Solar cell and method for fabricating the same
A solar cell includes a graphite substrate, an amorphous carbon layer having a thickness of not less than 20 nm and not more than 60 nm formed on the graphite substrate, an AlN layer formed on the amorphous carbon layer, a n-type nitride semiconductor layer formed on the AlN layer; a light-absorption layer including a nitride semiconductor layer formed on the n-type nitride semiconductor layer; a p-type nitride semiconductor layer formed on the light-absorption layer; a p-side electrode electrically connected to the p-type nitride semiconductor layer; and an n-side electrode electrically connected to the n-type nitride semiconductor layer. The amorphous carbon layer is obtained by oxidizing the surface of the graphite substrate.
1. A method for generating electric power with a solar cell, the method comprising steps of:
a step (a) of preparing the solar cell comprising:
a graphite substrate;
an amorphous carbon layer formed on the graphite substrate by oxygen-ashing treatment;
an AlN layer formed on the amorphous carbon layer;
a n-type nitride semiconductor layer formed on the AlN layer;
a light-absorption layer comprising a nitride semiconductor layer formed on the n-type nitride semiconductor layer;
a p-type nitride semiconductor layer formed on the light-absorption layer;
a p-side electrode electrically connected to the p-type nitride semiconductor layer; and
an n-side electrode electrically connected to the n-type nitride semiconductor layer;
wherein the amorphous carbon layer has a thickness of not less than 20 nanometers and not more than 60 nanometers; and
a step (b) of irradiating the solar cell with sunlight to generate the electric power between the p-side electrode and the n-side electrode.
2. The method according to claim 1 , wherein the p-side electrode is transparent.
3. The solar cell according to claim 1 , wherein the light-absorption layer includes a multi-layered structure.
4. The method according to claim 1 , wherein the p-side electrode is formed by a liquid phase synthesis.
5. The method according to claim 4 , wherein the p-side electrode is made of ZnO.