摘要:
The present invention relates to a contact structure not only for a semiconductor device having a hetero-junction bipolar transistor or a hetero-insulated gate field effect transistor but also for semiconductor devices at large. In a semiconductor layer of a polycrystalline or amorphous undoped III-V compound semiconductor or an alloy thereof, a through hole is formed for contact. The size of the through hole is set to permit exposure of at least part of a first conductor layer and a dielectric layer, such as an Si compound, present around the first conductor layer, and a second conductor layer is formed within the through hole so as to contact the first conductor layer. Since the semiconductor layer can be subjected to a selective dry etching for the dielectric layer, the dielectric layer is not etched at the time of forming the above through hole in the semiconductor layer. As a result an electric short-circuit of the second conductor layer with a single crystal semiconductor layer which underlies the dielectric layer can be prevented.
摘要:
A method for fabricating a semiconductor device comprises the steps of forming the first semiconductor layer on a semiconductor substrate, forming a surface protection layer of antimony (Sb) or the material having Sb as its main component, executing the other steps necessary for the fabrication of the semiconductor device, removing the surface protection layer, and forming, on the first semiconductor layer thus exposed, the second semiconductor layer.
摘要:
Disclosed is a semiconductor device using a polycrystalline compound semiconductor with a low resistance as a low resistance layer, and its fabrication method. The above polycrystalline compound semiconductor layer is doped with C or Be as impurities in a large amount, and is extremely low in resistance. The polycrystalline compound semiconductor layer is formed by either of a molecular beam epitaxy method, an organometallic vapor phase epitaxy method and an organometallic molecular beam epitaxy method under the condition that a substrate temperature is 450.degree. C. or less and the ratio of partial pressure of a V-group element to a III-group element is 50 or more. In the case that the above polycrystaline compound semiconductor layer with a low resistance is used as an extrinsic base region of an heterojunction bipolar transistor, since the extrinsic base region can be formed on a dielectric film formed on a collector, it is possible to reduce the base-collector capacitance, and hence to enhance the operational speed of the heterojunction bipolar transistor.
摘要:
A hetero-junction bipolar transistor having an emitter composed of a semiconductor having a wider forbidden band width than that of a semiconductor constituting a base is disclosed. In the transistor, the emitter and the electrode leader area composed of a single crystalline semiconductor are provided being extended from the upper part of the emitter to the surface of the base through an insulating layer, for the purpose of making it possible to miniaturize the transistor and to operate the transistor at a high-speed by decreasing the emitter resistance.
摘要:
A hetero junction bipolar transistor provides a contact area an area between an emitter (or collector) electrode and a wiring formed on the electrode that is larger than that of the emitter (or collector). A variation in voltage applied to an emitter (or collector)-base junctions is prevented and a stable operation of the transistor is attained. In addition, when an etching operation is carried out, an insulation film is formed on a side part of a mask. A patterning of the emitter (or collector) is then carried out and thus an emitter (or collector) having a size approximate to that of the mask is formed.
摘要:
A semiconductor device comprises a semiconductor substrate formed by a first single crystalline semiconductor material and semiconductor layers formed on the semiconductor substrate by a second single crystalline semiconductor material doped with an element which can easily surface segregate. The surface of the semiconductor substrate is formed of a crystalline plane substantially equivalent to a facet plane which is formed on the surface of the second single crystalline semiconductor material if the second single crystalline semiconductor material is epitaxially grown with being doped with the element on a (100) plane of the first single crystalline semiconductor material.
摘要:
A blood vessel ultrasonic image measuring method capable of facilitating the positioning of an ultrasonic probe and acquiring sufficient positioning accuracy. Because of inclusion of an around-X-axis positioning step of causing a multiaxis driving device to position an ultrasonic probe such that distances from respective ultrasonic array probes to the center of a blood vessel are equalized, and an X-axis direction positioning step and an around-Z-axis positioning step of causing the multiaxis driving device to position the ultrasonic probe such that the image of the blood vessel is positioned at the center portion in the width direction of the first short axis image display area and the second short axis image display area, the positioning may be performed by using the positions in the longitudinal direction of the ultrasonic array probes relative to the blood vessel or the distances of the ultrasonic array probes to the blood vessel.
摘要:
Provided is a display device in which design properties have been improved by eliminating the flickering when the display level changes. A microcomputer (5) causes light emission of first LEDs (23 and 24) which are the first and second ones counting from the right end among the emitting first LEDs (21 to 24), with decreasing brightness towards the right end. Furthermore, the microcomputer (5) causes light emission of second LEDs from a second LED (77) which is disposed at the right end of the second LEDs (71 to 77), to a second LED (73) which is disposed at a position overlapped with the first LEDs (23 and 24) that emit light with decreasing brightness towards the right end, and also causes light emission of second LEDs (73 and 74), which are the first and second ones counting from the left end among the emitting second LEDs (73 to 77), with decreasing brightness towards the left end.
摘要:
External electrodes are provided on a bottom surface of a laminate, and are connected to both ends of a main line and both ends of a sub-line, respectively. A warpage prevention conductor is provided on an insulating material layer that is provided on a top surface side of the laminate with respect to insulating material layers to which the main line is provided and with respect to insulating material layers to which the sub-line is provided. The warpage prevention conductor overlaps with the external electrodes when seen from a z-axis direction in a plan view. A conductor layer that is not connected to the main line or the sub-line is not provided on any of the insulating material layers provided on a bottom surface side of the laminate with respect to the insulating material layer on which the warpage prevention conductor is provided.
摘要:
The present invention relates to an optical waveguide comprising a lower cladding layer, a patternized core layer and an upper cladding layer, wherein a striking part for positioning is provided in one end part thereof, and an optical path turning mirror face is formed in a position different from a striking part-forming end part in the above core layer.Capable of being provided are an optical waveguide and an optoelectronic circuit board each having a simple configuration in which an optical device is not mounted on an optical wiring part or an optoelectronic composite wiring part and capable of connecting an optical device with a core of an optical waveguide in an optical wiring part (optical waveguide) or an optoelectronic composite wiring part (optoelectronic circuit board) at a high position accuracy and an optical module comprising an optical waveguide or an optoelectronic circuit board and a connector.