| 摘要 |
PURPOSE:To prevent the generation of a low electron concentration region in the interface of a growth layer, and to improve quality by washing the inside of a reaction vessel, in which a post epitaxial layer is shaped to the GaAs epitaxial wafer, with an acidic liquid and treating the wafer at a high temperature in hydrogen or an inert gas. CONSTITUTION:An n<-> active layer 12 having 10<15>cm<-3> electron concentration is formed discontinuously through pre-epitaxial growth and an n<+> layer 13 through post epitaxial growth to the low resistance n type GaAs wafer 11 as a substrate preparing an appliance such as a gun diode, and the wafer is used. Extraneous matter in the reaction vessel 49 is dissolved with nitrohydrochloric acid prior to the post epitaxial growth, and washed with pure water, fluoric acid and pure water. The wafer is dried, the vessel 49 is set without mounting the wafer, a gas such as hydrogen refind at high purity is flowed, and the wafer is heated for fourty min at 850 deg.C. The wafer 412 is placed, and post epitaxial growth is conducted at a tmperature such as 600-720 deg.C while using organic gallium and arsine as reaction gases. Accordingly, the electronic concentration, the controllability of the thickness and the reproducibility of the epitaxial layer can be improved, and the scattering, etc. of the threshold value of the gun diode can be removed. |
