694 results about "Saturation current" patented technology

An amorphous oxide containing hydrogen (or deuterium) is applied to a channel layer of a transistor. Accordingly, a thin film transistor having superior TFT properties can be realized, the superior TFT properties including a small hysteresis, normally OFF operation, a high ON/OFF ratio, a high saturated current, and the like. Furthermore, as a method for manufacturing a channel layer made of an amorphous oxide, film formation is performed in an atmosphere containing a hydrogen gas and an oxygen gas, so that the carrier concentration of the amorphous oxide can be controlled.

A magnetic device includes a T-shaped magnetic core, a wire coil and a magnetic body. The T-shaped magnetic core includes a base and a pillar, and is made of an annealed soft magnetic metal material, a core loss P_CL (mW/cm³) of the T-shaped magnetic core satisfying: 0.64×f^0.95×B_m^2.20≦P_CL≦7.26×f^1.41×B_m^1.08, where f (kHz) represents a frequency of a magnetic field applied to the T-shaped magnetic core, and Bm (kGauss) represents the operating magnetic flux density of the magnetic field at the frequency. The magnetic body fully covers the pillar, any part of the base that is located above the bottom surface of the base, and any part of the wire coil that is located directly above the top surface of the base.

By using, as a model expression, an expression showing an inverse proportion between a change rate ΔIdsat/Idsat of saturated current value and a product of a gate protrusion length E1 and a gate width Wg of a transistor and a coefficient, modeling is executed for a transistor property that depends on the gate protrusion length. This provides a circuit simulation that takes into consideration the gate protrusion length of a gate electrode.

The invention discloses a micromechanical silicon-based clamped beam-based phase detector and a detection method. The phase detector comprises a silicon substrate (1), a source (2), a drain (3), a first clamped beam-anchoring area (61), a second clamped beam-anchoring area (62), a grid (5) and a clamped beam (7), wherein the source (2) and the drain (3) are grown on the surface of the silicon substrate (1) and used for outputting saturation current, the source (2) is arranged opposite from the drain (3), and the clamped beam (7) is arranged upon the grid (5) and is opposite to the grid (5). The detection method includes the following steps: when a direct-current offset is loaded on a first pull-down electrode (81) and a second pull-down electrode (82) and the clamped beam (7) is pulled down and is in contact with the grid (5), two microwave signals which have the same frequency and certain phase difference are simultaneously loaded on the grid (5); the saturation current of the drain (3) is processed, so that high-frequency signals are filtered, and therefore the current signal of phase difference information is obtained. The structure of the phase detector is simple, and measurement is easy.

An emitter layer is provided in stripes in a direction orthogonal to an effective gate trench region connected to a gate electrode and a dummy trench region isolated from the gate electrode. A width of the emitter layer is determined to satisfy a predetermined relational expression so as not to cause latch-up in an underlying P base layer. In the predetermined relational expression, an upper limit value of the width W of the emitter layer is (3500/Rspb)·Wso·exp(decimation ratio), where Rspb is a sheet resistance of the P base layer immediately below the emitter layer, Wso is an interval between the trenches, and the decimation ratio is a ratio of the number of the effective gate trench region to the total number of the trench regions. Variations in saturation current in a trench IGBT can be suppressed, and a tolerance of an Reverse Bias Safe Operation Area can be improved.

A UMOSFET is capable of reducing a threshold voltage and producing a large saturation current. A typical UMOSFET according to the present invention includes: an N⁺ type SiC substrate constituting a drain layer; an N⁻ type SiC layer that is in contact with the drain layer and constitutes a drift layer; a P type body layer formed on the drift layer and being a semiconductor layer; an N⁺ type SiC layer constituting a source layer; a trench extending from the source layer to a predetermined location placed in the drift layer; a P type electric field relaxation region provided around and outside a bottom portion of the trench; and a channel region extending from the N⁺ type source layer to the P type electric field relaxation region and having an impurity concentration higher than that of the N⁻ type drift layer and lower than that of the P type body layer.

A semiconductor device includes an IGBT, a constant voltage circuit, and protection Zener diodes. The IGBT makes/breaks a low-voltage current flowing in a primary coil. The constant voltage circuit and the protection Zener diodes are provided between an external gate terminal and an external collector terminal. The constant voltage circuit supplies a constant gate voltage to the IGBT to thereby set a saturation current value of the IGBT to a predetermined limiting current value. The IGBT has the saturation current value in a limiting current value range of the semiconductor device.

An object is to provide a semiconductor device having electrical characteristics such as high withstand voltage, low reverse saturation current, and high on-state current. In particular, an object is to provide a power diode and a rectifier which include non-linear elements. An embodiment of the present invention is a semiconductor device including a first electrode, a gate insulating layer covering the first electrode, an oxide semiconductor layer in contact with the gate insulating layer and overlapping with the first electrode, a pair of second electrodes covering end portions of the oxide semiconductor layer, an insulating layer covering the pair of second electrodes and the oxide semiconductor layer, and a third electrode in contact with the insulating layer and between the pair of second electrodes. The pair of second electrodes are in contact with end surfaces of the oxide semiconductor layer.

The invention discloses a micromechanical silicon-based clamped beam-based frequency detector and a detection method. The frequency detector comprises a power divider (P), a 90-degree phase shifter (Y), a low-pass filter (L) and a silicon-based metal-oxide-semiconductor field effect transistor; and the power divider is used for receiving a microwave signal to be detected and dividing the microwave signal to be detected into two branch signals with the same amplitude and phase. The detection method includes the following steps: when a direct-current offset is loaded on a first pull-down electrode (81) and a second pull-down electrode (82) and a clamped beam (7) is pulled down and is in contact with a grid (5), two channels of microwave signals are simultaneously loaded on the grid (5), the silicon-based metal-oxide-semiconductor field effect transistor is in a frequency detection state, the saturation current output between a source (2) and a drain (3) contains the current component of the frequency information of the signal to be detected, and by detecting the magnitude of saturation current, frequency detection is finally fulfilled. The structure of the frequency detector is simple, and measurement is easy.

The present invention is a method of and an apparatus for measuring resistances of at least one transformer winding (109) in configurations of connected transformers windings. The method is based on increasing driving power from the source of electrical energy (12, 102) until the current reaches a predetermined level, which is below the core saturation current level of the measured transformer or the measuring device current limit, and then controls the power of the source of the electrical energy to maintain predetermined current flowing through the at least one winding over a time period sufficient to cause a L di/dt contribution to a voltage drop across the at least one winding to decrease below a threshold level. The apparatus measures simultaneously the constant current flowing in the at least one winding and the voltage drop over the at least one winding after the predetermined time period has elapsed. The resistance of the at least one winding is calculated from the voltage drop over the at least one winding and the current flowing in the at least one winding.

Methods are provided for producing optical carrierographic images of a semiconductor sample. Focused and spatially overlapped optical beams excite carriers across within the semiconductor sample, where the optical beams are modulated such that a beat frequency is substantially less than either modulation frequency. An infrared detector detects infrared radiation emitted from the semiconductor sample in response to absorption of the optical beams, thereby obtaining a plurality of carrierographic signals at different points in time during at least one beat period, which are processed with a lock-in amplifier, with a reference signal at the beat frequency, to obtain an amplitude signal and a phase signal. Carrierographic lock-in images of the sample are obtained in a scanning configuration, or in an imaging format using an imaging detector. The images carry quantitative information about recombination lifetimes in substrate Si wafers and electrical parameters in solar cells, namely photogeneration current density, diode saturation current density, ideality factor, and maximum power photovoltage.

The invention discloses a charge storage-type insulated gate bipolar transistor with a trench gate and a manufacturing method of the charge storage-type insulated gate bipolar transistor and belongs to the field of semiconductor power devices. A trench emitter structure is introduced into an N-type drift region of a traditional CSTBT structure, a P-type layer and a series diode structure are sequentially introduced to the lower part and the surface of the trench emitter structure, and meanwhile, the insulated gate bipolar transistor has a trench gate structure which partially penetrates into an N-type charge storage layer along the vertical direction, so that the problem of a contradictory relationship between the positive conduction performance and the voltage resistance of a device due to improvement of the doping concentration of the N-type charge storage layer in the traditional CSTBT is solved through the improvement; the saturation current density of the device is reduced and a short-circuit safety operation area of the device is improved; the switching speed of the device is improved and the switching loss is reduced; the breakdown voltage of the device is improved and the reliability is improved; compromise between a positive conduction voltage drop and the turn-off loss is optimized; and meanwhile, the manufacturing method of the device is compatible with a manufacturing technology of an existing CSTBT device.

The invention provides an electro-thermal simulation method for FS (Field Stop) type IGBT (Insulated Gate Bipolar Transistor) transient temperature characteristic. An FS type IGBT switching transient working process is actually tested and is analyzed by being combined with an IGBT working principle and a semiconductor physical principle to determine that the IGBT transient temperature characteristic is mainly influenced by life of internal excess carrier, so that the electro-thermal simulation method is established. The method comprises the following steps of: actually testing carrier life values extracted at different temperatures to acquire a relational expression of the carrier life and temperature; calculating through an empirical value formula to acquire a relational expression amongthreshold voltage, transconductance, emitter saturation and current as well as the temperature; and adding temperature related parameters into an FS type IGBT current tailing stage current analyticalexpression and a switching transient model equation set and calculating to acquire transient working waveform of the FS type IGBT at different temperatures. The electro-thermal model simulation method provided by the invention simultaneously has the advantages of simple parameter calculation and high accuracy.

The invention discloses a photoelectric detector based on graphene/boron-doped silicon quantum dots/silicon and a preparation method thereof. The photoelectric detector comprises an n type silicon substrate, a top electrode, a graphene film, a boron-doped silicon quantum dot film, and a bottom electrode. The photoelectric detector can carry out wide spectral detection, and a problem of low infrared detection response of a traditional silicon-based PIN junction is solved. According to the detector, graphene is used as an active layer and a transparent electrode, a dead layer is eliminated, and the absorption of incident light is enhanced. The boron-doped silicon quantum dot film is in the middle, the influence of a silicon surface state is reduced, and the reverse saturation current is suppressed at the same time. Under a certain reverse bias voltage effect, collision ionization is generated by photon-generated carriers and silicon lattice, and a high photoelectric response is obtained. The photoelectric detector and the preparation method have the advantages of a simple preparation process, low cost, a high response degree, fast response speed, a large internal gain, a small switching ratio, and easy integration.

A non-linear element (e.g., a diode) with small reverse saturation current is provided. A non-linear element includes a first electrode provided over a substrate, an oxide semiconductor film provided on and in contact with the first electrode, a second electrode provided on and in contact with the oxide semiconductor film, a gate insulating film covering the first electrode, the oxide semiconductor film, and the second electrode, and a third electrode provided in contact with the gate insulating film and adjacent to a side surface of the oxide semiconductor film with the gate insulating film interposed therebetween or a third electrode provided in contact with the gate insulating film and surrounding the second electrode. The third electrode is connected to the first electrode or the second electrode.

Provided are high voltage metal oxide semiconductor field effect transistor (HVMOSFET) having a Si/SiGe heterojunction structure and method of manufacturing the same. In this method, a substrate on which a Si layer, a relaxed SiGe epitaxial layer, a SiGe epitaxial layer, and a Si epitaxial layer are stacked or a substrate on which a Si layer having a well region, a SiGe epitaxial layer, and a Si epitaxial layer are stacked is formed. For the device having the heterojunction structure, the number of conduction carriers through a potential well and the mobility of the carriers increase to reduce an on resistance, thus increasing saturation current. Also, an intensity of vertical electric field decreases so that a breakdown voltage can be maintained at a very high level. Further, a reduction in vertical electric field due to the heterojunction structure leads to a gain in transconductance (Gm), with the results that a hot electron effect is inhibited and the reliability of the device is enhanced.

The invention discloses a cantilever beam frequency detector and a cantilever beam frequency detection method based on micromechanical gallium arsenide. The frequency detector comprises a power divider (PD), a phase shifter (PS), a low pass filter (F) and a gallium arsenide metal semiconductor field effect transistor (MESFET), wherein the PD is used for receiving a microwave signal to be detected and dividing the microwave signal to be detected into two branch signals with the same amplitude and phase. The detection method comprises the following steps that: when a pull-down electrode (8) is loaded with direct current (DC) offset and a cantilever beam (6) is pulled down and contacted with a gate (4), the gate (4) is loaded with the two paths of microwave signals simultaneously, so that the magnitude of saturation current between a source (2) and a drain (3) is changed; and through a capacitor and a filter, the frequency is measured by detecting the magnitude of the saturation current between the source (2) and the drain (3). By the detector and the method, DC power consumption is low, and the frequency is easy to measure.

A field emitter array structure is provided. The field emitter array structure includes a plurality of vertical un-gated transistor structures formed on a semiconductor substrate. The semiconductor substrate includes a plurality of vertical pillar structures to define said un-gated transistor structures. A plurality of emitter structures are formed on said vertical un-gated transistor structures. Each of said emitter structures is positioned in a ballasting fashion on one of said vertical un-gated transistor structures so as to allow said vertical ungated transistor structure to effectively provide high dynamic resistance with large saturation currents.

An RFI/EMI filter for a variable frequency motor drive system includes a variable frequency drive; a common mode choke; a motor; a cable including a plurality of power leads interconnecting the motor with the variable frequency drive and passing through the choke; a ground shield surrounding the cable and connected to motor ground and variable frequency drive ground; and a common mode return conductor interconnected between the variable frequency drive and the motor and disposed within the shield and passing through the choke for returning a portion of the common mode current to cancel a portion of the saturation current experienced by the choke to increase the portion of the common mode current carried by the return conductor and decrease the portion carried by the shield to reduce the RFI/EMI contributed by the shield.

With a non-linear element (e.g., a diode) with small reverse saturation current, a power diode or rectifier is provided. A non-linear element includes a first electrode provided over a substrate, an oxide semiconductor film provided on and in contact with the first electrode and having a concentration of hydrogen of 5×10¹⁹ atoms/cm³ or less, a second electrode provided on and in contact with the oxide semiconductor film, a gate insulating film covering the first electrode, the oxide semiconductor film, and the second electrode, and third electrodes provided in contact with the gate insulating film and facing each other with the first electrode, the oxide semiconductor film, and the second electrode interposed therebetween or a third electrode provided in contact with the gate insulating film and surrounding the second electrode. The third electrodes are connected to the first electrode or the second electrode. With the non-linear element, a power diode or a rectifier is formed.

Various embodiments of the invention use the characteristics of BJTs to compute parameter values required to de-embed the effects of non-idealities including BJT's-mismatch in the reverse saturation current and process-dependent injection factor. In some embodiments, a temperature sensor circuit and method provide high temperature accuracy in a low-cost way by individually calibrating each part, thereby, eliminating the need to accurately measure temperature with a precision temperature sensor.