摘要:
A semiconductor photocathode 1 includes: a transparent substrate 11; a first electrode 13, formed on the transparent substrate 11 and enabling passage of light that has been transmitted through the transparent substrate 11; a window layer 14, formed on the first electrode 13 and formed of a semiconductor material with a thickness of no less than 10 nm and no more than 200 nm; a light absorbing layer 15, formed on the window layer 14, formed of a semiconductor material that is lattice matched to the window layer 14, is narrower in energy band gap than the window layer 14, and in which photoelectrons are excited in response to the incidence of light; an electron emission layer 16, formed on the light absorbing layer 15, formed of a semiconductor material that is lattice matched to the light absorbing layer 15, and emitting the photoelectrons excited in the light absorbing layer 15 to the exterior from a surface; and a second electrode 18, formed on the electron emission layer.
摘要:
A semiconductor photocathode 1 includes: a transparent substrate 11; a first electrode 13, formed on the transparent substrate 11 and enabling passage of light that has been transmitted through the transparent substrate 11; a window layer 14, formed on the first electrode 13 and formed of a semiconductor material with a thickness of no less than 10 nm and no more than 200 nm; a light absorbing layer 15, formed on the window layer 14, formed of a semiconductor material that is lattice matched to the window layer 14, is narrower in energy band gap than the window layer 14, and in which photoelectrons are excited in response to the incidence of light; an electron emission layer 16, formed on the light absorbing layer 15, formed of a semiconductor material that is lattice matched to the light absorbing layer 15, and emitting the photoelectrons excited in the light absorbing layer 15 to the exterior from a surface; and a second electrode 18, formed on the electron emission layer.
摘要:
Provided are a photocathode plate capable of stably achieving a high sensitive property, and an electron tube using such a photocathode plate.In a photomultiplier tube 1, an insulating layer 63 is formed between a semiconductor electron emission layer 51 in a photocathode plate 23A, and a first electrode 65 electrically connected to an electron releasing portion 59. This insulating layer 63 permits the photocathode plate 23A to be cleaned by heat cleaning at a high temperature, in a stage before formation of an active layer 61 on an exposed region of the semiconductor electron emission layer 51 in the electron releasing portion 59. This makes it feasible to effectively clean the exposed region of the semiconductor electron emission layer 51 in the electron releasing portion 59 and to stabilize the physical properties of the exposed region. In consequence, a higher sensitive property can be stably achieved in the photocathode plate 23A and in the photomultiplier tube 1 using the photocathode plate 23A.
摘要:
Provided are a photocathode plate capable of stably achieving a high sensitive property, and an electron tube using such a photocathode plate. In a photomultiplier tube 1, an insulating layer 63 is formed between a semiconductor electron emission layer 51 in a photocathode plate 23A, and a first electrode 65 electrically connected to an electron releasing portion 59. This insulating layer 63 permits the photocathode plate 23A to be cleaned by heat cleaning at a high temperature, in a stage before formation of an active layer 61 on an exposed region of the semiconductor electron emission layer 51 in the electron releasing portion 59. This makes it feasible to effectively clean the exposed region of the semiconductor electron emission layer 51 in the electron releasing portion 59 and to stabilize the physical properties of the exposed region. In consequence, a higher sensitive property can be stably achieved in the photocathode plate 23A and in the photomultiplier tube 1 using the photocathode plate 23A.
摘要:
The invention relates to a photocathode having a structure that permits a decrease in the radiant sensitivity at low temperatures is suppressed so that the S/N ratio is improved. In the photocathode, a light absorbing layer is formed on the upper layer of a substrate. An electron emitting layer is formed on the upper layer of the light absorbing layer. A contact layer having a striped-shape is formed on the upper layer of the electron emitting layer. A surface electrode composed of metal is formed on the surface of the contact layer. The interval between bars in the contact layer is adjusted so as to become 0.2 μm or more but 2 μm or less.
摘要:
The invention relates to a photocathode having a structure that permits a decrease in the radiant sensitivity at low temperatures is suppressed so that the S/N ratio is improved. In the photocathode, a light absorbing layer is formed on the upper layer of a substrate. An electron emitting layer is formed on the upper layer of the light absorbing layer. A contact layer having a striped-shape is formed on the upper layer of the electron emitting layer. A surface electrode composed of metal is formed on the surface of the contact layer. The interval between bars in the contact layer is adjusted so as to become 0.2 μm or more but 2 μm or less.
摘要:
The invention relates to a photocathode having a structure that permits a decrease in the radiant sensitivity at low temperatures is suppressed so that the S/N ratio is improved. In the photocathode, a light absorbing layer is formed on the upper layer of a substrate. An electron emitting layer is formed on the upper layer of the light absorbing layer. A contact layer having a striped-shape is formed on the upper layer of the electron emitting layer. A surface electrode composed of metal is formed on the surface of the contact layer. The interval between bars in the contact layer is adjusted so as to become 0.2 μm or more but 2 μm or less.
摘要:
A semiconductor photocathode has first and second III-V compound semiconductor layers doped with a p-type impurity and joined to each other to make a heterojunction. The second III-V compound semiconductor layer functions as a light absorbing layer, an energy gap of the second III-V compound semiconductor layer is smaller than that of the first III-V compound semiconductor layer, and Be or C is used as the p-type dopant in each semiconductor layer. At this time, the second III-V compound semiconductor layer may be deposited on the first III-V compound semiconductor layer. The first III-V compound semiconductor layer and the second III-V compound semiconductor layer may contain at least one from each group of (In, Ga, Al) and (As, P, N).
摘要:
A semiconductor device has first and second III-V compound semiconductor layers one of which functions as a photosensitive layer or as a light emitting layer, which are doped with a p-type impurity in a low concentration, and which are joined to each other to make a heterojunction. An energy gap of the second III-V compound semiconductor layer is smaller than that of the first III-V compound semiconductor layer and the p-type dopant in each semiconductor layer is Be or C. At this time, the second III-V compound semiconductor layer may be deposited on the first III-V compound semiconductor layer. The first III-V compound semiconductor layer and the second III-V compound semiconductor layer may contain at least one from each group of (In, Ga, Al) and (As, P, N).