The invention belongs to the field of
heterojunction cells, and particularly discloses a
heterojunction cell and a preparation method thereof, which are characterized in that heavily doped
amorphous silicon is deposited in a corresponding area of a grid line
electrode, so that high parasitic absorption, surface
dangling bond and interface
state density are reduced, and the open
voltage and the efficiency of the
heterojunction cell are improved. The main technical scheme of the invention is as follows: according to the heterojunction
cell, grooves are formed in corresponding areas of grid line electrodes on the front surface and the back surface of an N-type
silicon substrate; arranging an intrinsic
amorphous silicon layer; the light
doping P-type
amorphous silicon layer is arranged on the front intrinsic amorphous
silicon layer, the light
doping N-type amorphous
silicon layer is arranged on the back intrinsic amorphous silicon layer, the heavy
doping P-type amorphous silicon layer is arranged in a groove corresponding area on the light doping P-type amorphous silicon layer, the heavy doping N-type amorphous silicon layer is arranged in a groove corresponding area on the light doping N-type amorphous silicon layer, and the light doping N-type amorphous silicon layer is arranged in a groove corresponding area on the light doping N-type amorphous silicon layer. The P-type doped amorphous silicon layer and the N-type doped amorphous silicon layer are respectively provided with a transparent
conductive oxide layer, and the grid line electrodes are arranged on the transparent
conductive oxide layers. The invention is mainly used for power generation.