12 results about "Conductivity modulation" patented technology

This invention provides a bidirectional transient voltage suppressor with low dynamic resistance and high surge capability, comprising: a heavily doped semiconductor substrate of a first conductivity type; a first epitaxial layer disposed on the substrate; a conduction modulation buried layer disposed on the first epitaxial layer; a second epitaxial layer disposed on the conduction modulation buried layer; a heavily doped first conductivity type region disposed on the second epitaxial layer; a first electrode disposed on the front side of the heavily doped first conductivity type region and a second electrode disposed on the back side of the substrate; the conduction modulation buried layer is disposed inside the double epitaxial body region and is configured to form a high-concentration conductivity modulation region of charge carriers under transient high current impact conditions, forming a body region-dominated conduction path between the first epitaxial layer and the second epitaxial layer, so that the conduction current changes from concentrated conduction in the PN junction region to a laterally extended and planar distributed overall conduction mode within the body region, thereby reducing the dynamic resistance of the device and improving the surge carrying capacity of the device.

This invention belongs to the field of semiconductor technology, specifically providing a gallium oxide insulated-gate bipolar transistor (IGBT) power device, including a vertical device and a horizontal device. This invention uses nickel oxide, copper oxide, or diamond as the P-type region, forming a heterojunction structure with N-type gallium oxide. During device operation, the heterojunction on the high-potential side is forward-biased, allowing a large number of holes to be injected into the N-type gallium oxide drift region. This introduces a conductivity modulation effect in the drift region, achieving high current density and low on-state voltage drop, thus realizing the basic working principle of the IGBT device. Simultaneously, the horizontal IGBT introduces P-type nickel oxide or diamond with N-type gallium oxide to form a superjunction structure with a high-voltage drift region, achieving higher breakdown voltage with the same drift region length, thus improving device performance. In summary, this invention, based on the principle of heterojunction, proposes the concept of gallium oxide IGBT for the first time, providing a new approach for the research of gallium oxide high-voltage, high-current power devices.

The invention belongs to the technical field of semiconductors, and relates to a GaN HEMT device with an adjustable threshold voltage structure. A PNP triode structure is introduced into a grid electrode of the device, an N-end extraction electrode serves as a threshold value control electrode, and a P-end extraction electrode on the topmost layer serves as the grid electrode. The gate voltage of the whole device must exceed the threshold value control electrode voltage and the opening voltage of the top PN junction, so that the channel of the device can be opened. Meanwhile, due to hole injection brought by the BJT structure, the structure of the invention also has a conductivity modulation effect, the transconductance of the device can be improved, and the grid control capability can be enhanced. The device is provided with the externally given threshold control electrode, so that the device can realize adjustable threshold voltage, and different threshold voltages can be realized by applying different voltages through the threshold control electrode.

A control system to control a conductivity modulation device of a power switch array. The control system includes: a system controller to receive an indication indicating that the system controller is to adjust a driving characteristic of the conductivity modulation device, and to output a command signal; and a switch controller configured to receive the command signal and control energy delivery to the load by controlling on and off of the conductivity modulation device. The switch controller comprises an adjustable driving element, an interface and a driving characteristic control device; the adjustable driving element is used for controlling rising time and / or falling time of voltage on the conductivity modulation device; an interface coupled to the system controller and configured to receive and interpret the command signal and output a drive characteristic signal, the driving characteristic control device is used for receiving a driving characteristic signal and changing the driving characteristic by controlling the adjustable driving element in response to the driving characteristic signal so as to adjust the rising time and / or the falling time of the voltage on the conductivity modulation device.

The invention provides a novel RC-IGBT structure with a hole circulation path and a good compromise relationship, which comprises a device main body, collector metal is arranged at the bottom of the device main body, a p + collector region, an FS layer, an n-drift region, a groove with a grid electrode at the top, an n + emitter region, a p + contact region and a p base region are sequentially arranged upwards, a second CS storage layer is arranged at the bottom, and the emitter composite structure on the two sides comprises a deep p-type region, a deeper p-type region, a hole channel and a CS storage layer. Through the above structure, the deep p-type region and the deeper p-type region optimize the electric field distribution, improve the doping concentration of the CS layer, enhance the hole accumulation effect, reduce the conduction voltage drop, accelerate the carrier export during the turn-off of a hole channel, and shorten the turn-off time, and at the same time, under the short-circuit working condition, the structures cooperatively export holes, weaken the conductivity modulation effect, improve the short-circuit endurance capability, and improve the performance of the device. And finally, good balance of voltage resistance, conduction voltage drop and switching speed is realized, and the comprehensive performance of the device is remarkably improved.

This invention discloses a Schottky diode and its fabrication method. The Schottky diode includes an N-type epitaxial layer and a barrier metal layer stacked sequentially from bottom to top. A trench extending in the front-back direction is formed on the upper side of the N-type epitaxial layer. The trench is filled with a channel structure, which includes a gate oxide layer, two polysilicon layers located on both sides of the gate oxide layer, and two lightly doped P-type layers located on both sides of the two polysilicon layers. A heavily doped P-type layer connected to the lightly doped P-type layer is provided on the upper side of the N-type epitaxial layer, and the heavily doped P-type layer is in contact with the barrier metal layer. The Schottky diode provided by this invention utilizes the ohmic contact formed by the heavily doped P-type layer and the barrier metal layer, and the lightly doped P-type layer as a conductivity modulation layer, which greatly improves the surge resistance of the device without affecting the switching characteristics of the Schottky diode.

The invention discloses a conductivity regulation and control method for semiconductor heterojunctions with different crystal orientations, and the method comprises the steps: obtaining the electrical energy band structures of two materials with different crystal orientations through employing a first principle calculation method, and calculating the effective mass of semiconductor materials with different crystal orientations; adopting a first principle calculation method to obtain conduction band orders of the two materials in different crystal orientations; solving the channel carrier concentration in the heterojunction composed of the two materials under different crystal orientations by combining a Schrodinger-Poisson equation; constructing a scattering mechanism of channel carriers in the heterojunction formed by the two materials under the different crystal orientations, and calculating the mobility of the channel carriers in the heterojunction formed by the two materials under the different crystal orientations; and according to the calculation model of the channel carrier concentration and mobility, obtaining the regulation and control method of the channel carrier conductance in the heterojunction composed of the two materials under different crystal orientations. According to the method, the relation between the physical parameters and the crystal orientation of the semiconductor heterojunction is extracted, efficient regulation and control of multi-system heterojunction conductivity are achieved, the model calculation amount is small, and universality is high.

The invention provides a charge throttling layer structure and method for reducing on resistance of a high-power high-voltage device. The charge throttling layer structure comprises a substrate, a charge throttling layer, an N + region and an oxide layer, the charge throttling layer, the N + region and the oxide layer are sequentially grown on the substrate from bottom to top; the charge throttling layer and the N + region are both doped regions, and the doping concentration of the N + region is larger than that of the charge throttling layer. In the manufacturing process of the high-voltage bipolar semiconductor power device, a multi-time and multi-step doping process (such as doping boron, phosphorus and aluminum impurities) is adopted, a charge throttling layer with specific concentration distribution is manufactured in a base region of the device, and the on-resistance of the base region of the device can be effectively reduced by enhancing the conductivity modulation effect in the conduction process of the device by the charge throttling layer, so that the on-resistance of the base region of the device is improved. And the heat accumulation of the device in the working process is reduced.

The invention provides a bidirectional transient voltage suppressor with low dynamic resistance and high surge capacity. The bidirectional transient voltage suppressor comprises a heavily doped first conductive type semiconductor substrate; the first epitaxial layer is arranged on the substrate; the conduction modulation buried layer is arranged on the first epitaxial layer; the second epitaxial layer is arranged on the conduction modulation buried layer; the heavily doped first conductive type region is arranged on the second epitaxial layer; the first electrode is arranged on the front surface of the heavily doped first conductive type region; the second electrode is arranged on the back surface of the substrate; the conduction modulation buried layer is arranged in the double epitaxial body region and is configured to form a carrier high-concentration conductivity modulation region under a transient large current impact condition, and a body region leading conduction path is formed between the first epitaxial layer and the second epitaxial layer; conduction current is converted from PN junction local area concentrated conduction into an integral conduction mode of transverse expansion and planar distribution in a body area range, so that the dynamic resistance of the device is reduced, and the surge bearing capacity of the device is improved.

This invention belongs to the field of power semiconductor technology, specifically relating to a trench gate-controlled composite power device with low on-state voltage and low switching losses. The device is a non-fully symmetrical composite structure, integrating an IGBT unit structure and a trench MOS gate-controlled thyristor (MCT) unit structure on the same semiconductor substrate. The device includes an anode structure, an electric field cutoff layer, an N-type drift region, a base region structure, a cathode structure, and a trench gate structure. The trench gate penetrates the base region and extends into the drift region, enabling the modulation of carriers in different regions. During conduction, the MCT structure triggers a PNPN conduction mechanism, enhancing the conductivity modulation effect and reducing the on-state voltage. During turn-off, the trench gate forms a carrier extraction channel within the N-type base region, accelerating minority carrier removal and thus reducing switching losses. This structure achieves synergistic optimization of conduction and switching performance by controlling the spatiotemporal distribution of carrier injection and extraction, making it suitable for high power density and high-frequency power electronics applications.

This invention discloses a quantum dot-modified flexible visual synaptic memristor and its fabrication method. The quantum dot-modified flexible visual synaptic memristor includes: a flexible substrate; a bottom electrode formed on the flexible substrate; a composite functional film composed of perovskite quantum dots and an organic ferroelectric polymer, formed on the bottom electrode; and multiple mutually spaced transparent top electrodes formed on the composite functional film. By applying light source signals and electrical pulse signals to the device, and utilizing the photoelectric response of the perovskite quantum dots and the conductivity modulation function of the ferroelectric polymer, the device simulates the light signal perception, data storage, and computation of an artificial vision system.

The invention discloses a reconfigurable memristor based on a two-dimensional covalent organic framework and a preparation method and application thereof.The memristor comprises a bottom electrode, a covalent organic framework-based active film layer and a top electrode which are sequentially arranged in a stacked mode, and the covalent organic framework-based active film layer is prepared by condensing 1, 3, 5-tri (4-aminophenyl) benzene and [1, 1 ': 4', 1 ''-terphenyl]-4, 4 ''-dicarboxaldehyde. According to the memristor, the covalent organic framework-based active film layer made of a specific material is adopted, so that reconfigurable switching between a synaptic mode and a pain neuron mode in the same device under different electrical regulation and control conditions is realized, and stable analog conductivity modulation and multi-level storage can be realized in the synaptic mode; threshold triggering and quick response can be achieved in a pain neuron mode, and a high-integration-level and low-power-consumption device implementation scheme is provided for an end-side neuromorphic hardware system.