APPARATUS AND METHOD FOR PHOTOCHEMICAL VAPOR PHASE FORMATION OF THIN FILM

摘要

PURPOSE:To effectively form a thin film having good quality with a small amt. of gaseous raw materials by introducing the gaseous raw materials into a reaction vessel only for the prescribed time correspondent to the time since the gaseous raw materials receive the irradiation of light until active seeds are generated and form the thin film by reacting relatively with a substrate. CONSTITUTION:WF6 having absorption with light and H2 having no absopriton therewith are introduced from respective cylinders 1, 2 by solenoid valves 8, 9 into the reaction vessel 10 only for the prescribed time in the stage for forming the thin W film on are Si substrate 14. The WF6 is introduced from the solenoid valve 9 of the substrate 14 and the H2 from the solenoid valve 8 existing near an irradiation window 12 respectively into the vessel 10. The substrate 14 is kept heated to 400 deg.C by a heater provided to a stage 13 during this time. Laser pulse light is irradiated into the reaction vessel upon turning off of the gate pulses of the respective solenoid valves. The laser irradiation is stopped when the film of W is formed up to a prescribed film thickness. The thin W film formed in such a manner exhibits the high purity and specific resistance equal. to or better than the purity and specific gravity of the thin film formed by the conventional CVD method. The efficient formation of the thin film at a high speed with a small amt. of the gaseous raw materials is thus made possible.