Abstract: The main purpose is to provide a semiconductor device which has a field plate wherein the electric field concentration at a step part can be eliminated and a higher withstanding voltage can be gained.

Abstract: In a high breakdown voltage semiconductor device, a buried diffusion region is formed on a semiconductor substrate and an epitaxial layer is formed on the buried diffusion region and the substrate. The epitaxial layer includes a low breakdown voltage element region adjoined by a high breakdown voltage isolation region. A method for forming the high breakdown voltage isolation region complies with a Resurf condition by adjusting a thickness and an impurity concentration of the epitaxial layer. Thus, a high breakdown voltage semiconductor device and a manufacturing process therefor is provided, which includes a low breakdown voltage element region and a high breakdown voltage element region, and a high breakdown isolation region separates a high breakdown voltage region without impairing the characteristics of an element formed on the low breakdown voltage element region.

Abstract: A gate electrode layer is formed opposite to a p type backgate region posed between an n type source region and an n type epitaxial region, with a gate insulating layer interposed therebetween. A sidewall insulating layer is formed to cover a sidewall of the gate electrode layer. A p type backgate region has a relatively shallow p type diffusion region and a relatively deep p type diffusion region. The relatively deep p type diffusion region has a portion overlapping the relatively shallow p type diffusion region, and has its end portion at the substrate surface located directly beneath the sidewall insulating layer. Accordingly, a semiconductor device and a manufacturing method thereof that allow easy control of the threshold voltage of a DMOS transistor and facilitate realization of a rapidly operating bipolar transistor are attained.

Abstract: An n− epitaxial layer serving as a collector region is formed on a p-type silicon substrate. A p diffusion layer serving as a base region is formed on the n− epitaxial layer. An n− diffusion layer and an n+ diffusion layer defining an emitter region are formed on the p diffusion layer. A p+ diffusion layer serving as a base contact region for attaining contact with the p diffusion layer is formed with a prescribed interval between the same and the emitter region. Thus obtained is a semiconductor device comprising a transistor suppressing dispersion of a current amplification factor.

Abstract: The present invention aims to provide a semiconductor device in which a satisfactory breakdown voltage can be obtained without increasing its chip size, and a method of manufacturing the same. A first electrode layer and a second electrode layer are formed. An inorganic type silicon oxide film is formed so as to cover first and second electrodes. An organic type silicon oxide film is formed on a surface of inorganic type silicon oxide film above a portion of a surface of first electrode layer. At a region of inorganic type silicon oxide film where organic type silicon oxide film is not formed, a through hole is formed, exposing a portion of a surface of second electrode layer. An interconnection layer is formed so as to be in contact with second electrode layer via through hole and opposing first electrode layer with inorganic and organic type silicon oxide films therebetween.

Abstract: A semiconductor device which has few peripheral element malfunctions and superior performance is obtained. The semiconductor device includes a p-type buried layer on a main surface of a semiconductor substrate, an n-type cathode region provided on the p-type buried layer, and a p-type anode region in contact with the side surface of the n-type cathode region, the p-type buried layer being higher than the p-type anode region in acceptor content, and the p-type buried layer being in contact with the bottom surfaces of the anode and cathode regions.

Abstract: In a semiconductor device and a method of manufacturing the same according to the invention, a p-type diffusion region for electrically connecting a back gate region and an electrode layer together is formed at a source region. Thereby, both of source region and p-type diffusion region are electrically connected to the electrode layer, so that the source region and the back gate region are maintained at the same potential. As a result, it is possible to provide the semiconductor device and the method of manufacturing the same which can suppress operation of a parasitic bipolar transistor formed in the semiconductor device even if a gate electrode has a large width.

Abstract: A semiconductor device which contains an electrode or an interconnection subjected to a high voltage prevents current leakage due to polarization of a mold resin. In this semiconductor device, a glass coat film 13a covering a semiconductor element has an electrical conductivity in a range defined by the following formula (1) under the conditions of temperature between 17.degree. C. and 145.degree. C.:conductivity.gtoreq.1.times.10.sup.-10 /E (1)(E: an electric field intensity ?V/cm!, E.gtoreq.2.times.10.sup.4 ?V/cm!)Owing to employment of the electrically conductive glass coat film, an electron current flowing through the conductive glass coat film suppresses an electric field caused by polarization of a mold resin.

Abstract: A resurf structure is provided which includes an n type diffusion region surrounded by a n- diffusion region, in which a part of the joined combination of the n type diffusion region and the n- diffusion region is separated by a narrow p- substrate region in between. An aluminum lead is provided between the separated n- diffusion regions, and a signal is level shifted. A high voltage semiconductor device which includes a small area high voltage isolation region is obtained without process cost increase.

Abstract: A high breakdown voltage pch-MOSFET having a breakdown voltage of 150V or more and a control element controlling the same are formed in a common n.sup.- epitaxial layer. Only an n-type region of n.sup.- epitaxial layer is distributed at a region located between the high breakdown voltage pch-MOSFET and the control element and extending along the substrate surface. A semiconductor device thus formed achieves a good throughput and reduces a required chip area.

Abstract: A high breakdown voltage pch-MOSFET having a breakdown voltage of 150 V or more and a control element controlling the same are formed in a common n.sup.- epitaxial layer. Only an n-type region of n.sup.- epitaxial layer is distributed at a region located between the high breakdown voltage pch-MOSFET and the control element and extending along the substrate surface. A semiconductor device thus formed achieves a good throughput and reduces a required chip area.

Abstract: In a semiconductor device and a method of manufacturing the same according to the invention, a p-type diffusion region for electrically connecting a back gate region and an electrode layer together is formed at a source region. Thereby, both of source region and p-type diffusion region are electrically connected to the electrode layer, so that the source region and the back gate region are maintained at the same potential. As a result, it is possible to provide the semiconductor device and the method of manufacturing the same which can suppress operation of a parasitic bipolar transistor formed in the semiconductor device even if a gate electrode has a large width.

Abstract: A semiconductor device which contains an electrode or an interconnection subjected to a high voltage prevents current leakage due to polarization of a mold resin. In this semiconductor device, a glass coat film 13a covering a semiconductor element has an electrical conductivity in a range defined by the following formula (1) under the conditions of temperature between 17.degree. C. and 145.degree. C.:conductivity.gtoreq.1.times.10.sup.-10 /E . . . (1)(E: an electric field intensity ?V/cm!, E.gtoreq.2.times.10.sup.4 ?V/cm!)Owing to employment of the electrically conductive glass coat film, an electron current flowing through the conductive glass coat film suppresses an electric field caused by polarization of a mold resin.

Abstract: A semiconductor device having a voltage sensing element is disclosed which allows reduction of power consumption in comparison with a conventional device and enables to obtain a sufficient output voltage to secure sensing accuracy even when an input voltage is small. In the voltage sensing element of the semiconductor device, an n.sup.- layer is formed on a front surface of a p.sup.- substrate. A p type diffused region and an n type diffused region are formed at a main surface of n.sup.- layer, spaced apart by a prescribed distance. An electrode is formed on p type diffused region, and an electrode is formed on n type diffused region. An electrode is formed on a rear surface of p.sup.- substrate. P.sup.- substrate and n.sup.- layer constitute a diode in a reversely biased state. As a result, power consumption is reduced in comparison with a conventional voltage dividing resistor circuit.

Abstract: A low concentration impurity region 6 of a second conductivity type is formed to cover lower portion of a high concentration impurity region 8 of the second conductivity type. Consequently, impurity concentration gradient between the high concentration impurity region 8 of the second conductivity type and the low concentration impurity layer 2 of a first conductivity type can be made moderate to relax the electric field, which leads to provision of higher breakdown voltage of the semiconductor device. Further, the depth of impurity diffusion of the low concentration impurity region 6 of the second conductivity type from the main surface of the low concentration impurity layer 2 of the first conductivity type is made at least three times the depth of impurity diffusion of the high concentration impurity region 8 of the second conductivity type from the main surface of the low concentration impurity layer 2 of the first conductivity type.

Abstract: A high-breakdown voltage semiconductor device and a fabrication method are disclosed. A dielectric layer (3) dielectrically isolates a semiconductor substrate (1) from a n.sup.- type semiconductor layer (2). An n.sup.+ type semiconductor region (4) having a lower resistance than the n.sup.- type semiconductor layer (2) is formed as if surrounded by a p.sup.+ type semiconductor region (5). The dielectric layer (3) consists of a relatively thick first region (3a) and a relatively thin first region (3b). The n.sup.+ type semiconductor region (4), which is located above the first region (3a), occupies a narrower area than the first region (3a). Thus, by forming the dielectric layer thick immediately under the first semiconductor layer and controlling the thickness of the dielectric layer at other portions, the breakdown voltage of the semiconductor device is improved without curbing RESURF effect.

Abstract: In a semiconductor device having a low ON resistance, an n.sup.- -type epitaxial layer (1) is formed on an upper surface of an n.sup.+ -type substrate (8) and p-type diffusion regions (2) are selectively formed on its upper surface, while n-type diffusion regions (3) are further formed on upper surfaces thereof. A gate electrode (5) wrapped up in an oxide film (4) is provided on the upper surface of the n.sup.- -type epitaxial layer (1) and above portions of the p-type diffusion regions (2) held between the n.sup.- -type epitaxial layer (1) and the n.sup.+ -type diffusion regions (3). Grooves (9) are formed in the upper surface of the n.sup.- -type epitaxial layer (1) located under a gate electrode (5) to extend perpendicularly to junction planes between the n.sup.- -type epitaxial layer (1) and the p-type diffusion regions (2).

Abstract: A semiconductor device having a voltage sensing element is disclosed which allows reduction of power consumption in comparison with a conventional device and enables to obtain a sufficient output voltage to secure sensing accuracy even when an input voltage is small. In the voltage sensing element of the semiconductor device, an n.sup.- layer is formed on a front surface of a p.sup.- substrate. A p type diffused region and an n type diffused region are formed at a main surface of n.sup.- layer, spaced apart by a prescribed distance. An electrode is formed on p type diffused region, and an electrode is formed on n type diffused region. An electrode is formed on a rear surface of p.sup.- substrate. P.sup.- substrate and n.sup.- layer constitute a diode in a reversely biased state. As a result, power consumption is reduced in comparison with a conventional voltage dividing resistor circuit.

Abstract: In this semiconductor device, first, fifth and fourth impurity regions of a second conductivity type are formed on a main surface of a semiconductor layer of a first conductivity type with a predetermined space between each other. Second and third impurity regions of the first conductivity type are formed on the main surface of the first impurity region with a predetermined space between each other. A second gate electrode is formed between the second and third impurity regions. A first gate electrode is formed between the third impurity region and the semiconductor layer. A cathode electrode is connected to the third impurity region, and a short-circuit electrode is connected to first and second impurity regions. The first and fifth impurity regions are electrically short-circuited.

Abstract: A low concentration impurity region 6 of a second conductivity type is formed to cover lower portion of a high concentration impurity region 8 of the second conductivity type. Consequently, impurity concentration gradient between the high concentration impurity region 8 of the second conductivity type and the low concentration impurity layer 2 of a first conductivity type can be made moderate to relax the electric field, which leads to provision of higher breakdown voltage of the semiconductor device. Further, the depth of impurity diffusion of the low concentration impurity region 6 of the second conductivity type from the main surface of the low concentration impurity layer 2 of the first conductivity type is made at least three times the depth of impurity diffusion of the high concentration impurity region 8 of the second conductivity type from the main surface of the low concentration impurity layer 2 of the first conductivity type.