Patent ID: 8546685

Claim:
A crystalline silicon based solar cell, comprising: a crystalline silicon substrate of one conductivity type having a light-incident-side main surface and an other main surface side opposite the light-incident side; a light-incident-side i-type silicon based thin film layer, a silicon based thin film layer of a conductivity type opposite the one conductivity type, a light-incident-side transparent conductive layer, and a collector electrode that are formed over the light-incident-side main surface of the crystalline silicon substrate in this order from the light-incident-side main surface; and a back-side i-type silicon based thin film layer, a silicon based thin film layer of the one conductivity type, a back-side transparent conductive layer, and a metal electrode layer that are formed over the other main surface side of the crystalline silicon substrate in this order from the other main surface side, wherein the crystalline silicon substrate has a thickness of 50 to 200 μm, and has a rough structure on at least the light-incident-side main surface thereof, a light-incident-side surface of the light-incident-side transparent conductive layer has an irregular structure, a top-bottom distance of the irregular structure of the light-incident-side transparent conductive layer is smaller than a top-bottom distance of the light-incident-side rough structure of the light-incident-side main surface of the crystalline silicon substrate, an apex distance of the irregular structure of the light-incident-side transparent conductive layer is smaller than an apex distance of the light-incident-side rough structure of the light-incident-side main surface of the crystalline silicon substrate, the light-incident-side transparent conductive layer comprises a zinc oxide layer having a thickness of 300 to 2500 nm, the zinc oxide layer comprises hexagonal zinc oxide preferentially oriented along a (10-10) plane direction, a (11-20) plane direction, or a (10-11) plane direction, and the hexagonal zinc oxide has a lattice constant in a range from 0.3225 nm to 0.3246 nm along an a-axis.