Abstract: A very small and economical acceleration sensor which can detect acting acceleration with high sensitivity and high accuracy by precisely processing a semiconductor substrate and the like by using the photoengraving technique in a semiconductor manufacturing process to accurately form the elements themselves such as a sensor case, a cavity, a heater, a temperature-sensing resistor element, and a heat-type temperature-sensing resistor element, and the relative placement of each element. One embodiment of the acceleration sensor can detect acceleration acting from any of the three-dimensional directions.

Abstract: A hybrid sensor which is comprised of an acceleration sensor for detecting acceleration based on a temperature distribution of a predetermined gas hermetically enclosed within a fluid-tight space, and an angular velocity sensor for detecting angular velocity based on a deviation of a flow of a predetermined gas. The acceleration sensor and the angular velocity sensor are formed in one piece by the use of semiconductor processing technology in such a manner that the acceleration sensor and the angular velocity sensor are formed on a plurality of semiconductor substrates, and then the plurality of semiconductor substrates are superposed one upon another and united into a laminate.

Abstract: A very small and economical acceleration sensor which can detect acting acceleration with high sensitivity and high accuracy by precisely processing a semiconductor substrate and the like by using the photoengraving technique in a semiconductor manufacturing process to accurately form the elements themselves such as a sensor case, a cavity, a heater, a temperature-sensing resistor element, and a heat-type temperature-sensing resistor element, and the relative placement of each element. One embodiment of the acceleration sensor can detect acceleration acting from any of the three-dimensional directions.

Abstract: A gas flow type sensor with heat-wire bridge having an excellent performance which is attained by optimizing a sputtering process and a heat treatment process for forming a three-layer film (SiN-Pt-SiN) on a semiconductor substrate and improving interfacial adhesion of the three layers and, at the same time, effectively reducing any interfacial stress produced therein. The process comprises a film forming process for sequentially depositing by sputtering SiN, Pt and SiN in three layers on a semiconductor substrate and a heat treatment process for heat treatment of the coated films at a temperature up to 600.degree. C.

Abstract: A semiconductor type gas rate sensor which is capable of accurately sensing with a sufficient sensitivity an angular velocity acting on its body made of semiconductor substrates having a nozzle port and a gas path etched therein with a pair of heat wires (heat-sensitive resistance elements) provided in the gas path, wherein an optimal flow of gas injected into the gas path through the nozzle port is ensured by designing the nozzle port of 300 to 1000 microns in width and of not less than 2 mm in length and providing the gas path at its downstream end with an outlet allowing the gas to flow straight out from the gas path therethrough.

Abstract: A gas flow type angular velocity sensor which is capable of reliably sensing an angular velocity while accurately controlling the working gas flow with temperature compensation by using a pair of heat wires as a gas flow sensor without providing any additional gas flow sensor in the sensor body wherein an angular velocity sensing bridge circuit is provided at its current supply source with a temperature compensating circuit connected in series which temperature compensating circuit is composed of a pair of series or parallel connected resistance elements, one of which is a thermosensitive resistance element disposed in a gas path and the other of which is a reference resistance element disposed outside the gas path.

Abstract: A gas flow type angular velocity sensor comprising two semiconductor substrates wherein only the first semiconductor substrate is provided with a groove etched thereon constituting the gas path and the second semiconductor substrate is provided with paired heat wires formed thereon. The two semiconductor substrates are coupled and bonded to each other to form the sensor body.

Abstract: This invention relates to a semiconductor sensor for detecting external physical forces, such as acceleration, contact pressures, air pressures, mechanical vibrations, etc. The semiconductor sensor according to this invention is characterized by the use of compound semiconductors of high piezoelectricity, such as GaAs, etc. Conventionally sensors of the cantilever type, diaphragm type, etc. are made of silicon. These prior art sensors have low detection sensitivity, and their characteristics tend to deteriorate. The sensor according to this invention is made of GaAs, which has high piezoelectricity and can retain good characteristics of the semiconductor even at high temperatures and includes a field-effect transistor formed on the GaAs for sensing a stress. The FET is driven by a constant current or a constant voltage so as to detect a change of an electrical characteristic (e.g., threshold characteristic) due to a stress.

Abstract: This invention relates to a semiconductor sensor for detecting external physical forces, such as acceleration, contact pressures, air pressures, mechanical vibrations, etc. The semiconductor sensor according to this invention is characterized by the use of compound semiconductors of high piezoelectricity, such as GaAs, etc. Conventionally sensors of the cantilever type, diaphragm type, etc. are made of silicon. These prior art sensors have low detection sensitivity, and their characteristics tend to deteriorate. The sensor according to this invention is made of GaAs, which has high piezoelectricity and can retain good characteristics of the semiconductor even at high temperatures and includes a field-effect transistor formed on the GaAs for sensing a stress. The FET is driven by a constant current or a constant voltage so as to detect a change of an electrical characteristic (e.g., threshold characteristic) due to a stress.