Abstract: Provided are a semiconductor device and an optical sensor device, each having reduced dark current, and detectivity extended toward longer wavelengths in the near-infrared. Further, a method for manufacturing the semiconductor device is provided. The semiconductor device 50 includes an absorption layer 3 of a type II (GaAsSb/InGaAs) MQW structure located on an InP substrate 1, and an InP contact layer 5 located on the MQW structure. In the MQW structure, a composition x (%) of GaAsSb is not smaller than 44%, a thickness z (nm) thereof is not smaller than 3 nm, and z??0.4x+24.6 is satisfied.

Abstract: An image pickup device, a visibility support apparatus, a night vision device, a navigation support apparatus, and a monitoring device are provided in which noise and dark current are suppressed to thereby provide clear images regardless of whether it is day or night. The device includes a light-receiving layer 3 having a multi-quantum well structure and a diffusion concentration distribution control layer 4 disposed on the light-receiving layer so as to be opposite an InP substrate 1, wherein the light-receiving layer has a band gap wavelength of 1.65 to 3 ?m, the diffusion concentration distribution control layer has a lower band gap energy than InP, a pn junction is formed for each light-receiving element by selective diffusion of an impurity element, and the impurity selectively diffused in the light-receiving layer has a concentration of 5×1016/cm3 or less.

Abstract: Provided are a light-receiving element which has sensitivity in the near-infrared region and in which a good crystal quality is easily obtained, a one-dimensional or two-dimensional array of the light-receiving elements is easily formed with a high accuracy, and a dark current can be reduced; a light-receiving element array; and methods for producing the same. A light-receiving element includes a group III-V compound semiconductor stacked structure including an absorption layer 3 having a pn-junction 15 therein, wherein the absorption layer has a multiquantum well structure composed of group III-V compound semiconductors, the pn-junction 15 is formed by selectively diffusing an impurity element into the absorption layer, and the concentration of the impurity element in the absorption layer is 5×1016 cm?3 or less.

Abstract: A light receiving device having small dark current and capable of sensing light in the wavelength range of 2.0 ?m to 3.0 ?m with high sensitivity is provided. The light receiving device has an InP substrate, and a light receiving layer formed by alternately stacking a larger layer formed of GaInNAsSbP mixed crystal having nitrogen content of at most 5% in 5 group, larger lattice constant than that of InP and thickness between hc and 11hc, the critical thickness hc being determined as hc=b(1?? cos2?){log(hc/b)+1}/8?f(1+?)cos ? and a smaller layer formed of GaInNAsSbP mixed crystal having nitrogen content of at most 5% in 5 group, smaller lattice constant than that of InP and thickness between hc and 11hc; absolute value of lattice mismatch of the larger layer and the smaller layer to the InP substrate is at least 0.5% and at most 5%; at least one of the layers has absorption edge wavelength of 2.0 ?m to 3.0 ?m; total thickness of respective layers is 2.0 ?m to 4.

Abstract: Provided is a biological component detection device with which a biological component can be detected at high sensitivity by using an InP-based photodiode in which a dark current is reduced without using a cooling mechanism and the sensitivity is extended to a wavelength of 1.8 ?m or more. An absorption layer 3 has a multiple quantum well structure composed of group III-V semiconductors, a pn-junction 15 is formed by selectively diffusing an impurity element in the absorption layer, and the concentration of the impurity element in the absorption layer is 5×1016/cm3 or less, the diffusion concentration distribution control layer has an n-type impurity concentration of 2×1015/cm3 or less before the diffusion, the diffusion concentration distribution control layer having a portion adjacent to the absorption layer, the portion having a low impurity concentration.

Abstract: A light-receiving element device capable of receiving near infrared to mid-infrared light of 1.7 ?m-3.5 ?m is provided. A substrate is formed of InP, and a superlattice light-receiving layer is formed of a superlattice of a type 2 junction formed by alternately being stacked a falling layer of a Group III-V compound semiconductor including In, Ga, As, N and a rising layer of a Group III-V compound semiconductor including Ga, As, Sb. The film thickness of the falling layer and the rising layer is each 3 nm-10 nm. The entire thickness of the superlattice light-receiving layer is 2 ?m-7 ?m. The lattice mismatch of the constituent film of the superlattice light-receiving layer to InP is ±0.2% or less.

Abstract: A moisture detector includes a light-receiving element including an absorption layer having a pn-junction, or an array of the light-receiving elements, wherein the absorption layer has a multiquantum well structure composed of a Group III-V semiconductor, the pn-junction is formed by selectively diffusing an impurity element into the absorption layer, and the concentration of the impurity in the absorption layer is 5×1016/cm3 or less. The moisture detector receives light having at least one wavelength included in an absorption band of water lying in a wavelength range of 3 ?m or less, thereby detecting moisture.

Abstract: There is provided, for example, a food quality examination device configured to inspect the quality of food with high sensitivity using an InP-based photodiode in which a dark current is decreased without a cooling mechanism and the sensitivity is extended to a wavelength of 1.8 ?m or more. An absorption layer has a multiquantum well structure composed of a III-V group semiconductor. A pn junction is formed by selectively diffusing an impurity element into the absorption layer. The concentration of the impurity in the absorption layer is 5×1016/cm3 or less.

Abstract: An image pickup device, a visibility support apparatus, a night vision device, a navigation support apparatus, and a monitoring device are provided in which noise and dark current are suppressed to thereby provide clear images regardless of whether it is day or night. The device includes a light-receiving layer 3 having a multi-quantum well structure and a diffusion concentration distribution control layer 4 disposed on the light-receiving layer so as to be opposite an InP substrate 1, wherein the light-receiving layer has a band gap wavelength of 1.65 to 3 ?m, the diffusion concentration distribution control layer has a lower band gap energy than InP, a pn junction is formed for each light-receiving element by selective diffusion of an impurity element, and the impurity selectively diffused in the light-receiving layer has a concentration of 5×1016/cm3 or less.

Abstract: The present invention provides an image pickup device used to capture an image of an object by receiving light in a near infrared region reflected from the object. The image pickup device includes semiconductor light-receiving elements each having a light-receiving layer with a band gap wavelength of 1.65 to 3.0 ?m.

Abstract: Provided are a light-receiving element which has sensitivity in the near-infrared region and in which a good crystal quality is easily obtained, a one-dimensional or two-dimensional array of the light-receiving elements is easily formed with a high accuracy, and a dark current can be reduced; a light-receiving element array; and methods for producing the same. A light-receiving element includes a group III-V compound semiconductor stacked structure including an absorption layer 3 having a pn-junction 15 therein, wherein the absorption layer has a multiquantum well structure composed of group III-V compound semiconductors, the pn-junction 15 is formed by selectively diffusing an impurity element into the absorption layer, and the concentration of the impurity element in the absorption layer is 5×1016 cm?3 or less.

Abstract: A photodiode array for near infrared rays that includes photodiodes having a uniform size and a uniform shape, has high selectivity for the wavelength of received light between the photodiodes, and has high sensitivity with the aid of a high-quality semiconducting crystal containing a large amount of nitrogen, a method for manufacturing the photodiode array, and an optical measurement system are provided. The steps of forming a mask layer 2 having a plurality of openings on a first-conductive-type or semi-insulating semiconductor substrate 1, the openings being arranged in one dimension or two dimensions, and selectively growing a plurality of semiconductor layers 3a, 3b, and 3c including an absorption layer 3b in the openings are included.

Abstract: The invention offers a photodetector that has an N-containing InGaAs-based absorption layer having a sensitivity in the near-infrared region and that suppresses the dark current and a production method thereof. The photodetector is provided with an InP substrate 1, an N-containing InGaAs-based absorption layer 3 positioned above the InP substrate 1, a window layer 5 positioned above the N-containing InGaAs-based absorption layer 3, and an InGaAs buffer layer 4 positioned between the N-containing InGaAs-based absorption layer 3 and the window layer 5.

Abstract: A photodiode array includes a substrate of a common read-out control circuit; and a plurality of photodiodes arrayed on the substrate and each including an absorption layer, and a pair of a first conductive-side electrode and a second conductive-side electrode. In this photodiode array, each of the photodiodes is isolated from adjacent photodiodes, the first conductive-side electrodes are provided on first conductivity-type regions and electrically connected in common across all the photodiodes, and the second conductive-side electrodes are provided on second conductivity-type regions and individually electrically connected to read-out electrodes of the read-out control circuit.

Abstract: The present invention provides a semiconductor light emitting device capable of easily realizing stable output characteristics within a wide temperature range. The semiconductor light emitting device includes a semiconductor laser element, and a semiconductor photodiode having an absorption layer disposed on a semiconductor substrate, a second conductivity type region formed in a cap layer and the absorption layer, and a transmissive reflection film disposed on the back side of the semiconductor substrate. The semiconductor photodiode is mounted with the epitaxial layer side down, and the transmissive reflection film is irradiated with a laser beam emitted from the semiconductor laser element so that light reflected from the transmissive reflection film is used as output light, and transmitted light is received by the semiconductor photodiode and used for controlling the output of the semiconductor laser element.

Abstract: A light-receiving element device capable of receiving near infrared to mid-infrared light of 1.7 ?m-3.5 ?m is provided. A substrate is formed of InP, and a superlattice light-receiving layer is formed of a superlattice of a type 2 junction formed by alternately being stacked a falling layer of a Group III-V compound semiconductor including In, Ga, As, N and a rising layer of a Group III-V compound semiconductor including Ga, As, Sb. The film thickness of the falling layer and the rising layer is each 3 nm-10 nm. The entire thickness of the superlattice light-receiving layer is 2 ?m-7 ?m. The lattice mismatch of the constituent film of the superlattice light-receiving layer to InP is ±0.2% or less.

Abstract: A moisture detector includes a light-receiving element including an absorption layer having a pn-junction, or an array of the light-receiving elements, wherein the absorption layer has a multiquantum well structure composed of a Group III-V semiconductor, the pn-junction is formed by selectively diffusing an impurity element into the absorption layer, and the concentration of the impurity in the absorption layer is 5×1016/cm3 or less. The moisture detector receives light having at least one wavelength included in an absorption band of water lying in a wavelength range of 3 ?m or less, thereby detecting moisture.

Abstract: A light receiving device having small dark current and capable of sensing light in the wavelength range of 2.0 ?m to 3.0 ?m with high sensitivity is provided. The light receiving device has an InP substrate, and a light receiving layer formed by alternately stacking a larger layer formed of GaInNAsSbP mixed crystal having nitrogen content of at most 5% in 5 group, larger lattice constant than that of InP and thickness between hc and 11hc, the critical thickness hc being determined as hc=b(1?? cos2?){log(hc/b)+1}/8?f(1+?)cos ? and a smaller layer formed of GaInNAsSbP mixed crystal having nitrogen content of at most 5% in 5 group, smaller lattice constant than that of InP and thickness between hc and 11hc; absolute value of lattice mismatch of the larger layer and the smaller layer to the InP substrate is at least 0.5% and at most 5%; at least one of the layers has absorption edge wavelength of 2.0 ?m to 3.0 ?m; total thickness of respective layers is 2.0 ?m to 4.

Abstract: There is provided an image pickup device which picks up an image of an object by absorbing light in a near infrared region reflected from the object and which has semiconductor photodetectors including an absorption layer of a bandgap wavelength in the range of 1.65 to 3.0 ?m.

Abstract: A rear-illuminated-type photodiode array has (a) a first-electroconductive-type semiconductor substrate, (b) a first-electroconductive-type electrode that is placed at the rear side of the semiconductor substrate and has openings arranged one- or two-dimensionally, (c) an antireflective coating provided at each of the openings of the first-electroconductive-type electrode, (d) a first-electroconductive-type absorption layer formed at the front-face side of the substrate, (e) a leakage-lightwave-absorbing layer that is provided on the absorption layer and has an absorption edge wavelength longer than that of the absorption layer, (f) a plurality of second-electroconductive-type regions that are formed so as to penetrate through the leakage-lightwave-absorbing layer from the top surface and extend into the absorption layer to a certain extent and are arranged one- or two-dimensionally at the positions coinciding with those of the antireflective coatings at the opposite side, and (g) a second-electroconductive-t