SOLAR CELL MANUFACTURING METHOD

摘要

The present application can easily realize a selective emitter structure by including the following steps: a first step that coats a portion of one surface of a first conductive-type semiconductor substrate (2) with a paste (21) that contains a second conductive-type impurity element; a second step that, inside a processing chamber, applies a first heat treatment to the semiconductor substrate in a gas atmosphere that does not contain the second conductive type impurity element and causes diffusion of the second conductive type impurity element from the paste to the lower region of the paste on the semiconductor substrate, thereby forming in the lower region of the paste on the semiconductor substrate a first impurity diffusion layer (3a) in which the second conductive type impurity element is diffused at a first concentration; and a third step that, inside the processing chamber, following the first heat treatment, applies a second heat treatment to the semiconductor substrate in a gas atmosphere that contains a dopant that contains the second conductive type impurity element and causes diffusion of the second conductive type impurity element from the gas containing the dopant to an exposed region not coated with paste on the one side of the semiconductor substrate, thereby forming on the exposed region a second impurity diffusion layer (3b) in which the second conductive type impurity element is diffused at a second concentration, which is lower than the first concentration.