Mitsubishi Denki Kabushiki Kaisha

Hiroshi Ohji

Kazuhiko Tsutsumi

Naoki Yutani

Patrick James French

Yuichi Sakai

Shinichi Izuo

An electrochemical etching system has an etching bath for holding an n-type silicon substrate with a first surface of the substrate in contact with hydrofluoric acid, an electrode positioned in the hydrofluoric acid, a power source having a positive pole connected to the silicon substrate and a negative pole connected to the electrode, and an illumination unit having a light source for illumination of a second surface of the silicon substrate. The illumination unit illuminates the second surface of the silicon substrate with an illumination intensity of 10 m W/cm or more. A ratio of a maximum illumination to a minimum illumination of the second surface of the silicon substrate is 1.69:1 or less. With the etching system, pores and/or trenches of a certain size and shape can be formed in an entire area of the silicon substrate having a diameter of more than three inches.

Method and apparatus for radiation assisted electrochemical etching and etched product

A pressure sensor includes a first diaphragm having a first surface receiving pressure, a first thermal detection section located opposite a central section of the first diaphragm, and a second thermal detection section having little displacement by pressure, and located opposite the first diaphragm The pressure sensor amplifies and outputs a difference between the first thermal detection section for pressure measurement and the second thermal detection section for reference output. Since the diaphragm to which the second thermal detection section is opposed is equal in thickness to the diaphragm to which the first thermal detection section is opposed, pressure can be accurately measured relative to a sudden change in atmospheric temperature.

Pressure sensor

A pressure sensor includes a diaphragm having a first surface receiving pressure, and a first thermal detection section opposed to a central section of the diaphragm through a spacer and having a thermo-sensitive resistance section, and a second thermal detection section opposed to an end section of the diaphragm and having a thermo-sensitive resistance section, wherein the first thermo-sensitive resistance section and second thermo-sensitive resistance section are connected to independent, adjustable constant-current sources, respectively, and are connected to a differential amplifier which amplifies a difference between (i) a voltage of the first thermal detection section, which detects a displacement quantity of the diaphragm due to pressure change as a displacement quantity of a thermal equilibrium state by the thermal detection section, and (ii) a voltage of the second thermal detection section, which does not change according to pressure. The sensor can measure pressure with high accuracy.

A pressure sensor of the present invention comprises a diaphragm having a first surface which receives pressure and a thermal detecting portion with a heat sensitive portion disposed as to oppose the diaphragm through a spacer, wherein displacement values of the diaphragm owing to variations in pressure are detected at the thermal detecting portion as variation values of thermal equilibrium state. With this arrangement, a surface of the diaphragm which directly receives pressure from measuring fluid does not need to undergo film forming or photolithographic processes whereby main portions of thermal pressure detecting elements might be formed onto a silicon substrate by large quantities in a lump sum through simple manufacturing processes so that it is possible to improve accuracy and reliability of the thermal pressure detecting elements and to obtain a pressure sensor of low cost.

Pressure sensor with a thermal pressure detecting element

A method of manufacturing a silicon device with a single crystal structure, including forming etching start patterns on a surface of a silicon substrate; etching the silicon substrate by applying a voltage to the silicon substrate while the silicon substrate is immersed in a solution containing fluorine ions, with the silicon substrate used a positive electrode, to form narrow etched portions that extend into the substrate from the etching start patterns; and accelerating etching of the silicon substrate by increasing current flowing through the silicon substrate after the narrow etched portions have reached a predetermined depth, so that neighboring etched portions are in communication with each other below the narrow etched portions and a free standing structure including part of the silicon substrate is formed, and a hollow portion is formed below the free standing structure.

Manufacturing method of silicon device

A multilayered soft magnetic film including a substrate, and a cyclic structure formed on the substrate and comprised of a main magnetic film composed of either Fe or an alloy containing the same as a main component thereof and a base film composed of either Ni-Fe alloy or an alloy containing the same as a main component thereof which are stacked alternately and repeatedly. The main magnetic film is 500 nm thick or thinner per film, while the base film is 20 nm thick or thinner per film. A thickness ratio of the main magnetic film to the base film per film is 1 or larger. The multilayered soft magnetic film exhibits good soft magnetic properties form the very beginning while maintaining a high initial permeability even after subjected to a heat treatment at a high temperature.

Growing community of inventors

Tokyo, Japan

Hiroshi Ohji