Silicon based thin film solar cell
View Patent ↗According to the present invention, sufficient light trapping effect can be exhibited and series resistance can be kept small, by sequentially forming a silicon based low refractive index layer and a thin silicon based interface layer on a backside of a photoelectric conversion layer observed from a light incident side, and as a result a silicon based thin film solar cell may be provided efficiently and at low cost.
1. A silicon based thin film solar cell, wherein a conductive type silicon based low refractive index layer, a silicon based interface layer, and a back electrode are disposed and contact one another in this order on a backside of a photoelectric conversion layer observed from a light incident side, wherein the silicon based interface layer comprises a crystalline silicon component in the layer,
wherein the silicon based low refractive index layer comprises a crystalline silicon component in the layer,
wherein a most abundantly existing constituent element, excluding silicon, in the silicon based low refractive index layer is oxygen, which is present in an amount not less than 25 atomic %, and
wherein the silicon based low refractive index layer has a thickness of not less than 300 angstroms.
2. The silicon based thin film solar cell according to claim 1 , wherein the silicon based low refractive index layer has a refractive index not more than 2.5 at a wavelength of 600 nm.
3. The silicon based thin film solar cell according to claim 1 , wherein the silicon based interface layer has a thickness not more than 150 angstroms.
4. The silicon based thin film solar cell according to claim 1 , wherein the silicon based low refractive index layer and silicon based interface layer includes the same conductivity type.