Heterojunction solar cell and manufacturing method thereof

The invention provides a heterojunction solar cell and a manufacturing method thereof. The heterojunction solar cell comprises an N-type monocrystalline silicon wafer. A first intrinsic amorphous silicon layer, a third intrinsic amorphous silicon layer, an N-type amorphous silicon layer, a first transparent conductive film and a first electrode are sequentially formed on the front side of the N-type monocrystalline silicon wafer. A second intrinsic amorphous silicon layer, a fourth intrinsic amorphous silicon layer, a P-type amorphous silicon layer, a second transparent conducting film and a second electrode are sequentially formed on the back side of the N-type monocrystalline silicon wafer. The first intrinsic amorphous silicon layer and the second intrinsic amorphous silicon layer are formed through a first intrinsic PECVD process with the process gas being silane not doped with hydrogen. The third intrinsic amorphous silicon layer is formed through a second intrinsic PECVD process with process gases inclu