PURPOSE: To enable semiconductor micro-structures to be accurately formed as small in size as required at a required interval by a method wherein a porous anodic oxide film is used as a mask.

CONSTITUTION: The surface of an Al film 2 formed on an InP substrate 1 is oxidized by an anodic oxidation method for the formation of a porous anodic oxide film 3. Then, a window 4 is provided to the Al film 2 so deep as to reach the InP substrate 1 through an argon sputtering method using the porous anodic oxide film 3 as a mask. Then, a GaInAsP layer 5 is selectively grown using the Al film 2 and the porous anodic oxide film 3 as a mask through an organic metal molecular beam epitaxy method. After a selective growth process is carried out, the mask composed of the Al film 2 and the porous anodic oxide film 3 is removed, and an InP layer 6 is formed to bury the GaInAsP layer 5 in it, whereby a quantum well box of GaInAsP is formed in InP. By this setup, semiconductor micro-structures below 10nm in size and high in uniformity can be manufactured high in controllability.