FORMATION OF THIN FILM

摘要

PURPOSE:To stably form a uniform thin film on the surface of a substrate in the vacuum vessel of a plasma CVD device in which gaseous starting material is introduced into the vessel and irradiated with microwaves to form a thin film on the surface of the substrate, by placing an electrode cover the substrate at a prescribed interval. CONSTITUTION:An Si substrate 6 in a vacuum vessel 1 is heated to 900 deg.C and gaseous H2 is mixed with gaseous CH4 in 100:1 pressure ratio and introduced into the vessel 1 from the gas introducing hole 4 so that the pressure of the gaseous mixture is regulated to 10-50Torr. Microwaves 2 having 2.54GHz frequency are then introduced into the vessel 1 from a waveguide 3 to convert the gaseous mixture into plasma and a thin diamond film is formed on the surface of the substrate 6 by the decomposition of the gaseous CH4. At this time, an electrode 7 made of a wire net is placed over the substrate 6. The plasmatic particles are accelerated by the electrode toward the substrate to form a homogeneous thin diamond film and the microwaves are intercepted by the electrode to prevent the damage of a heater for heating the substrate.