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:
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:
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:
The present invention provides a semiconductor device which comprises active components, passive components, wiring lines and electrodes and are satisfactory in terms of mechanical strength, miniaturization and thermal stability. In the semiconductor device, openings are formed just below active components. These openings are filled with conductor layers. Conductor layers are also formed where openings are not formed.
摘要:
In a semiconductor device using an emitter top heterojunction bipolar transistor having a planar shape in a ring-like shape, a structure is provided in which a base electrode is present only on an inner side of a ring-like emitter-base junction region. This allows reduction of base/collector junction capacitance per unit emitter area, whereby a semiconductor device having high power adding efficiency and high power gain suitable for a power amplifier can be realized. Further, in a multistage power amplifier including first and second amplifier circuits each having one or more of bipolar transistors, a bipolar transistor in the first amplifier circuit uses an emitter having a planar shape in a rectangular shape, and a bipolar transistor in the second amplifier circuit uses an emitter having a ring-like shape and a base electrode only on the inner side of the emitter.
摘要:
The present invention provides a method of manufacturing semiconductor devices, by which InGaAs-base C-top HBTs are manufactured at low cost. Helium ions with a smaller radius are implanted into a p-type InGaAs layer (in external base regions) not covered with a lamination consisting of an undoped InGaAs spacer layer, n-type InP collector layer, n-type InGaAs cap layer, and collector electrode from a direction vertical to the surface of the external base layer or within an angle of 3 degrees off the vertical. In consequence, the p-type InGaAs in the external base regions remains p-type conductive and low resistive and the n-type InAlAs layer in the external emitter regions can be made highly resistive. By this method, InGaAs-base C-top HBTs can be fabricated on a smaller chip at low cost without increase of the number of processes.
摘要:
This invention is intended to provide an HBT capable of achieving, if the HBT is a collector-up HBT, the constriction of the emitter layer disposed directly under an external base layer, and reduction in base-emitter junction capacity, or if the HBT is an emitter-up HBT, reduction in base-collector junction capacity. For the collector-up HBT, window structures around the sidewalls of a collector are used to etch either the emitter layer disposed directly under the external base layer, or an emitter contact layer For the emitter-up HBT, window structures around the sidewalls of an emitter are used to etch either the collector layer disposed directly under the external base layer, or a collector contact layer. In both HBTs, the external base layer is supported by a columnar structure to ensure mechanical strength.
摘要:
The technical subject of the invention is to inhibit disconnection of electrodes caused by a step and bursting caused by residual air. That is, an object of the present invention is to provide a semiconductor device capable of overcoming a drawback due to the shape of a concave portion present in the zinc blende type compound semiconductor substrate in which the area of the bottom is larger than the surface in the cross sectional shape, as well as a manufacturing method thereof. According to the invention, a hole or step present in the semiconductor substrate constituting the semiconductor device is formed into a normal mesa shape irrespective of the orientation of the crystals on the surface of the semiconductor substrate. Accordingly, the present invention uses a novel wet etching solution having an etching rate for a portion below the etching mask higher than that in the direction of the depth of the semiconductor substrate.
摘要:
A semiconductor device capable of overcoming a drawback due to the shape of a concave portion present in the zinc blende type compound semiconductor substrate in which the area of the bottom is larger than the surface in the cross sectional shape, as well as a manufacturing method thereof. A hole or step present in the semiconductor substrate constituting the semiconductor device is formed into a normal mesa shape irrespective of the orientation of the crystals on the surface of the semiconductor substrate. A wet etching solution having an etching rate for a portion below the etching mask higher than that in the direction of the depth of the semiconductor substrate is used.