Sharp Kabushiki Kaisha Corporation

Akira Aso

Hitoshi Kawanabe

Zempei Tani

Toshihumi Yoshikawa

A field effect semiconductor device comprises a P-N junction with a depletion layer responsive to radiant energy for controllably enabling the field effect semiconductor device. The depletion layer occurs near at least a pair of gate locations within a silicon substrate. The gate locations are of P-type while the silicon substrate is of N-type. The depletion layer is rendered ineffective by photoelectromotive force derived from the radiant energy. A channel emerges according to the shrinkage of the depletion layer to thereby provide electrical connection between a source and drain electrodes of the field effect transistor.

Light-responsive field effect mode semiconductor devices

A photoelectric semiconductor device is disclosed which exhibits a reduced spectral sensitivity in a desired wavelength zone. An N(P) type impurity region is formed in a P(N) type semiconductor substrate to establish a first PN junction functioning as a first photodiode. A P(N) type impurity region is shallowly formed in the N(P) type impurity region to establish a second PN junction functioning as a second photodiode. When the first PN junction is shunted, the photoelectric semiconductor device shows a spectral sensitivity which is reduced in the longer wavelength zone. Contrarily, when the second PN junction is shunted, the photoelectric semiconductor device shows the spectral sensitivity which is reduced in the shorter wavelength zone.

Dual junction photoelectric semiconductor device

Disclosed is a solid state wavelength detection system responding to output signals derived from a photoelectric semiconductor device. The photoelectric semiconductor device comprise at least two PN junctions formed at different depth from the surface of the semiconductor substrate. A deeper PN junction develops an output signal related to longer wavelength component of the light impinging thereon. A shallower PN junction develops an output signal related to shorter wavelength component of the impinging light. These two output signals are logarithmically compressed and compared with each other. Difference of the logarithmically compressed output signals represents the wavelength information of the impinging light.

Growing community of inventors

Nara, Japan

Akira Aso