摘要:
In order to improve reliability by preventing edge breakdown in a semiconductor photodetector having a mesa structure such as a mesa APD, the semiconductor photodetector includes a mesa structure formed on a first semiconductor layer of the first conduction type formed on a semiconductor substrate, the mesa structure including a light absorbing layer for absorbing light, an electric field buffer layer for dropping an electric field intensity, an avalanche multiplication layer for causing avalanche multiplication to occur, and a second semiconductor layer of the second conduction type, wherein the thickness of the avalanche multiplication layer at the portion in the vicinity of the side face of the mesa structure is made thinner than the thickness at the central portion of the mesa structure.
摘要:
In order to improve reliability by preventing an edge breakdown in a semiconductor photodetector having a mesa structure such as a mesa APD, the semiconductor photodetector includes a mesa structure formed on a first semiconductor layer of the first conduction type formed on a semiconductor substrate, the mesa structure including a light absorbing layer for absorbing light, an electric field buffer layer for dropping an electric field intensity, an avalanche multiplication layer for causing avalanche multiplication to occur, and a second semiconductor layer of the second conduction type, wherein the thickness of the avalanche multiplication layer at the portion in the vicinity of the side face of the mesa structure is made thinner than the thickness at the central portion of the mesa structure.
摘要:
In order to improve reliability by preventing an edge breakdown in a semiconductor photodetector having a mesa structure such as a mesa APD, the semiconductor photodetector comprises a mesa structure formed on a first semiconductor layer of the first conduction type formed on a semiconductor substrate, the mesa structure including a light absorbing layer for absorbing light, an electric field buffer layer for dropping an electric field intensity, an avalanche multiplication layer for causing avalanche multiplication to occur, and a second semiconductor layer of the second conduction type, wherein the thickness of the avalanche multiplication layer at the portion in the vicinity of the side face of the mesa structure is made thinner than the thickness at the central portion of the mesa structure.
摘要:
In order to improve reliability by preventing an edge breakdown in a semiconductor photodetector having a mesa structure such as a mesa APD, the semiconductor photodetector comprises a mesa structure formed on a first semiconductor layer of the first conduction type formed on a semiconductor substrate, the mesa structure including a light absorbing layer for absorbing light, an electric field buffer layer for dropping an electric field intensity, an avalanche multiplication layer for causing avalanche multiplication to occur, and a second semiconductor layer of the second conduction type, wherein the thickness of the avalanche multiplication layer at the portion in the vicinity of the side face of the mesa structure is made thinner than the thickness at the central portion of the mesa structure.
摘要:
A semiconductor photodetection device includes a photodetection layer formed of an alternate and repetitive stacking of an optical absorption layer accumulating therein a compressive strain and a stress-compensating layer accumulating therein a compensating tensile strain, wherein the optical absorption layer has a thickness larger than a thickness of the stress-compensating layer.
摘要:
There is provided a brass free from lead (Pb) and possessing excellent machinability, castability, mechanical properties and other properties. A brass consisting of not less than 55% by weight and not more than 75% by weight of copper (Cu), not less than 0.3% by weight and not more than 4.0% by weight of bismuth (Bi), and y % by weight of boron (B) and x % by weight of silicon (Si), y and x satisfying the following requirements: 0≦x≦2.0, 0≦y≦0.3, and y>−0.15x+0.015ab, wherein a is 0.2 when Bi is 0.3% by weight ≦Bi
摘要:
Disclosed is an image scanning unit which has: a CCD substrate which is mounted on a block; three groups of adjustment fastening members to position the CCD substrate in three dimensional directions orthogonal to one another; and a springy member to press each of the adjustment fastening members against receiving part of each of the adjustment fastening members; wherein the three groups of adjustment fastening members are of a first group of fastening members to conduct the focus adjustment by independently positioning the CCD substrate in a direction perpendicular to the plane of the CCD substrate at both ends of CCD in the longitudinal direction, a second group of fastening members to conduct the sub-scanning adjustment by independently positioning the CCD substrate in a direction orthogonal to the longitudinal direction of the CCD substrate within the plane of the CCD substrate at both ends of CCD in the longitudinal direction, and a third group of fastening member tot conduct the main-scanning adjustment by independently positioning the CCD substrate in a direction along the longitudinal direction of the CCD substrate within the plane of the CCD substrate.
摘要:
A group III-V compound semiconductor laser of a 1 .mu.m band having an excellent conversion efficiency and a high characteristic temperature. The semiconductor laser can emit light in a 1.3 .mu.m band or a 1.55 .mu.m, and has a laser structure including an active layer For emitting light, guide layers sandwiching the active layer and having a band gap larger than the active layer, and clad layers embracing the guide layers and having a band gap larger than the guide layers. The lattice constants of the guide layers and clad layers are larger than a1 by 0.5% or more and smaller than a2 by 0.5% or more, where a1 represents the lattice constant of GaAs and a2 is the lattice constant of InP.
摘要:
A document conveying device, include a conveyance roller which conveys a document that is attached to a conveyance roller shaft; and a flywheel connected to the conveyance roller shaft.
摘要:
An image scanner apparatus is composed of a housing, an optical unit positioned in the housing, a drive mechanism driving the optical unit. The drive mechanism includes first and second wires connected to the optical unit, and a drive motor driving the first and second wires. One end of the first wire is connected to a first fixture, and one end of the second wire is connected to a second fixture. The first fixture is secured to a first wire-retaining member positioned outside the housing at a first securing position, and the first wire-retaining member retains the first fixture so that the first securing position is adjustable.