Abstract: In a method for evaluating thickness of a semiconductor layer epitaxially growing on a main surface of a substrate, a parallel stripe-shaped ridges extending are formed on the surface of the substrate, and a semiconductor layer is epitaxially grown on the surface of the substrate including the stripe-shaped ridges while irradiating the stripe-shaped ridges with light and monitoring from the stripe-shaped ridges to evaluate the thickness of the epitaxially growing semiconductor layer. The thickness of the epitaxial layer is evaluated with high precision during the epitaxial growth process.

Abstract: A method for manufacturing a solar cell which includes at least a first GaAs layer of a first conductivity type and a second GaAs layer of a second conducitivity type sequentially formed on a first main surface of an Si substrate of the first conductivity type, a first electrode formed on a second main surface opposite to the first main surface of the Si substrate and a second electrode formed on the second GaAs layer. The method includes a first step of forming a layer comprising a material having a thermal expansion coefficient smaller than that of Si on the second main surface of the Si substrate at a temperature close to room temperature and a second step of sequentially forming the first and second GaAs layers on the first main surface of the Si substrate.

Abstract: A photovoltaic semiconductor device includes a first conductivity type silicon substrate having a first main surface, a first conductivity type compound semiconductor layer disposed on a first, major portion of the first main surface of the silicon substrate, a second conductivity type compound semiconductor layer disposed on the first conductivity type compound semiconductor layer, a first electrode connected to the second conductivity type compound semiconductor layer, a portion of the first electrode being disposed on a second, minor portion of the first main surface of the silicon substrate with an intervening insulating film, and a second electrode disposed on a third, minor portion of the first main surface of the silicon substrate.

Abstract: A light responsive semiconductor includes a second conductivity type semiconductor substrate, a photoelectric conversion layer comprising semiconductor layers having a pn junction, which is disposed on the second conductivity type semiconductor substrate, a buffer layer comprising a second conductivity type semiconductor layer having a larger energy band gap than that of the photoelectric conversion layer. The element further includes a light reflection layer comprising a semiconductor layer which is disposed between the second conductivity type semiconductor substrate and the buffer layer. Alternatively, a light reflection layer which is a buffer layer is disposed between a photoelectric conversion layer and a semiconductor substrate.