MANUFACTURE OF COMPOUND SEMICONDUCTOR THIN FILM, SOLAR BATTERY USING THE SAME, COMPOSITION DETERMINING METHOD OF COMPOUND SEMICONDUCTOR THIN FILM AND THIN FILM FORMATION DEVICE

摘要

PROBLEM TO BE SOLVED: To easily manufacture a compound semiconductor thin film having a composition suitable for a solar battery by controlling the composition of a compound semiconductor thin film by using that temperature variation speed of a compound semiconductor thin film varies according to the composition of a compound semiconductor thin film in a thin film formation process of groups I, III and VI elements. SOLUTION: A first compound semiconductor thin film 24 is formed by supplying group III element and group IV element on a base 23 formed of a substrate 22 wherein an Mo thin film 21 is formed. Thereafter, a second compound semiconductor thin film 25 is formed by supplying an element comprising a group I element and a group IV element on the thin film 24. Furthermore, a compound semiconductor thin film 26 consisting of group I-III-VI is formed by supplying an element comprising a group VI element on the second compound semiconductor thin film 25. In the process, one temperature lowering speed selected from the base 23 and the compound semiconductor thin film 26 is measured until it is threshold or below, and a compound semiconductor thin film of Cu/group III ratio is 1 or below is formed.