Hitachi, Ltd.

Fujitsu Corporation

Renesas Technology Corp.

Hiroshi Ohta

Hitoshi Nishimura

Masakazu Aoki

Hiroyuki Uchiyama

Hidetoshi Matsumoto

Tomonori Tanoue

Hiroyuki Matsuda

Kazuhiro Mochizuki

Takayoshi Iitsuka

Sumio Kikuchi

Kenichi Tanaka

Sachie Tone

Masahiro Ninomiya

Takashi Hirooka

The semiconductor substrate comprises a first monitor partformed in a first region near a center of a semiconductor wafer, which includes a first element having a first electrodeformed over the semiconductor waferwith a first insulation filmformed therebetween, and a first electrode padelectrically connected to the first electrode; and a second monitor partformed in a second region different from the first region, which includes a second element having a second electrodeformed on the semiconductor waferwith a second insulation filmformed therebetween, and a second electrode padelectrically connected to the second electrode. When electric breakdown has taken place in both the first monitor partand the second monitor part, it can be judged that too large static electricity was generated upon the release of the surface protection film. When electric breakdown has taken place in either of the first monitor partand the second monitor part, the electric breakdown has taken place due to factors other than the static electricity generated upon the release of the surface protection film. When electric breakdown has taken place in neither of the first monitor partand the second monitor part, it can be judged that too large static electricity was generated upon the release of the surface protection film. Thus, factors for defects of semiconductor devices can be identified, which leads to improved quality of the semiconductor devices.

Semiconductor substrate and semiconductor device fabrication method

This invention is intended to provide an HBT capable of achieving, if the HBT is a collector-up HBT, the constriction of the emitter layer disposed directly under an external base layer, and reduction in base-emitter junction capacity, or if the HBT is an emitter-up HBT, reduction in base-collector junction capacity. For the collector-up HBT, window structures around the sidewalls of a collector are used to etch either the emitter layer disposed directly under the external base layer, or an emitter contact layer For the emitter-up HBT, window structures around the sidewalls of an emitter are used to etch either the collector layer disposed directly under the external base layer, or a collector contact layer. In both HBTs, the external base layer is supported by a columnar structure to ensure mechanical strength.

Semiconductor device and method of manufacturing the same

An oil free screw compressor having a low-pressure stage compressor body and a high-pressure stage compressor body. Power of a motor driven by an inverter is transmitted to the compressor bodies through gears. A low-pressure stage blow-off two-way valve is provided in a pipe branching off midway an air pipe connecting between the high-pressure stage compressor body and the low-pressure stage compressor body, and a high-pressure stage blow-off two-way valve is provided in a pipe branching off from a discharge air pipe provided on a discharge side of the high-pressure stage compressor body. During no-load operation, a controller gives a command to the inverter to make the rotational speed of the motor a set lower limit rotational speed, and also gives an open command to the low-pressure stage blow-off two-way valve.

Oil free screw compressor operating at variable speeds and control method therefor

When converting a sequential execution source program into a parallel program to be executed by respective processors (nodes) of a distributed shared memory parallel computer, a compiler computer transforms the source program to increase a processing speed of the parallel program. First, a kernel loop having a longest sequential execution time is detected in the source program. Next, a data access pattern equal to that of the kernel loop is reproduced to generate a control code to control first touch data distribution. The first touch control code generated is inserted in the parallel program.

Parallel program generating method

An oil free screw compressor includes a low-pressure stage compressor body and a high-pressure stage compressor body. Power of a motor driven by an inverter is transmitted to the compressor bodies through gears. A low-pressure stage blow-off two-way valve is provided in a pipe branching off midway an air pipe connecting between the high-pressure stage compressor body and the low-pressure stage compressor body, and a high-pressure stage blow-off two-way valve is provided in a pipe branching off from a discharge air pipe provided on a discharge side of the high-pressure stage compressor body. During no-load operation, a controller gives a command to the inverter to make the rotational speed of the motor a set lower limit rotational speed, and also gives an open command to the low-pressure stage blow-off two-way valve.

In a capacity control method for an oil-free screw compressor, when an air consumption is larger than a set amount, a rotation frequency of a motor using an inverter to drive the compressor is set to be variable. When the air consumption is a set air amount or less, the inverter is controlled in such a manner that the rotation frequency of the motor is kept at a constant value. In this state, when an operation gas pressure of the compressor reaches an upper-limit value, an air release valve is opened to discharge the operation gas to the atmosphere. Additionally, the rotation frequency of the motor is lowered to a lower-limit value. Re-compression in the compressor can be prevented, and a compressor drive torque is lowered.

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Kawasaki, Japan

Hiroshi Ohta