Method for manufacturing single-crystal silicon solar cell and single-crystal silicon solar cell

1. A method for manufacturing a single-crystal silicon solar cell in which at least a metal substrate, a single-crystal silicon layer as a light conversion layer, and a transparent protective film are laminated and the transparent protective film side serves as a light receiving surface, the method comprising the steps of:

preparing the metal substrate and a single-crystal silicon substrate which is of a first conductivity type;

implanting at least one of a hydrogen ion and a rare gas ion into the single-crystal silicon substrate to form an ion implanted layer;

forming a transparent insulator layer having light scattering properties on the metal substrate, the light scattering properties being provided by light scattering particles in the transparent insulator layer or vacancies therein;

performing a surface activation treatment with respect to at lest one of the ion implanted surface of the single-crystal silicon substrate and a surface of the transparent insulator layer on the metal substrate;

bonding the ion implanted surface of the single-crystal silicon substrate to the surface of the transparent insulator layer on the metal substrate;

giving an impact shock to the ion implanted layer and mechanically delaminating the single-crystal silicon substrate to provide the single-crystal silicon layer;

forming a plurality of diffusion regions which are of a second conductivity type different from the first conductivity type in the delaminated surface side of the single-crystal silicon layer and forming a plurality of p-n junctions in at least a plane direction so that a plurality of first conductivity type regions and the plurality of second conductivity type regions are present in the delaminated surface of the single-crystal silicon layer;

forming a plurality of first individual electrodes on the plurality of first conductivity type regions of the single-crystal silicon layer and forming a plurality of second individual electrodes on the plurality of second conductivity type regions of the same;

forming a first collecting electrode connecting the plurality of first individual electrodes and a second collecting electrode connecting the plurality of second individual electrodes; and

forming a transparent protective film that covers the plurality of first conductivity type regions and the plurality of second conductivity type regions.

2. The method for manufacturing a single-crystal silicon solar cell according to claim 1 , wherein the metal substrate has a reflectivity of 60% or above with respect to a visible light.

3. The method for manufacturing a single-crystal silicon solar cell according to claim 1 , wherein the transparent insulator layer contains at least one of a silicon oxide, a silicon nitride, and an aluminum oxide.

4. The method for manufacturing a single-crystal silicon solar cell according to claim 2 , wherein the transparent insulator layer contains at least one of a silicon oxide, a silicon nitride, and an aluminum oxide.

5. The method for manufacturing a single-crystal silicon solar cell according to claim 1 , wherein the surface activation treatment is at least one of a plasma treatment and an ozone treatment.

6. The method for manufacturing a single-crystal silicon solar cell according to claim 4 , wherein the surface activation treatment is at least one of a plasma treatment and an ozone treatment.

7. The method for manufacturing a single-crystal silicon solar cell according to claim 1 , wherein a depth of the ion implantation is set to fall within the range of 2 μm to 50 μm from the ion implanted surface.

8. The method for manufacturing a single-crystal silicon solar cell according to claim 6 , wherein a depth of the ion implantation is set to fall within the range of 2 μm to 50 μm from the ion implanted surface.

9. The method for manufacturing a single-crystal silicon solar cell according to claim 1 , wherein the transparent protective film has light scattering properties.