PURPOSE: To make it possible to form a pattern and thereafter grow a crystal in a vacuum vessel in succession, by introducing a first gas after the epitaxial growth of a mask base material on the surface of a compound semiconductor, and by performing a process for projecting an electron beam and a process for etching by a second gas in the vacuum vessel in succession.
CONSTITUTION: A buffer layer 11, a clad layer 12, and a guide layer 14 are grown on a substrate 10, in succession. Thereon, as a mask base material, silicon is deposited, and a deposition layer 14a of one to several atoms in film thickness is formed. Further, this wafer 15 is carried into a film formation chamber 31 from which the air is exhausted by a vacuum pump. Then, a high purity oxygen gas 51 of a first gas is introduced into the film formation chamber 31. Continually, after making the pressure of the film formation chamber 31 be 1×10-7Torr or less by an exhaustion, an electron beam 41 is projected on the surface of the wafer 15 carried in an etching chamber 33. Continuously, the electron beam is stopped from projecting, and a chlorine gas 53 of a second gas is introduced into the etching chamber 33 from a nozzle 43.
AKITA KENZO
SUGIMOTO YOSHIMASA
KASAI SHUSUKE
