P-type Group III nitride semiconductor and production method thereof
An object of the present invention is to provide a method for producing a p-type Group III nitride semiconductor which can be used to produce a light-emitting device exhibiting a low operation voltage and a sufficiently high reverse voltage. The inventive method for producing a p-type Group III nitride semiconductor comprises, during lowering temperature after completion of growth of a Group III nitride semiconductor containing a p-type dopant, immediately after completion of the growth, starting, at a temperature at which the growth has been completed, supply of a carrier gas composed of an inert gas and reduction of the flow rate of a nitrogen source; and stopping supply of the nitrogen source at a time in the course of lowering the temperature.
1. A method for producing a Group III nitride semiconductor light-emitting device having an n-type contact layer, a light-emitting layer and a p-type contact layer on a substrate, wherein the method comprises, during lowering temperature after completion of growth of the p-type contact layer composed of AlGaN containing a p-type dopant,
immediately after the completion of the growth, starting, at a temperature at which the growth has been completed, supply of a carrier gas composed of an inert gas and reduction of a flow rate of a nitrogen source, wherein the flow rate of the nitrogen source after the reduction is 0.001% to 10% with respect to a flow rate of the total volume of gas; and
stopping supply of the nitrogen source at 700° C. to 950° C. in the course of lowering temperature.
2. A production method according to claim 1 , wherein the temperature when the growth has been completed is 900° C. or higher.
3. A production method according to claim 1 , wherein the nitrogen source is ammonia gas.
4. A production method according to claim 1 , wherein a carrier gas employed during growth of the semiconductor contains hydrogen gas.