Process for producing layered member and layered member
The object is to provide a photoelectric surface member which allows higher quantum efficiency. In order to achieve this object, a photoelectric surface member 1 a is a crystalline layer formed by a nitride type semiconductor material, and comprises a nitride semiconductor crystal layer 10 where the direction from the first surface 101 to the second surface 102 is the negative c polar direction of the crystal, an adhesive layer 12 formed along the first surface 101 of the nitride semiconductor crystal layer 10 , and a glass substrate 14 which is adhesively fixed to the adhesive layer 12 such that the adhesive layer 12 is located between the glass substrate 14 and the nitride semiconductor crystal layer 10.
1. A photoelectric surface member manufacturing method of manufacturing a photoelectric surface member for forming a photoelectric surface which emits photoelectrons excited by incident light, comprising the steps of:
preparing a substrate for crystal growth which is a crystalline substance with the main surface in the (111) plane orientation;
forming a buffer layer along the main surface of said substrate for crystal growth;
forming a nitride semiconductor crystal layer as a light absorbing layer on said buffer layer by crystal growth in the Group III element surface (positive c polar) direction using a Group III-V nitride type semiconductor material;
forming an adhesive layer on a first surface which is a positive c polar surface of said nitride semiconductor crystal layer;
adhesively fixing a glass substrate which is formed to transmit incident light onto said adhesive layer;
removing said substrate for crystal growth to obtain said buffer layer with a negative c polar surface;
removing said buffer layer to obtain said nitride semiconductor crystal layer having a second surface which is a negative c polar surface after the step of removing said substrate for crystal growth; and
forming a layer containing alkali metal on the second surface of said nitride semiconductor crystal layer, wherein
in said nitride semiconductor crystal layer, the first surface is an incidence surface where the light transmitted through the glass substrate enters, and the second surface is an emission surface which emits photoelectrons excited by the incident light through the layer containing alkali metal.
2. The manufacturing method according to claim 1 , further comprising, prior to the step of removing the substrate for crystal growth, a step of forming a protective layer which covers at least the periphery of said glass substrate.
3. The manufacturing method according to claim 1 , wherein the substrate for crystal growth is a Si substrate with the (111) plane orientation.
4. The manufacturing method according to claim 3 , wherein the buffer layer is an AlN layer, or an AlN/GaN superlattice layer.
5. The manufacturing method according to claim 1 , wherein the substrate for crystal growth is a GaAs substrate with the (111)A plane orientation.
6. The manufacturing method according to claim 5 , wherein the buffer layer is an InGaAsN layer.
7. The manufacturing method according to claim 1 , wherein the substrate for crystal growth is a GaP substrate with the (111)A plane orientation.
8. The manufacturing method according to claim 7 , wherein the buffer layer is an InGaPN layer.
9. The manufacturing method according to claim 1 , wherein the nitride semiconductor crystal layer is a GaN layer, an AlGaN layer, or an InGaN layer.
10. The manufacturing method according to claim 1 , further comprising, after the step of forming the nitride semiconductor crystal layer, a step of forming an electron stopping layer with a bandgap larger than that of the nitride semiconductor crystal layer.
11. The manufacturing method according to claim 10 , wherein the electron stopping layer is an AlN layer, an AlGaN layer, or a BGaN layer.