Indium Phosphide Substrate Manufacturing Method and Epitaxial Wafer Manufacturing Method

Abstract

The present invention affords methods of manufacturing InP substrates, methods of manufacturing epitaxial wafers, InP substrates, and epitaxial wafers whereby deterioration of the electrical characteristics can be kept under control, and at the same time, deterioration of the PL characteristics can be kept under control. An InP substrate manufacturing method of the present invention is provided with the following steps. An InP substrate is prepared (Steps S 1 through S 3 ). The InP substrate is washed with sulfuric acid/hydrogen peroxide (Step S 5 ). After the step of washing with sulfuric acid/hydrogen peroxide (Step S 5 ), the InP substrate is washed with phosphoric acid (Step S 6 ).

What is claimed is: 
     
         1 . An indium phosphide substrate manufacturing method comprising:
 a step of preparing an indium phosphide substrate;   a step of washing the indium phosphide substrate with sulfuric acid/hydrogen peroxide; and   a step, following said step of washing with sulfuric acid/hydrogen peroxide, of washing the indium phosphide substrate with phosphoric acid.   
     
     
         2 . The indium phosphide substrate manufacturing method set forth in  claim 1 , wherein in said step of washing with phosphoric acid, a aqueous phosphoric acid solution having a concentration of from 1% to 30%, inclusive, is utilized. 
     
     
         3 . The indium phosphide substrate manufacturing method set forth in  claim 1 , wherein in said preparation step an indium phosphide substrate containing a dopant consisting of at least one substance selected from the group composed of iron, sulfur, tin, and zinc is prepared. 
     
     
         4 . An epitaxial wafer manufacturing method comprising:
 a step of manufacturing an indium phosphide substrate according to the indium phosphide substrate manufacturing method set forth in any one of  claim 1 ; and   a step of forming an epitaxial layer onto the indium phosphide substrate.