Fujitsu Corporation

Technical Research & Development Institute Ministry of Defense of Japan

Yasuhito Uchiyama

Hironori Nishino

Yusuke Matsukura

Mitsuhiro Nagashima

Michiya Kibe

Toshio Fujii

Hiroyasu Yamashita

Nobuyuki Kajihara

Minoru Doshida

Toshihiro Okamura

An optical semiconductor device includes a lower electrode layer formed over a semiconductor substrate, an infrared absorption layer formed over the lower electrode layer, and an upper electrode layerformed over the infrared absorption layer. The infrared absorption layer includes a quantum dot having dimensions different among directions stacked, and is sensitive to infrared radiation of wavelengths different corresponding to polarization directions.

Optical semiconductor device with quantum dots having configurational anisotropy

An infrared photodetector including a layer structure of an intermediate layer, and a quantum dot layer having a narrower band gap than the intermediate layer and including a plurality of quantum dots alternately stacked, and detecting photocurrent generated when infrared radiation is applied to the layer structure to thereby detect the infrared radiation, the infrared photodetector further including a first barrier layer provided on one side of the quantum dot layer and having a larger band gap than the intermediate layer; and a second barrier layer provided on the other side of the quantum dot layer and having a larger band gap than the intermediate layer.

Infrared photodetector

A photo detector is provided with a plurality of quantum dot layers and first conductive type contact layers provided at both sides of the plurality of quantum dot layers so as to sandwich them; a second conductive type impurity is doped in a first semiconductor layer formed between one first conductive type contact layer and a first quantum dot layer which is closest to the one first conductive type contact layer so that it results in a barrier against a carrier positioned at the one first conductive contact layer.

Photo detector with a quantum dot layer

At least one or more dark current reducing layers having a quantum well structure are provided at an end portion in a stacking direction of an infrared detecting section in which quantum dot layers are stacked.

Infrared detector

Growing community of inventors

Kawasaki, Japan

Yasuhito Uchiyama