METHOD AND APPARATUS FOR FORMING PROTECTIVE FILM OF CLEAN SUBSTRATE IN FORMING MOLECULAR BEAM EPITAXIALLY GROWN LAYER

摘要

PURPOSE:To prevent a growing chamber from contaminating and a raw material to be deposited from early consuming by generating ionized particles in a substrate pretreating chamber, heating the substrate while exposing with the particles, cleaning to remove impurity substances, and then lowering the temperature of the substrate to adhere and accumulate component elements of the particles on the cleaned surface of the substrate to form a protective film. CONSTITUTION:Etched substrates are fusion-bonded to a substrate holder with a low melting point metal, and the substrates 7a-7f are contained in a substrate pretreating chamber formed of vacuum vessels. Then, an evaporation source is heated in the chamber to evaporate the raw material to be evaporated, the substance is heated to ionize the substance, and ionized particles 6 are irradiated toward the substrates. Thus, the substrates are heated at approx. 650 deg.C while exposing with the particles 6. The substrates are effectively cleaned by heating the substrates. Then, after the substrates are completely cleaned, the heating temperature of the substrates is lowered in the chamber. The particles are adhered and accumulated on the cleaned substrates by the temperature drop to form an amorphous protective film. When the protective film is adhered by 1mum or larger, the substrate is moved to a crystal growing chamber.