| 摘要 |
PURPOSE:To prevent the generation of variation in electrical characteristics within the substrate surface, by a method wherein the mirror surface of an another compound substrate containing the same element as a high vapor-pressure element contained in a compound semiconductor substrate to be heat-treated is brought into opposition contact with the ion-implantation- finished surface of the latter substrate where a dielectric protection film has been formed, which are then heat-treated at the temperature for activating the implanted atoms. CONSTITUTION:In a semi-insulation GaAs substrate 1, an n-layer implantation pattern serving as the operating layer of a FET is formed out of resist, and 28Si<+> is implanted at an acceleration energy of 180KeV and an implantation amount of 1.5X10<12>cm<-2>, thus forming an n-layer 4. Similarly, 28Si<+> is implanted under source 6 and drain 7 electrodes at an acceleration energy of 50KeV an an implantation amount of 2.0X10<13>cm<-2>, thus forming an n<+> layer 5. Next, over the substrate surface finished in ion implantation, a uniform Si nitride film 2 of 1,300Angstrom is formed by plasma CVD out of the mixed gas of SiH4 with NH3 at a temperature of 270-280 deg.C. Then, when heat treatment is carried out, in the situation that the mirror surface of a GaAs substrate 3 is in close contact with the surface of the substrate 1 to be heat-treated where the Si nitride film has been formed, at the temperature for activating the ion implantation atoms, the substrate is recovered from damage generated by ion implantation, and the activation that the implanted atoms are introduced to lattice points is performed. |
