Abstract: The present disclosure provides a power converter, comprising: a positive terminal, a neutral terminal, a negative terminal, a first intermediate node, a second intermediate node, and an AC terminal. Vertical and horizontal switches are configured to switch a DC voltage between the positive and negative terminal to an AC voltage at the AC terminal. The AC voltage comprises three main voltage levels. A transition between any two of the main voltage levels follow a trapezoidal shape with at least one voltage sub-level.

Abstract: The present disclosure relates to a quasi-multi-level power converter and a method of operating the same. The power converter is capable of reconciling scalable operation voltage, multiple output voltage levels, controllable voltage rising or decreasing slew rate, and a balance between the high voltage levels and the volume/weight of passive circuit components.

Abstract: A gate voltage magnitude compensation equalization method and circuit for series operation of power switch transistors are provided. A dynamic voltage equalization of series-connected power switch transistors is implemented by using sampling principles where voltages of the power switch transistors are controlled by gate voltage magnitude and unbalanced voltage differentials are converted into unbalanced current differentials of buffer currents. The gate voltage magnitude compensation equalization method and circuit relates to differential control and works in a dynamic voltage change process of the series-connected power switch transistors, without having a negative effect on operation of the power switch transistors under normal operating conditions.

Abstract: A gate voltage magnitude compensation equalization method and circuit for series operation of power switch transistors are provided. A dynamic voltage equalization of series-connected power switch transistors is implemented by using sampling principles where voltages of the power switch transistors are controlled by gate voltage magnitude and unbalanced voltage differentials are converted into unbalanced current differentials of buffer currents. The gate voltage magnitude compensation equalization method and circuit relates to differential control and works in a dynamic voltage change process of the series-connected power switch transistors, without having a negative effect on operation of the power switch transistors under normal operating conditions.

Abstract: A self-calibration apparatus and method for a real-time temperature measurement system of a MOCVD device belong to the technical field of semiconductor manufacturing. The apparatus comprises a MOCVD reactor chamber (1) and an optical detector (6). The MOCVD reactor chamber (1) comprises an epitaxial wafer (4). A detection window (5) is provided on the top of the MOCVD reactor chamber (1). The optical detector (6) emits detection light beams whose wavelengths are respectively ?1 and ?2 toward the epitaxial wafer (4) through the detection window (5). The detection light beams are reflected by the epitaxial wafer (4) to form reflected light beams which are detected by the optical detector (6). In the method, points corresponding to the actual thermal radiation ratios are depicted on the theoretical thermal radiation ratio-temperature curve according to actual thermal radiation ratios, and values of the temperatures T corresponding to the points are substituted into formulas to obtain m1 and m2 respectively.

Abstract: An apparatus and a method for online and real-time detection of a temperature of an epitaxial wafer (4) belong to the technical field of semiconductor detection. The apparatus comprises a MOCVD reaction chamber (1), a light source (6), a beam splitter (7), a reference light detector (8), a reflected light detector (9) and a data acquisition unit (10). The method, on the basis of the apparatus, can obtain a thermal radiation attenuation factor caused by a coating of a reactor chamber window and a reflectance attenuation factor caused by the coating of the reactor chamber window for the epitaxial wafer (4). The apparatus and method can eliminate influence of the coating of the reactor chamber window on an online and real-time temperature detection value, thereby improving the accuracy of the online and real-time temperature detection value.

Abstract: A device for detecting a two-dimensional morphology of a wafer substrate in real time. The device comprises: a first calculation module, a second calculation module and an analysis module, wherein the first calculation module calculates the curvature CX between any two points of incidence on the wafer substrate in an X direction of a substrate to be detected according to position signals of N light spots; the second calculation module calculates the curvature CY at any one point of incidence on the wafer substrate in a moving direction, i.e. a Y direction, of the substrate to be detected according to the position signals of N light spots. The device can be adapted to a sapphire substrate on a graphite disc which rotates at a high speed.

Abstract: An apparatus and a method for online and real-time detection of a temperature of an epitaxial wafer (4) belong to the technical field of semiconductor detection. The apparatus comprises a MOCVD reaction chamber (1), a light source (6), a beam splitter (7), a reference light detector (8), a reflected light detector (9) and a data acquisition unit (10). The method, on the basis of the apparatus, can obtain a thermal radiation attenuation factor caused by a coating of a reactor chamber window and a reflectance attenuation factor caused by the coating of the reactor chamber window for the epitaxial wafer (4). The apparatus and method can eliminate influence of the coating of the reactor chamber window on an online and real-time temperature detection value, thereby improving the accuracy of the online and real-time temperature detection value.

Abstract: A self-calibration apparatus and method for a real-time temperature measurement system of a MOCVD device belong to the technical field of semiconductor manufacturing. The apparatus comprises a MOCVD reactor chamber (1) and an optical detector (6). The MOCVD reactor chamber (1) comprises an epitaxial wafer (4). A detection window (5) is provided on the top of the MOCVD reactor chamber (1). The optical detector (6) emits detection light beams whose wavelengths are respectively ?1 and ?2 toward the epitaxial wafer (4) through the detection window (5). The detection light beams are reflected by the epitaxial wafer (4) to form reflected light beams which are detected by the optical detector (6). In the method, points corresponding to the actual thermal radiation ratios are depicted on the theoretical thermal radiation ratio-temperature curve according to actual thermal radiation ratios, and values of the temperatures T corresponding to the points are substituted into formulas to obtain m1 and m2 respectively.

Abstract: Disclosed is an apparatus for automatically and quickly detecting a two-dimensional morphology of a wafer substrate in real time. The apparatus may comprise: a first calculation module, a second calculation module and an analysis module, wherein the first calculation module calculates a curvature CX between any two points of incidence on the wafer substrate in an X direction of a substrate to be detected according to position signals of N light spots; the second calculation module calculates a curvature CY of any point of incidence on the wafer substrate in a moving direction, i.e., a Y direction of the substrate to be detected according to the position signals of the N light spots, wherein N is a natural number of 3 or more, and the N light spots are formed by N laser beams which are incident on the wafer substrate in a radial direction, i.e.