Nitride-type semiconductor element and process for production thereof

Abstract

A nitride-based semiconductor device includes a p-type Al d Ga e N layer 25 whose growing plane is an m-plane and an electrode 30 provided on the p-type Al d Ga e N layer 25 . The Al d Ga e N layer 25 includes a p-Al d Ga e N contact layer 26 that is made of an Al x Ga y In z N (x+y+z=1, x≧0, y>0, z≧0) semiconductor, which has a thickness of not less than 26 nm and not more than 60 nm. The p-Al d Ga e N contact layer 26 includes a body region 26 A which contains Mg of not less than 4×10 19 cm −3 and not more than 2×10 20 cm −3 and a high concentration region 26 B which is in contact with the electrode 30 and which has a Mg concentration of not less than 1×10 21 cm −3 .

1 .- 15 . (canceled) 
     
     
         16 . A method for fabricating a nitride-based semiconductor light-emitting device, comprising the steps of:
 (a) providing a substrate;   (b) forming on the substrate a nitride-based semiconductor multilayer structure including a p-type semiconductor region, a growing plane of the p-type semiconductor region being an m-plane; and   (c) forming an electrode on the growing plane of the p-type semiconductor region of the semiconductor multilayer structure,   wherein step (b) includes a step (b1) of forming a contact layer as part of the p-type semiconductor region, the contact layer being made of an Al x Ga y In z N (x+y+z=1, x≧0, y>0, z≧0) semiconductor, the contact layer having a thickness of not less than 26 nm and not more than 60 nm, and   step (b1) includes
 forming a body layer which contains Mg of not less than 4×10 19  cm −3  and not more than 2×10 20  cm −3 , and 
 forming a high-concentration layer which has a Mg concentration of not less than 1×10 21  cm −3  and has a thickness of not less than 0.5 nanometers and not more than 5 nanometers so as to deposit magnesium on the surface thereof, and 
   step (c) includes forming the electrode so as to be in contact with the high-concentration layer.   
     
     
         17 . The method of  claim 16 , wherein the body layer contains Mg of not less than 4×10 19  cm −3  and not more than 1×10 20  cm −3 . 
     
     
         18 . The method of  claim 16 , wherein step (c) includes forming the electrode on the high-concentration layer, the electrode having a first layer which contains at least any one of Mg, Zn, and Ag. 
     
     
         19 . The method of  claim 18 , wherein step (c) includes forming the electrode such that the electrode has the first layer and a second layer provided on the first layer, the second layer being made of at least one metal selected from a group consisting of Ag, Pt, Mo, and Pd. 
     
     
         20 . The method of  claim 16 , further comprising the step of performing a heat treatment after step (c).