Rohm Co., Ltd.

Other

Canon Kabushiki Kaisha

Tadahiro Ohmi

Kazuhide Ino

Masashi Hayashiguchi

Masaki Hirayama

Yasuyuki Shirai

Takahiro Arakawa

Nobuyoshi Tanaka

Junichi Hikita

Takahisa Nitta

Hiroshi Osawa

Ikuo Yoshida

Toshikuni Shinohara

Mineo Miura

Ryu Kaiwara

Taiji Hashimoto

A switching deviceincludes a SiC semiconductor chipwhich has a gate pad, a source padand a drain padand in which on-off control is performed between the source and the drain by applying a drive voltage between the gate and the source in a state where a potential difference is applied between the source and the drain, a sense source terminalelectrically connected to the source padfor applying the drive voltage, and an external resistance (source wire) that is interposed in a current path between the sense source terminaland the source pad, is separated from sense source terminal, and has a predetermined size.

Switching device and electronic circuit

Provided is an electronic circuit capable of preventing a switching device from breakage when a short-circuit occurs. When a gate control signal CGis inverted from an L level to an H level, a first switching circuitselects a first input terminal a, and connects an output terminal d to the first input terminal a, whereby turning on a MOSFET. When a predetermined time Tx elapses after the output terminal d of the first switching circuitis connected to the first input terminal a, a second switching circuitselects a first input terminal e, and connects an output terminal g to the first input terminal e. Furthermore, immediately after the connection, the first switching circuitselects a second input terminal b, and connects the output terminal d to the second input terminal b. Consequently, immediately after the MOSFETis turned on, a gate resistor is switched from a first gate resistorhaving a small resistance value to a second gate resistorhaving a large resistance value.

Electronic circuit

When an overcurrent is detected by an overcurrent detecting circuit (), a first switch circuit () selects a second input terminal (b) and connects an output terminal (c) to the second input terminal (b), with the result that the output terminal (c) of the first switch circuit () is put into a high-impedance state. The second switch circuit () selects a second output terminal (f) and connects an input terminal (d) to the second output terminal (f), with the result that the input terminal (d) of the second switch circuit () is grounded. That is, the gate of a first MOSFET () is grounded via a current interrupting resistor (). The resistance value of the current interrupting resistor () is set so that, at the time of a current interruption, a time interval from a time when the gate-source voltage or gate-emitter voltage of the switching device lowers to such a voltage that the temperature characteristics of the on-resistance of the switching device become negative to a time when the drain current or collector current of the switching device reaches 2% of the saturation current thereof is 500 [nsec] or less.

A plasma processing apparatus for processing an object to be processed using a plasma. The apparatus includes a processing chamber defining a processing cavity for containing an object to be processed and a process gas therein, a microwave radiating antenna having a microwave radiating surface for radiating a microwave in order to excite a plasma in the processing cavity, and a dielectric body provided so as to be opposed to the microwave radiating surface, in which the distance D between the microwave radiating surface and a surface of the dielectric body facing away from the microwave radiating surface, which is represented with the wavelength of the microwave being a distance unit, is determined to be in the range satisfying the inequality0.7&#xd7;/4&#x2266;&#x2266;1.3&#xd7;/4 (being a natural number).

Plasma processing apparatus and plasma processing method

A plasma processing apparatus for processing an object to be processed using a plasma. The apparatus includes a processing chamber defining a processing cavity for containing an object to be processed and a process gas therein, a microwave radiating antenna having a microwave radiating surface for radiating a microwave in order to excite a plasma in the processing cavity, and a dielectric body provided so as to be opposed to the microwave radiating surface, in which the distance D between the microwave radiating surface and a surface of the dielectric body facing away from the microwave radiating surface, which is represented with the wavelength of the microwave being a distance unit, is determined to be in the range satisfying the inequality 0.7&#xd7;n/4&#x2266;D&#x2266;1.3&#xd7;n/4 (n being a natural number).

A method of producing a semiconductor device by dividing a semiconductor wafer into separate pieces of semiconductor chips. This method includes forming a groove with a pattern according to an outer contour of a desired semiconductor chip, holding the semiconductor wafer by a wafer holding mechanism, grinding a back surface of the semiconductor wafer held by the wafer holding mechanism, detecting opening of a bottom face of the groove during the back surface grinding process to determine timing for finishing the back surface grinding. The opening of the groove can be detected by means of a light sensor for detecting light passing through the groove or a microwave sensor for detecting a microwave passing through the groove. In addition, it is possible to suck air inside the groove so as to detect the opening of the groove by a pressure rise in the air inside the groove.

Method of producing a semiconductor device by dividing a semiconductor wafer into separate pieces of semiconductor chips

A gas supply path structure forms a fluid path for allowing a laser gas to flow into or out of a pair of fluid inlet and outletand a laser gas is controlled to a predetermined subsonic speed at a throat portion. Gas supplies for controlling the speed of the gas are connected each to the fluid inlet and to the fluid outlet of the gas supply path structure and, together with a cooling device, compose a circulation system for controlling the speed and pressure of the laser gas at the fluid inlet and/or at the fluid outlet.

Growing community of inventors

Kyoto, Japan

Kazuhide Ino