Abstract:
MOS-gated power device comprising a plurality of elementary functional units, each elementary functional unit comprising a body region (3) of a first conductivity type formed in a semiconductor material layer (2; 21,22,23) of a second conductivity type. A plurality of doped regions (20; 201,202) of a first conductivity type is formed in the semiconductor material layer (2; 21,22,23), each one of the doped regions being disposed under a respective body region (3) and being separated from other doped regions by portions of the semiconductor material layer (2; 21,22,23).
Abstract:
PROBLEM TO BE SOLVED: To provide an acoustic sensor in which shock resistance is improved.SOLUTION: An acoustic sensor 11 comprises a vibration film 22 and a fixed film 23 formed on the upper surface of a semiconductor substrate and detects a sonic wave by changes in a capacitance between a vibration electrode 22a of the vibration film 22 and a fixed electrode 23a of the fixed film 23. The fixed film 23 has a plurality of sound hole parts 32 bored to allow the sonic wave to reach the vibration film 22 from outside, and the fixed electrode 23a is formed so that the boundary of an edge 40 does not cross the sound hole parts 32.
Abstract:
PROBLEM TO BE SOLVED: To provide a micro-electro-mechanical gyroscope, along with a method for controlling the micro-electro-mechanical gyroscope, suitable for a wide-range development which is precise and whose reliability is high. SOLUTION: The MEMS gyroscope includes: a minute structure 2 having a fixed structure 6, a movable drive mass body 7 concerning the fixed structure 6 in accordance to a drive axis X, and a movable detection mass body 8 mechanically connected to the drive mass body 7 so as to be a motion state in accordance to the drive axis X and concerning the drive mass body 7 in accordance with a drive axis Y in response to rotation of the minute structure 2; and a drive device 3 for maintaining the drive mass body 7 at a drive frequency in a vibration state. The drive device 3 includes: a discrete time detection interface 20 for detecting the position of the drive mass body 7 concerning the drive axis X; and control means 21, 23, 24, 25 for controlling a drive frequency on the basis of the position of the drive mass body 7. COPYRIGHT: (C)2011,JPO&INPIT
Abstract:
Method of manufacturing an edge structure for a high voltage semiconductor device, comprising a first step of forming a first semiconductor layer (41) of a first conductivity type, a second step of forming a first mask (37) over the top surface of the first semiconductor layer (41), a third step of removing portions of the first mask (37) in order to form at least one opening (51) in it, a fourth step of introducing dopant of a second conductivity type in the first semiconductor layer (41) through the at least one opening (51), a fifth step of completely removing the first mask (37) and of forming a second semiconductor layer (42) of the first conductivity type over the first semiconductor layer (41), a sixth step of diffusing the dopant implanted in the first semiconductor layer (41) in order to form a doped region (220) of the second conductivity type in the first and second semiconductor layers (41, 42). The second step up to the sixth step are repeated at least one time in order to form a final edge structure comprising a number of superimposed semiconductor layers (41, 42, 43, 44, 45, 46) of the first conductivity type and at least two columns of doped regions (220, 230, 240, 250, 260) of the second conductivity type, the columns being inserted in the number of superimposed semiconductor layers (41, 42, 43, 44, 45, 46) and formed by means of superimposition of the doped regions (220, 230, 240, 250, 260) subsequently implanted through the mask openings, the column near the high voltage semiconductor device being deeper than the column farther to the high voltage semiconductor device.
Abstract:
PROBLEM TO BE SOLVED: To suppress a phase current generated in winding of a stator over a full speed range of motor when driving a stepper motor in a voltage mode. SOLUTION: A method of driving a stepper motor in feed-forward voltage mode includes (A) a step of setting the amplitude of a sinusoidal phase voltage of the stepper motor to a predetermined value to rotate the stepper motor at a desired speed. The predetermined value is the sum of a back-electromotive force (BEMF) estimated via a function of the desired speed and a product of a desired amplitude of a phase current (Iphase) and an estimated absolute value of the impedance of the stepper motor. COPYRIGHT: (C)2011,JPO&INPIT