Abstract: An infrared detecting device is provided. The infrared detecting device includes: a semiconductor substrate; a first layer having a first conductivity type on the semiconductor substrate; a light receiving layer on the first layer; and a second layer having a second conductivity type on the light receiving layer. A part of the first layer, the light receiving layer, and the second layer form a mesa structure. The second layer contains AlzIn1-zSb (0.05<z<0.18). The side surfaces and an upper surface of the mesa structure are covered with the protective layer. A part of an upper surface of the second layer that forms an interface between the second layer and the protective layer has an oxide layer made of a constituent material of the second layer. The oxide layer includes an oxide of Al and has no oxide of Sb.

Abstract: Disclosed is an infrared detecting device with a high SNR. The infrared detecting device 100 includes a semiconductor substrate 10; a first layer 20 formed on the semiconductor substrate and having a first conductivity type; a light receiving layer 30 formed on the first layer; and a second layer 40 formed on the light receiving layer and having a second conductivity type. The first layer includes, in the stated order: a layer containing Alx(1)In1-x(1)Sb; a layer having a film thickness ty(1) in nanometers and containing Aly(1)In1-y(1)Sb; and a layer containing Alx(2)In1-x(2)Sb, where ty(1), x(1), x(2), and y(1) satisfy the following relations: for j=1, 2, 0<ty(1)?2360×(y(1)?x(j))?240 (0.11?y(1)?x(j)?0.19), 0<ty(1)??1215×(y(1)?x(j))+427 (0.19<y(1)?x(j)?0.33), and 0<x(j)<0.18.

Abstract: Provided is an infrared detecting device with a high SNR. The infrared detecting device includes: a semiconductor substrate 10; a first layer 21 having a first conductivity type on the semiconductor substrate; a light receiving layer 22 on the first layer; and a second layer 23 having a second conductivity type on the light receiving layer. A part of the first layer, the light receiving layer, and the second layer form a mesa structure, the light receiving layer contains AlxIn1-xSb (0.05<x<0.18), and at least a part of side surfaces of the mesa structure are covered with a protective layer, and part of the protective layer that is in contact with side surfaces of the light receiving layer is made of silicon nitride.

Abstract: Provided is a high-performance infrared optical device including a reflecting layer structure that can be widely used in the mid-infrared region. An infrared optical device that has a light emission/reception property of having a peak at a center wavelength ? comprises: a semiconductor substrate; and a thin film laminate portion including a first reflecting layer formed on the semiconductor substrate, a lower semiconductor layer of a first conductivity type, a light emitting/receiving layer, an upper semiconductor layer of a second conductivity type, and a second reflecting layer in the stated order, wherein the first reflecting layer has a constituent material made of AlGaInAsSb where 0?Al+Ga?0.5 and 0?As?1.0, and includes a plurality of layers that differ in impurity concentration, and the center wavelength ? is 2.5 ?m or more at room temperature.

Abstract: Provided is an infrared detecting device with a high SNR. The infrared detecting device includes: a semiconductor substrate 10; a first layer 21 having a first conductivity type on the semiconductor substrate; a light receiving layer 22 on the first layer; and a second layer 23 having a second conductivity type on the light receiving layer. A part of the first layer, the light receiving layer, and the second layer form a mesa structure, the light receiving layer contains AlxIn1-xSb (0.05<x<0.18), and at least a part of side surfaces of the mesa structure are covered with a protective layer, and part of the protective layer that is in contact with side surfaces of the light receiving layer is made of silicon nitride.

Abstract: Provided is an infrared light emitting device with high emission intensity. The infrared light emitting device includes: a semiconductor substrate; a first compound semiconductor layer; a light emitting layer containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s); a third compound semiconductor layer; and a second compound semiconductor layer containing at least In, Al, and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), in which the first compound semiconductor layer includes, in the stated order, a first A layer, a first B layer, and a first C layer, each containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), and the proportion(s) of the Al composition or the Al composition and the Ga composition of each layer satisfy a predetermined relation(s).

Abstract: Provided is an infrared light emitting device with high emission intensity. The infrared light emitting device includes: a semiconductor substrate; a first compound semiconductor layer; a light emitting layer containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s); a third compound semiconductor layer; and a second compound semiconductor layer containing at least In, Al, and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), in which the first compound semiconductor layer includes, in the stated order, a first A layer, a first B layer, and a first C layer, each containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), and the proportion(s) of the Al composition or the Al composition and the Ga composition of each layer satisfy a predetermined relation(s).

Abstract: Provided is an infrared detecting device with high SNR. The infrared detecting device includes: a semiconductor substrate; a first compound semiconductor layer; a light receiving layer formed on the first compound semiconductor layer and containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s); a third compound semiconductor layer; and a second compound semiconductor layer containing at least In, Al, and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), in which the first compound semiconductor layer includes, in the stated order, a first A layer, a first B layer, and a first C layer, each containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), and the proportion(s) of the Al composition or the Al composition and the Ga composition of each layer satisfy a predetermined relation(s).

Abstract: Disclosed is an infrared light emitting device including: a semiconductor substrate; a first layer formed on the semiconductor substrate and having a first conductivity type; a light emitting layer formed on the first layer; and a second layer formed on the light emitting layer and having a second conductivity type, wherein the first layer includes, in the stated order: a layer containing Alx(1)In1?x(1)Sb; a layer having a film thickness ty(1) in nanometers and containing Aly(1)In1?y(1)Sb; and a layer containing Alx(2)In1?x(2)Sb, where ty(1), x(1), x(2), and y(1) satisfy the following relations: for j=1, 2, 0<ty(1)?2360×(y(1)?x(j))?240 (0.11?y(1)?x(j)?0.19), 0<ty(1)??1215×(y(1)?x(j))+427 (0.19<y(1)?x(j)?0.33), and 0<x(j)<0.18.

Abstract: Provided is an infrared detecting device with high SNR. The infrared detecting device includes: a semiconductor substrate; a first compound semiconductor layer; a light receiving layer formed on the first compound semiconductor layer and containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s); a third compound semiconductor layer; and a second compound semiconductor layer containing at least In, Al, and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), in which the first compound semiconductor layer includes, in the stated order, a first A layer, a first B layer, and a first C layer, each containing at least In and Sb and having a predetermined range(s) of Al or Al and Ga proportion(s), and the proportion(s) of the Al composition or the Al composition and the Ga composition of each layer satisfy a predetermined relation(s).

Abstract: Disclosed is an infrared detecting device with a high SNR. The infrared detecting device 100 includes a semiconductor substrate 10; a first layer 20 formed on the semiconductor substrate and having a first conductivity type; a light receiving layer 30 formed on the first layer; and a second layer 40 formed on the light receiving layer and having a second conductivity type. The first layer includes, in the stated order: a layer containing Alx(1)In1-x(1)Sb; a layer having a film thickness ty(1) in nanometers and containing Aly(1)In1-y(1)Sb; and a layer containing Alx(2)In1-x(2)Sb, where ty(1), x(1), x(2), and y(1) satisfy the following relations: for j=1, 2, 0<ty(1)?2360×(y(1)?x(j))?240 (0.11?y(1)?x(j)?0.19), 0<ty(1)??1215×(y(1)?x(j))+427 (0.19<y(1)?x(j)?0.33), and 0<x(j)<0.18.

Abstract: Disclosed is an infrared light emitting device including: a semiconductor substrate; a first layer formed on the semiconductor substrate and having a first conductivity type; a light emitting layer formed on the first layer; and a second layer formed on the light emitting layer and having a second conductivity type, wherein the first layer includes, in the stated order: a layer containing Alx(1)In1?x(1)Sb; a layer having a film thickness ty(1) in nanometers and containing Aly(1)In1?y(1)Sb; and a layer containing Alx(2)In1?x(2)Sb, where ty(1), x(1), x(2), and y(1) satisfy the following relations: for j=1, 2, 0<ty(1)?2360×(y(1)?x(j))?240 (0.11?y(1)?x(j)?0.19), 0<ty(1)??1215×(y(1)?x(j))+427 (0.19<y(1)?x(j)?0.33), and 0<x(j)<0.18.