to be mirror-finished. Thus, excessive As layer on the wafer is removed. |
