Abstract: Disclosed is an multi-layered SOI substrate, which includes a supporting substrate, and a first insulator, a semiconductor film, a second insulator and a single crystalline semiconductor film (SOI film) which are layered on the main surface of the supporting substrate. The SOI substrate is formed by a direct bonding technique, and a bipolar transistor and an MOS transistor are formed using the single crystalline semiconductor film (SOI layer). The extremely shallow junction can be formed without epitaxial growth, thereby significantly increasing the operation speed of the semiconductor device at a low cost.

Abstract: An optical receiver generates a voltage signal having a predetermined swing from a current signal, and feeds the voltage signal to a decision circuit. An optical receiving element receives the input optical signal, converts the optical signal to a current signal, and provides the current signal to a preamplifier, which converts the input current signal into a voltage signal. The voltage signal is input to an amplifier having a limiting function, which linearly amplifies the voltage signal when the swing of the voltage signal is smaller than a predetermined value, and limitedly amplifies the voltage signal when the voltage signal is greater than the predetermined value. An automatic-gain-control amplifier receives the output from the amplifier with the limiting function, and amplifies the input voltage signal to a voltage signal having a constant swing.

Abstract: A bipolar transistor according to the invention is provided with structure that an intrinsic base made of single crystal Si—Ge and a base leading-out electrode are connected via a link base made of polycrystal Si—Ge by doping at high concentration, further, a part immediately under the intrinsic base has the same conductive type as that of a collector and in a peripheral part, a single crystal Si—Ge layer having the same conductive type as that of a base is provided between the intrinsic base and a collector layer. Hereby, the reduction of the resistance of the link base between the intrinsic base and the base leading-out electrode and the reduction of capacitance between the collector and the base are simultaneously realized, and a self-aligned bipolar transistor wherein capacitance between an emitter and the base and capacitance between the collector and the base are respectively small, power consumption is small and high speed operation is enabled is acquired.

Abstract: Disclosed is an multi-layered SOI substrate, which includes a supporting substrate, and a first insulator, a semiconductor film, a second insulator and a single crystalline semiconductor film (SOI film) which are layered on the main surface of the supporting substrate The SOI substrate is formed by a direct bonding technique, and a bipolar transistor and an MOS transistor are formed using the single crystalline semiconductor film (SOI layer). The extremely shallow junction can be formed without epitaxial growth, thereby significantly increasing the operation speed of the semiconductor device at a low cost.

Abstract: A self-aligned bipolar transistor which has a small base resistance and small emitter-base and collector-base capacitances and is operable at high speed is disclosed. This bipolar transistor is characterized in that a low concentration collector region made of single crystal Si--Ge is self-alignedly formed between an intrinsic base of single crystal Si--Ge and an intrinsic base, and that an extrinsic base electrode and an intrinsic base are connected only through a doped external base. With this arrangement, an energy barrier is not established at the collector base interface owing to the formation of the low concentration region of single crystal Si--Ge, so that the transit time of the carriers charged from the emitter is shortened. The connection between the intrinsic base and the extrinsic base electrode via the doped external base results in the reduction of the base resistance.

Abstract: 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.

Abstract: Disclosed is an multi-layered SOI substrate, which includes a supporting substrate, and a first insulator, a semiconductor film, a second insulator and a single crystalline semiconductor film (SOI film) which are layered on the main surface of the supporting substrate. The SOI substrate is formed by a direct bonding technique, and a bipolar transistor and an MOS transistor are formed using the single crystalline semiconductor film (SOI layer). The extremely shallow junction can be formed without epitaxial growth, thereby significantly increasing the operation speed of the semiconductor device at a low cost.

Abstract: A transistor is formed on a bonded SOI substrate. A collector electrode is connected to the peripheral sides of the collector areas on the insulator. A first insulator of isolation is formed on the peripheral side of the collector electrode. A base electrode is connected to a base area on the first insulator of isolation. Second insulators of isolation are formed on the peripheral side of a base electrode, and emitter electrode is connected to an emitter area by the second insulators of isolation. The connections between the collector electrode and the collector areas, between the base electrode and the base area, and between the emitter electrode and the emitter area are made under the emitter electrode, so the occupation area is small.

Abstract: A semiconductor device has an electrically insulating substrate and a semiconductor layer formed on the insulating substrate. A plurality of semiconductor regions are defined so as to be joined to each other to form at least two homojunctions in the semiconductor layer. A lead conductor for one of the semiconductor regions which is required to have a small thickness has a specific structure such that the lead conductor is in contact with the one semiconductor region at the main surface of the semiconductor layer for electrical connection therebetween and extends over that portion of the semiconductor layer which contributes to definition of at least one of the semiconductor regions other than the first-mentioned one semiconductor region.

Abstract: A first region of a first conductivity type is formed in the surface of a semiconductor body, and second and third regions of a second conductivity type are formed on and under, respectively, of the first region. An electrode region formed on a first insulating film formed on the semiconductor body is connected electrically to the first region. The electrode region is defined as having an elongated first part an upper surface of which is connected to an electrode, and having a second, different part which has a substantially constant width and which width is substantially equal to the thickness of the first portion of the electrode region. A metal silicide film is formed over the upper surface of the first portion of the electrode region. The first, second and third regions can be base, emitter and collector regions, respectively, of a bipolar transistor formed in an island region of an epitaxially grown layer on a semiconductor substrate.

Abstract: A vertical bipolar transistor arrangement in which the distance between the emitter and the isolation region is kept within a range determined by the sum of emitter depth and base width (i.e., the thickness of the base in the depth direction). This keeps the carriers given by the emitter from getting trapped inside, thereby preventing the cut-off frequency from dropping.

Abstract: A vertical bipolar transistor arrangement in which the distance between the emitter and the isolation region is kept within a range determined by the sum of emitter depth and base width (i.e., the thickness of the base in the depth direction). This keeps the carriers given by the emitter from getting trapped inside, thereby preventing the cut-off frequency from dropping.

Abstract: A high integration bipolar transistor operable at very high operating speed is disclosed. A semiconductor device of this invention has a semiconductor substrate of a first conductivity type, a buried impurity region formed on the substrate, and a bipolar transistor formed on the buried impurity region, wherein a plurality of monocrystalline active regions defined by the buried impurity region are isolated from each other by an element isolation insulator, the buried impurity region is connected to a graft region formed on the element isolation insulator at least at the side wall of the buried impurity region, and connected to a semiconductor element in a different active region via the graft region.

Abstract: A semiconductor device is disclosed, which includes bipolar transistor each having an emitter, base and collector formed inside each protruding portion of a semiconductor substrate, and trenches for device isolation. The bipolar transistor and the trench are spaced apart from each other by a predetermined spacing. According to this arrangement, the width of a base contact becomes uniform and any change of transistor characteristics can be prevented effectively.

Abstract: A bipolar transistor capable of operating at high speeds. In a bipolar transistor designed for operation at high speeds, a polycrystalline silicon layer used as a base electrode effects is a contact area with respect to the base region which lacks precision or tends to increase. Further, when the transistor is formed in a small size, the ratio of the contact area with respect to the polycrystalline area increases, making it difficult to increase the operation speed. In order to reduce the contact area of the polycrystalline silicon layer, this invention deals with the structure in which the polycrystalline silicon layer is brought into contact with a portion near the edge of the convex semiconductor layer maintaining a small size and a high precision.

Abstract: A logic circuit is provided which includes a first multi-emitter transistor with its emitters coupled to a group of first input lines and a first transistor with its base coupled to the collector of said first multi-emitter transistor. A second transistor is also provided with its base coupled to the collector of said first transistor, said second transistor having a polarity opposite to that of said first multi-emitter transistor. A second multi-emitter transistor is connected with its base coupled to the collector of said second transistor and with its emitters coupled to a group of second input lines, and a third transistor is connected with its base coupled to the collector of said second multi-emitter transistor and with its collector coupled to an output line. The collector of said first multi-emitter transistor is coupled to the emitter of said second multi-emitter transistor in order to absorb minority carriers stored in the transistors. This feature significantly improves the circuit operating speed.

Abstract: A semiconductor integrated circuit device incorporating bipolar transistors and IILs comprises respective buried layers in a substrate and active regions. A buried layer formed in the IIL region has a larger Gummel number than that of a buried layer formed in the bipolar transistor region so that a leakage current to the substrate is prevented. A larger Gummel number of the buried layer is accomplished by increasing the impurity concentration or the thickness of the layer. The device structure allows an enhanced circuit packing density, while suppressing a leakage current to the substrate.