Fujitsu Corporation

Technical Research & Development Institute Ministry of Defense of Japan

Yusuke Matsukura

Hironori Nishino

Yasuhito Uchiyama

Toshio Fujii

Mitsuhiro Nagashima

Michiya Kibe

Hitoshi Tanaka

Toshihide Kikkawa

Kozo Makiyama

Satoru Asai

Masahiko Takikawa

Yoshihiro Miyamoto

Hiroyasu Yamashita

Nobuyuki Kajihara

Mitsunori Yokoyama

Toshihiro Okamura

Minoru Doshida

An infrared detection apparatus includes an infrared detector configured to output an electric signal corresponding to an inputted infrared ray, and a signal processor configured to compensate for a variation of the electric signal, which is outputted from the infrared detector, caused by variation of an operation temperature with a value indicating a variation of a dark current equivalent component by the operation temperature variation when becoming a second operation temperature after the operation temperature variation, the dark current equivalent component including a first dark current equivalent component calculated using a first electric signal and a second electric signal outputted from the infrared detector when infrared rays having intensities equivalent to blackbodies of a first known temperature and a second known temperature are inputted at a first operation temperature.

Infrared detection apparatus

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

The infrared photodetector includes a contact layer formed over a semiconductor substrate, a quantum dot stackformed on the contact layerand including intermediate layersand quantum dotswhich are alternately stacked, and a contact layerformed on the quantum dot stack. One of the plurality of intermediate layers, which is in contact with the contact layer, has an n-type impurity doped regionformed on a side nearer the interface with the contact 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

A photodetecting device which is capable of performing photodetection with a high sensitivity in a wide temperature range. A quantum dot structure including an embedding layer and quantum dots embedded by the embedding layer is formed. A quantum well structure including embedding layers and a quantum well layer whose band gap is smaller than those of the embedding layers is formed at a location downstream of the quantum dot structure in the direction of flow of electrons which flow perpendicularly to the quantum dot structure during operation of the photodetecting device. This reduces the temperature dependence of the potential barrier of a photodetecting section, which has to be overcome by electrons, whereby it is possible to lower the potential barrier of the embedding layers at high temperature.

Photodetecting device and method of manufacturing the same

A multi-quantum well infrared photo-detector, in which a plurality of multi-quantum well layers having respective sensitivities for different wavelength ranges of infrared are layered via a common contact layer. The infrared photo-detector includes a switch where one end is connected to the above common contact layer, and a current integration unit which is connected to the other end of the above switch. First and second voltages are applied to first and second contact layers at the opposite side of first and second multi-quantum well layer respectively. The above switch is conducted for a predetermined time so that either voltage between the above common contact layer and the first contact layer or voltage between the above common contact layer and the second contact layer becomes higher than the other, and the above current integration unit is charged or discharged by the current which flows in the above multi-quantum well layers.

Multi-quantum well infrared photo-detector

The optical semiconductor device comprises a first contact layer formed on a substrate ; a first quantum well layer formed on the first contact layer; a second contact layer formed on the first quantum well layer; an optical coupling layer formed on the second contact layer; and a first conductor plug extended from an upper surface of the optical coupling layer and arriving at the first contact layer.

Optical semiconductor device and method for fabricating the same

A method of fabricating a compound semiconductor device includes a step of removing a semiconductor layer by an etching process to expose an upper major surface of an underlying semiconductor layer, followed by a growth of another semiconductor layer of the p-type on the surface thus exposed, wherein the exposed surface is cleaned by a flushing of a gaseous metal organic compound containing a group V element for removing impurities therefrom and further doping the exposed surface to the p-type.

Growing community of inventors

Kawasaki, Japan

Yusuke Matsukura