Single crystalline diamond and producing method thereof

Abstract

The object of the present invention is to obtain a high quality single crystalline diamond that has less distortion and large area suitable for semiconductor device substrates or an optical component material. The present invention is a single crystalline diamond produced by chemical vapor deposition, wherein, when a linear polarized light which is composed of two linear polarized lights perpendicular to each other is introduced into one main face of the single crystalline diamond, a maximum value of a retardation between the two linear polarized lights perpendicular to each other which come out from an opposite main face is not more than 50 μm at maximum per a thickness of 100 μm across an entire of the single crystalline diamond, and also a method for producing the diamond.

1 - 13 . (canceled) 
   
   
       14 . A semiconductor substrate which utilizes a single crystalline diamond produced by chemical vapor deposition, wherein
 when a linear polarized light which is composed of two linear polarized lights perpendicular to each other is introduced into one main face of the single crystalline diamond, a maximum value of a retardation between the two linear polarized lights perpendicular to each other which come out from an opposite main face is not more than 50 nm per a crystal thickness of 100 μm across an entire of the single crystalline diamond.   
   
   
       15 . A diamond optical component which is obtained by processing a single crystalline diamond produced by chemical vapor deposition, wherein
 when a linear polarized light which is composed of two linear polarized lights perpendicular to each other is introduced into one main face of the single crystalline diamond, a maximum value of a retardation between the two linear polarized lights perpendicular to each other which come out from an opposite main face is not more than 50 nm per a crystal thickness of 100 μm across an entire of the single crystalline diamond.   
   
   
       16 . A method for producing a single crystalline diamond comprising the steps of:
 mechanically polishing a main face and a side face of a single crystalline diamond substrate as a seed;   etching the main face and the side face by reactive ion etching;   newly growing a single crystalline diamond layer thereon by chemical vapor deposition; and   separating the single crystalline diamond layer newly grown by chemical vapor deposition from the single crystalline diamond substrate as a seed.   
   
   
       17 . A method for producing a single crystalline diamond according to  claim 16 , wherein an inclination of the side face of the single crystalline diamond substrate after the mechanically polishing is within a range of not less than 82 degree and not more than 98 degree with respect to the main face. 
   
   
       18 . A method for producing a single crystalline diamond according to  claim 16 , wherein thicknesses of the main face and the side face of the single crystalline diamond substrate as a seed to be etched are not less than 0.5 μm and less than 400 μm.