Patent ID: 9082920
Filing Date: 2015-07-14
Classification: H01L,Y02E

Abstract:
1. A back contact solar cell comprising: a substrate made of crystalline silicon having a first conductivity type; a passivation layer on a front side of the substrate; an antireflection layer on the passivation layer; a first electrode on a rear side of the substrate; a second electrode on the rear side of the substrate and separated from the first electrode; a first semiconductor layer disposed between the first electrode and the substrate and having the first conductivity type; and a second semiconductor layer disposed between the second electrode and the substrate and having a second conductivity type that is opposite to the first conductivity type, wherein the passivation layer is formed on the front side of the substrate opposite to the rear side of the substrate where the first semiconductor layer and the second semiconductor layer are formed, wherein the passivation layer comprises: a first layer on the front side of the substrate, wherein the first layer includes amorphous silicon; and a second layer on the first layer, wherein the second layer includes at least one of amorphous silicon oxide, and wherein the first layer is disposed between the substrate and the second layer, wherein a light absorption coefficient of the second layer is lower than a light absorption coefficient of the first layer, wherein the second layer of the passivation layer has a bandgap energy of between about 1.8 eV and about 2.25 eV, and wherein the first layer of the passivation layer is a separate layer from the substrate, and the first layer of the passivation layer has a different crystalline structure from that of the substrate.