摘要:
This invention discloses a heterojunction type field effect transistor such as 2DEG-FET and a heterojunction type bipolar transistor such as 2DEG-HBT. The former is fabricated by applying to the formation of its source and drain regions a technique which causes the disorder of the heterojunction by intoduction of an impurity such as by ion implantation or a technique which causes the disorder of the heterojunction by forming a film made of at least one kind of material selected from insulators, metals and semiconductors which have a different linear coefficient of thermal expansion from that of the material of a semiconductor substrate on the heterojunction semiconductor region which is to be disordered. The latter is fabricated by applying either of the techniques described above to a base ohmic contact region. These semiconductor devices can reduce the source-gate resistance and the parasitic base resistance. The invention discloses also the structure of the ohmic contact layer which has a trench on the surface thereof and is particularly effective for reducing the source-gate parasitic resistance.
摘要:
A solid film forming apparatus, e.g., an MO-MBE (Metal-Organic Molecular Beam Epitaxy) apparatus, wherein evacuatable containers isolated from a growth chamber by a switching device and connected to raw material gas introduction pipings are provided between the growth chamber for a solid film, e.g., a compound semiconductor, and raw material gas introduction pipings. Growth of the solid film is controlled by opening and closing the switching device and evacuating the container at least while the switching device is closed during the growth of the solid film. An undesired influence on the growing film due to residual gas in the containers which are not used for growth can be prevented and, hence, interception and introduction of the raw material gas into the growth chamber can be performed with remarkably high controllability, and films of superior abruptness of the interface between films, e.g., the heterojunction of the compound semiconductor, can be obtained.
摘要:
An optical waveguide comprising a layer formed on a substrate, having a mixed composition of silicon oxide and silicon nitride and having an arbitrary value of refractive index ranging between those of the silicon oxide and the silicon nitride. The layer of said mixed composition can be formed on the substrate to easily fabricate the optical waveguide of the present invention by conducting a sputtering method employing a Si target and controlling the composition of a sputtering gas composed of a mixture of N.sub.2 and O.sub.2 gases.
摘要:
The present invention relates to a semiconductor laser which oscillates in a single longitudinal mode and with a low threshold current and which exhibits a good mode stability against reflected light, and provides a structure of a distributed feedback semiconductor laser with modulation for a gain. The structure is such that gain producing regions are periodically arranged and that a substance transparent to laser radiation is buried between the regions. A layer including the gain regions is formed of a superlattice layer, and an impurity is diffused or implanted into periodic positions of the layer, whereby the transparent regions and the gain regions with little lattice damages can be readily formed.
摘要:
Semiconductor surface emitting elements having a plurality of wavelengths being manufactured on a signal substrate through MOVPE selective growth. More specifically, provided is a semiconductor light emitting element array which comprises; a semiconductor crystal substrate; an insulating film disposed on a surface of the substrate, the insulating film being divided into two or more regions, each of which having two or more openings exposing the surface of the substrate; semiconductor rods extending from the surface of the substrate upward through the openings, the semiconductor rods each having an n-type semiconductor layer and a p-type semiconductor layer being laminated in its extending direction, thereby providing a p-n junction; a first electrode connected to the semiconductor crystal substrate; and a second electrode connected to upper portions of the semiconductor rods; wherein the heights of the semiconductor rods as measured from the substrate surface vary by each of the two or more regions.
摘要:
It is an object of the present invention to provide a semiconductor light emitting device capable of securing, in use of an optical information processing or an optical communication system, a low threshold and high efficiency operation as well as a high output characteristic. An active layer structure having a flatness and an interface acuteness of a quantum well structure improved by introducing a multi-period super lattice structure between a substrate for crystal growth and a light emitting layer area further to on a misoriented substrate sued to enhance a homogeneity of a semiconductor crystal. Further, a carrier confinement and a light confinement can be enhanced by providing a margin for design of the quantum well structure. According to the present invention, it is possible to realize a semiconductor laser element which can improve, as compared with a semiconductor laser device to which the present process is not applied, a threshold current and a slope efficiency, and which can achieve, as compared with an element not provided with a window structure, a high output characteristic with a maximum optical output enhanced.
摘要:
A field-effect transistor or a bipolar transistor may be provided in which the contact resistance between a channel layer or base layer and a contact layer are reduced. For example, an InGaAs buffer layer may be formed on the substrate side of an InGaAs channel layer of a field-effect transistor and by the bypassing effect that carriers pass through this InGaAs buffer layer, the InGaAs channel layer comes in contact with the contact layer with a low resistance. The contact resistance between the InGaAs channel layer and the contact layer can be reduced to 10 ohm per a width of 10.mu.m, and as a result, the value of transconductance factor K of a field-effect transistor can be increased in 14 mA/V.sup.2 per a width of 10.mu.m.
摘要:
The present invention provides a waveguide type optical switch which has a high extinction ratio and can be driven efficiently at a low voltage or a low current injection. Where the waveguide type optical switch is used as a reflection type optical switch, the switch section is of current confinement structure, and where it is used as a directional coupler type optical switch, the pn junction is formed in the position where the optical electric field takes the maximum value for the fundamental mode of the light propagating in the waveguide.
摘要:
When a semiconductor device is produced by growing epitaxially a compound semiconductor layer on a Si or Ge substrate, lattice matching between the substrate crystal and the compound semiconductor layer to be formed on the substrate can be improved by ion-implanting an ion species element, which increases the lattice constant of Si or Ge as the substrate, into the Si or Ge substrate in order to increase its lattice constant. In comparison with conventional semiconductor devices using Si or Ge into which ion implantation is not made, the semiconductor device produced by the method described above can improve remarkably its characteristics. In the case of a semiconductor laser device, for example, its threshold value drops drastically and its service life can be prolonged remarkably.
摘要:
To provide a solar cell enabling practical electric power to be obtained and excitons to be effectively collected, and a manufacturing method of the solar cell. A nanowire solar cell 1 comprises: a semiconductor substrate 2; a plurality of nanowire semiconductors 4 and 5 forming pn junctions; a transparent insulating material 6 filled in the gap between the plurality of nanowire semiconductors 4 and 5; an electrode 7 covering the end portion of the plurality of nanowire semiconductors 4 and 5; and a passivation layer 10 provided between the semiconductor 5 and the transparent insulating material 6 and between the semiconductor 5 and the electrode 7.