Solar cell with anti-reflection structure and method for fabricating the same

Abstract

A solar cell with an anti-reflection structure comprises a solar cell substrate, a meshed electric-conduction layer formed on one surface of the solar cell substrate, a plurality of microspheres disposed on the meshed electric-conduction layer, and a dielectric layer. The microspheres have a diameter of 0.1-50 μm. The dielectric layer is formed between the meshed electric-conduction layer and the microspheres, and has a thickness smaller than the diameter of the microspheres to make the microspheres protrude from the dielectric layer. The meshed electric-conduction layer is formed via a screen-printing method. The present invention uses the microspheres and the meshed electric-conduction layer to achieve an excellent anti-reflection effect. Further, the present invention has the advantages of a simple fabrication process and a low fabrication cost.

What is claimed is: 
     
         1 . A solar cell with an anti-reflection structure, comprising;
 a solar cell substrate;   a meshed electric-conduction layer formed on one surface of the solar cell substrate;   a plurality of microspheres disposed on the meshed electric-conduction layer and having a diameter of 0.1-50 μm; and   a dielectric layer formed between the meshed electric-conduction layer and the microspheres, and having a thickness smaller than the diameter of the microspheres to make the microspheres protrude from the dielectric layer.   
     
     
         2 . The solar cell with the anti-reflection structure according to  claim 1 , wherein the meshed electric-conduction layer includes a plurality of accommodation spaces accommodating the microspheres. 
     
     
         3 . The solar cell with the anti-reflection structure according to  claim 1 , wherein the solar cell substrate includes a bottom electrode far away from the meshed electric-conduction layer, a P-type semiconductor layer, and an N-type semiconductor layer neighboring the meshed electric-conduction layer, which are arranged in sequence. 
     
     
         4 . The solar cell with the anti-reflection structure according to  claim 1 , wherein the meshed electric-conduction layer is made of a material selected from a group consisting of silver, aluminum, and a combination thereof. 
     
     
         5 . The solar cell with the anti-reflection structure according to  claim 1 , wherein the microspheres are made of a material selected from a group consisting of silicon dioxide, silicon nitride, and aluminum oxide. 
     
     
         6 . A method for fabricating a solar cell with an anti-reflection structure, comprising steps of:
 Step S 1 : preparing a solar cell substrate;   Step S 2 : using a screen-printing method to form a meshed electric-conduction layer on a surface of the solar cell substrate;   Step S 3 : mixing a plurality of microspheres, which have a diameter of 0.1-50 μm, with a volatile solution to form a mixture solution, and spraying the mixture solution on the meshed electric-conduction layer to allow the microspheres to be disposed on the meshed electric-conduction layer; and   Step S 4 : using a spin-coating method to coat an SOD (Spin on Dielectric) material between the meshed electric-conduction layer and the microspheres to form a dielectric layer, wherein the diameter of the microspheres is greater than a sum of thicknesses of the dielectric layer and the meshed electric-conduction layer.   
     
     
         7 . The method for fabricating the solar cell with the anti-reflection structure according to  claim 6 , wherein in the Step S 1 , N-type ions are doped into a P-type semiconductor layer to form an N-type semiconductor layer. 
     
     
         8 . The method for fabricating the solar cell with the anti-reflection structure according to  claim 6  further comprising a Step S 3 A: heating the solar cell substrate to a temperature of 80-110° C. to evaporate the volatile solution, wherein the Step S 3 A is interposed between the Step S 3  and the Step S 4 . 
     
     
         9 . The method for fabricating the solar cell with the anti-reflection structure according to  claim 6  further comprising a Step S 5 : using an electron-beam evaporation method to form a bottom electrode on one surface of the solar cell substrate, which is far away from the meshed electric-conduction layer, wherein the Step S 5  succeeds to the Step S 4 . 
     
     
         10 . The method for fabricating the solar cell with the anti-reflection structure according to  claim 6 , wherein the microspheres are made of a material selected from a group consisting of silicon dioxide, silicon nitride, and aluminum oxide.