Mitsubishi Denki Kabushiki Kaisha

Nippon Telegraph and Telephone Corporation

Nobuyoshi Ogasawara

Kotaro Mitsui

Takahiko Oohara

Takashi Nishimura

Tadashi Kimura

Motoharu Miyashita

Masaaki Usui

Yoshiro Ohmachi

Yoshiaki Kadota

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.

Method for evaluating epitaxial layers and test pattern for process

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.

Manufacturing a gallium arsenide solar cell on a silicon substrate

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.

Photovoltaic semiconductor device

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.

Growing community of inventors

Itami, Japan

Nobuyoshi Ogasawara