| 摘要 |
<p>To obtain a photovoltaic power device that can improve the photoelectric conversion efficiency more than that of conventional techniques without degrading the efficiency of extracting a photocurrent to an external circuit. A photovoltaic power device includes a P-type silicon substrate 101, a low-resistance N-type diffusion layer 102L diffused with an N-type impurity in a first concentration formed at a light-incidence surface side, grid electrodes 111 formed on the low-resistance N-type diffusion layer 102L, a P+ layer 110 formed on a back surface, and a back surface electrode formed on the P+ layer 110. The photovoltaic power device has concave portions 106 provided at a predetermined interval to reach the silicon substrate 101 from an upper surface of the low-resistance N-type diffusion layer 102L, and an upper surface of a region between adjacent concave portions 106 includes the low-resistance N-type diffusion layer 102L. A high-resistance N-type diffusion layer 102H diffused with an N-type impurity in a second concentration, which is lower than the first concentration, is formed in a range of a predetermined depth from a formation surface of the concave portions 106.</p> |
