A method of treating a semiconductor substrate, which comprises the steps of subjecting a surface of the semiconductor substrate to an annealing treatment, performing an etching treatment of the surface of the semiconductor substrate under a condition where the semiconductor substrate is substantially prevented from being etched and a precipitate exposed from the surface of the semiconductor substrate is selectively etched away, and forming a monocrystalline film of a semiconductor material constituting the semiconductor substrate on the surface of the semiconductor substrate.