Solar cell and method for producing the same

Claim 1

A polycrystalline silicon solar cell utilizing single crystals grown by selective crystal growth from small nucleation surfaces provided on a non-nucleation surface, wherein dangling bonds in the areas of crystal grain boundaries formed by mutual contact of said single crystals are terminated by hydrogen atoms and a semiconductor providing a photoelectromotive force is formed so as to exclude the areas of said crystal grain boundaries.

Claim 3

A method for producing a polycrystalline solar cell, comprising the steps of: 1) forming a non-nucleation surface and a plurality of spaced apart nucleation surfaces on a substrate; 2) selectively growing single crystals on the nucleation surfaces of said substrate to form a continuous polycrystalline film of one conductivity type; 3) forming a masking material on said continuous polycrystalline film with apertures so as to exclude areas of crystal grain boundaries formed by mutual contact of said single crystals; 4) forming a semiconductor junction in the portions of said single crystals exposed through said apertures of said masking material; 5) removing said masking material; and 6) forming a transparent conductive layer on said continuous polycrystalline film and a current collecting electrode on said transparent conductive material.

Claim 4

A method for producing a polycrystalline solar cell, comprising the steps of: 1) forming a non-nucleation surface and a plurality of spaced apart nucleation surfaces on a substrate; 2) selectively growing single crystals on the nucleation surfaces of said substrate to form a continuous polycrystalline film of one conductivity type; 3) forming a masking material on said continuous polycrystalline film with apertures so as to exclude areas of crystal grain boundaries formed by mutual contact of said single crystals; 4) forming a semiconductor junction in the portions of said single crystals exposed through said apertures of said masking material; 5) removing said masking material; and 6) forming a transparent conductive layer on said continuous polycrystalline film and a current collecting electrode on said transparent conductive material.

Claim 9

A method for producing a polycrystalline solar cell, comprising the steps of: 1) forming a non-nucleation surface and a plurality of spaced apart nucleation surfaces on a substrate; 2) selectively growing single crystals on the nucleation surfaces of said substrate to form a continuous polycrystalline film of one conductivity type; 3) forming, on said continuous polycrystalline film, a material composed of silicon atoms, nitrogen atoms and hydrogen atoms with apertures so as to exclude areas of crystal grain boundaries formed by mutual contact of said single crystals, and introducing a dopant impurity of opposite conductivity type through said apertures into the exposed surfaces of said single crystals; 4) effecting passivation of said grain boundaries with hydrogen atoms and forming a semiconductor junction in said single crystals; and 5) forming a transparent conductive layer on said continuous polycrystalline film, and a current-collecting electrode on said transparent conductive layer.

Claim 10

A method for producing a polycrystalline solar cell, comprising the steps of: 1) forming a non-nucleation surface and a plurality of spaced apart nucleation surfaces on a substrate; 2) selectively growing single crystals on the nucleation surfaces of said substrate to form a continuous polycrystalline film of one conductivity type; 3) forming, on said continuous polycrystalline film, a material composed of silicon atoms, nitrogen atoms and hydrogen atoms with apertures so as to exclude areas of crystal grain boundaries formed by mutual contact of said single crystals, and introducing a dopant impurity of opposite conductivity type through said apertures into the exposed surfaces of said single crystals; 4) effecting passivation of said grain boundaries with hydrogen atoms and forming a semiconductor junction in said single crystals; and 5) forming a transparent conductive layer on said continuous polycrystalline film, and a current-collecting electrode on said transparent conductive layer.