Origin Electric Company, Limited

Kokusai Electric Co., Ltd.

Ryoji Saito

Toshikazu Karino

Shoichiro Izumi

Yasuhiro Harada

Koji Tometsuka

Tohru Yoshida

Atsushi Nakamura

Makoto Ozawa

Fumihide Ikeda

Shuichi Ushiki

Masaoki Sekine

Mikio Ito

Satoshi Kakizaki

Susumu Teramoto

Mikio Koizumi

Yasuo Kii

Takayuki Taguchi

A switching power supply system comprises a semiconductor switching device for selectively opening and closing a current path from a dc power source to a load, an inductive component connected in series with the switching device, a series combination of a first diode and a voltage clamp, and a control circuit for controlling the switching device. The series combination is connected in parallel to the switching device or the inductive component such as a transformer or an inductor. The first diode has a carrier lifetime equal to or longer than the switching period of the switching device. A discharge circuit is connected between one terminal of the dc power source and a branch point between the first diode and the voltage clamp, and arranged to regulate an amount of energy returned from the voltage clamp to the dc power source.

Switching power supply system and process

In the semiconductor manufacturing apparatus according to the present invention, there are provided a cassette stocker for accommodating wafer cassettes loaded with wafers, a reaction furnace provided with heating means, a reaction gas introducing means for introducing reaction gas into the reaction furnace, a gas discharging means for discharging exhaust gas in the reaction furnace, a boat for supporting wafers, a buffer cassette stocker for storing unprocessed wafers, a boat elevating means for inserting the boat into and retrieving the boat from the reaction furnace, a wafer transfer means for transferring wafers between the boat and the wafer cassette accommodated on the cassette stocker, and a wafer cassette transfer means for transferring wafer cassettes between the buffer cassette stocker and the cassette stocker, and the buffer cassette stocker is enclosed to provide an antioxidation area to prevent natural oxidation of the wafers in standby status.

Semiconductor wafer reaction furnace with wafer transfer means

A resonant forward converter comprises a saturable inductor connected in series to a primary winding of a transformer and a switching device. The saturable inductor has a predetermined value of inductance in a light current region and a small value of inductance at a predetermined integral voltage due to magnetic saturation.

Reduced-resonant-current zero-voltage-switched forward converter using

A high power factor AC/DC converter is disclosed. In the AC/DC converter in which a rectifying circuit RC1 rectifies a commercially available AC power supply Ei, a switching device turns on and off so that the rectified voltage is applied across the primary winding n1 of the transformer Tr1 to provide a high frequency voltage across the secondary winding n2, and the high frequency voltage is rectified by means of a rectifying circuit connected across the secondary winding so as to generate a predetermined DC output, a choke coil (L1) and a diode (D1) are interposed between the rectifying circuit (RC1) and a smoothing capacitor (C1) and a capacitor (C3) is interposed between a first junction and a second junction. The first junction connects the choke coil (L1) to the diode (D1) and the second junction connected the switching device (Q1) to the primary winding (n1) of the transformer (Tr1).

High power factor AC/DC converter

A wafer transfer method and mechanism in a vertical CVD diffusion apparatus and a control device for the method and mechanism. The vertical-type CVD diffusion apparatus has a boat containing many wafers in a horizontal orientation, stacked vertically. Product wafers are transferred to the boat five by five, dummy wafers are transferred five by five or a fraction less than five, and monitor wafers are inserted one by one between a block of the product wafers and another block of the product wafers, or a block of the dummy wafers.

Wafer transfer mechanism in vertical CVD diffusion apparatus

A wafer transfer method and mechanism in a vertical CVD diffusion apparatus and a control device for the method and mechanism. The vertical-type CVD diffusing apparatus has a boat containing many wafers in a horizontal orientation, stacked vertically. Product wafers are transferred to the boat five by five, dummy wafers are transferred five by five or a fraction less than five, and monitor wafers are inserted one by one between a block of the product wafers and another block of the product wafers, or a block of the dummy wafers.

Wafer transfer method in vertical CVD diffusion apparatus

A series resonant power converter in which a resonant copacitor is commonly used in a series resonant circuit and a parallel resonant circuit, whereby a capacitance of the resonant capacitor can be considerably decreased as compared with that of a tank circuit according to a prior art, so that an energy handled by the resonant capacitor can be decreased, which results in decreasing a size of the resonant circuit and also decreasing a power loss. The converter includes means for detecting and computing a voltage applied across a main switch means in its OFF-state and a control circuit for driving the main switch means to its ON-state when the detected and computed value of the voltage drops to a minimum voltage required to sustain oscillation of the series resonant circuit. The minimum voltage is computed by a detecting circuit for detecting an input voltage, a detecting circuit for detecting a voltage of a second resonant circuit and a detecting circuit for detecting a DC output voltage converted to a primary side of a main transformer.

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Tokyo, Japan

Ryoji Saito