This invention provides a semiconductor film manufacturing method using a new separation technique and applications thereof. The semiconductor film manufacturing method of this invention includes a separation layer forming a step of hetero-epitaxially growing a separation layer (2) on a seed substrate (1), a semiconductor film forming step of forming a semiconductor film (3) on the separation layer (2), and a separation step of separating, by using the separation layer (2), the semiconductor film (3) from a composite member (Ia) formed in the semiconductor film forming step.