Method for Forming Semiconductor Layer

A method for forming a semiconductor layer, the method comprising:

• (i) crystal-growing, on a substrate, a first semiconductor layer, the first semiconductor layer having a lattice constant in a planar direction of a surface of the substrate which is different from a lattice constant of the substrate in the planar direction of the surface of the substrate;
• (ii) crystal-growing a second semiconductor layer on the first semiconductor layer;
• (iii) selectively dissolving the second semiconductor layer to form a recess at a dislocation portion of the second semiconductor layer, the recess reaching the first semiconductor layer;
• (iv) oxidizing the first semiconductor layer through the recess and forming an insulating film covering a lower surface of the second semiconductor layer;
• and
• (v) crystal-regrowing the second semiconductor layer after forming the insulating film.