Abstract: 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.

Abstract: An inertia force sensor having a mass body (11) which moves when force is applied to the sensor, at least one holding beam (12) for holding the mass body (11), and an anchor portion (13) for fixing an end portion of the holding beam (12), the sensor being designed to detect inertia force, which acts on the mass body (11), on the basis of a movement of the mass body (11). The sensor is characterized in that the mass body (11) is composed of a free standing structure (9) which is formed by removing an inner part of a silicon substrate (1) therefrom by means of an etching process within a single step, and the anchor portion (13) is composed of at least a part of a main body of the silicon substrate. Because the inertia force sensor is composed of single crystal silicon, its mechanical properties and reliability may be highly improved.

Abstract: A piezoresistive device, in which separation grooves having a cross section defined by four (111) planes and including side walls of a silicon oxide film are formed in a surface area of a semiconductor substrate having a surface of (100) plane, and at least one piezoresistor having an inversed triangular cross section defined by one (100) plane and two (111) planes is formed in the surface area of the semiconductor substrate and is surrounded by the separation grooves for separating the piezoresistor from the semiconductor substrate.

Abstract: The photo-sensor cell comprises two optical flip-flop sensors having two different light intensity thresholds, respectively , under imbalanced load offset conditions, two logic cells for latching only two different binary level signals from the two optical sensor respectively, without latching two of the same binary level signals from the two optical sensors due to a high or low pulsed power supply, and an output logic cell for generating an output binary signal from the time when light intensity rises beyond a higher threshold to the time when it drops below a lower threshold. Since all the elements are standardized in an IC manufacturing process and further no synchronizing clock signals are required between cells and signal processing logic owing to latch operations when a number of cells are connected in series or parallel, it is possible to realize a compact digital photo-sensor cell assembly with hysteresis activated by a pulsed power supply.