Abstract: The invention is directed to providing a technique for increasing a hold voltage of an electrostatic breakdown protection device having a bipolar transistor structure more than conventional and reducing the size of the device. A base region (a P impurity layer) is formed on a front surface of an epitaxial layer, an emitter region (an N+ impurity layer) is formed on the front surface of the P impurity layer, and the epitaxial layer and an N+ impurity layer form a collector region. A connected portion of a base electrode and the base region (the P impurity layer) is located between the end of the base region (the P impurity layer) on a collector electrode side and the emitter region (the N+ impurity layer). It means that the electrodes for the collector, the base and the emitter are formed in this order. The base electrode and the emitter electrode are connected through a wiring (not shown). A P+ isolation layer for dividing the epitaxial layer into a plurality of island regions is further formed.

Abstract: The invention provides a semiconductor integrated circuit preventing an electrostatic breakdown due to a surge voltage applied to a power supply wiring or a ground wiring and preventing noise interference between a digital circuit and an analog circuit. By providing a first electrostatic breakdown protection diode and a first electrostatic breakdown protection bipolar transistor in a first island region, the first electrostatic breakdown protection diode and the first electrostatic breakdown protection bipolar transistor turn on when a surge voltage is applied to a first ground wiring and protect a digital circuit against an electrostatic breakdown. Furthermore, a first isolation layer is contacted with the first ground wiring in a position that is more adjacent to a first ground pad than the digital circuit, and a second isolation layer is contacted with a second ground wiring in a position that is more adjacent to a second ground pad than an analog circuit.

Abstract: The invention provides a semiconductor integrated circuit preventing an electrostatic breakdown due to a surge voltage applied to a power supply wiring or a ground wiring and preventing noise interference between a digital circuit and an analog circuit. By providing a first electrostatic breakdown protection diode and a first electrostatic breakdown protection bipolar transistor in a first island region, the first electrostatic breakdown protection diode and the first electrostatic breakdown protection bipolar transistor turn on when a surge voltage is applied to a first ground wiring and protect a digital circuit against an electrostatic breakdown. Furthermore, a first isolation layer is contacted with the first ground wiring in a position that is more adjacent to a first ground pad than the digital circuit, and a second isolation layer is contacted with a second ground wiring in a position that is more adjacent to a second ground pad than an analog circuit.

Abstract: The invention is directed to providing a technique for increasing a hold voltage of an electrostatic breakdown protection device having a bipolar transistor structure more than conventional and reducing the size of the device. A base region (a P impurity layer) is formed on a front surface of an epitaxial layer, an emitter region (an N+ impurity layer) is formed on the front surface of the P impurity layer, and the epitaxial layer and an N+ impurity layer form a collector region. A connected portion of a base electrode and the base region (the P impurity layer) is located between the end of the base region (the P impurity layer) on a collector electrode side and the emitter region (the N+ impurity layer). It means that the electrodes for the collector, the base and the emitter are formed in this order. The base electrode and the emitter electrode are connected through a wiring (not shown). A P+ isolation layer for dividing the epitaxial layer into a plurality of island regions is further formed.

Abstract: An air cleaning filter having a carrier made of activated carbon fibers in the form of a web which supports at least one kind of chemical agent selected from the group consisting of (a) an alkali agent selected from a hydroxide or carbonate or an alkali metal, (b) an acidifying agent selected from acid aluminum phosphate or phosphoric acid, and (c) an oxidizing agent composed of two compounds, i.e. active manganese dioxide resulting from an alkali permanganate and an alkali iodate, or which supports combined chemicals of (a) the alkali agent and (c) the oxidizing agent, or combined chemicals of (b) the acidifying agent and (c) the oxidizing agent, wherein one or both surfaces of the web are covered with a nonwoven fabric to make an integrated filter.