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CN-122003146-A - Two-in-one power semiconductor device

CN122003146ACN 122003146 ACN122003146 ACN 122003146ACN-122003146-A

Abstract

The invention provides a two-in-one power semiconductor device, which relates to the technical field of semiconductor devices and comprises a substrate, a wafer, a plastic package body, a plurality of power pins, a plurality of signal pins and a heat dissipation plate, wherein the wafer is arranged on the upper surface of the substrate, the power pins and the signal pins are electrically connected with the substrate and the wafer, the plastic package body packages the substrate and the wafer, the heat dissipation plate is arranged on the lower surface of the substrate, a cavity is arranged in the heat dissipation plate, and the cavity is filled with a heat conducting medium. According to the invention, after local heat generated by the wafer operation is transferred to the top wall of the cavity of the heat dissipation plate through the substrate, the heat can be quickly transferred to the heat conduction medium, the heat conduction medium forms natural convection due to regional temperature difference, so that uniform diffusion of the heat in the whole domain of the heat dissipation plate is realized, the formation of local hot spots by accumulation of the heat under the wafer heating region is avoided, the aging speed of the wafer is delayed, the whole service life of the device is prolonged, the working stability of the device under the working condition of high power density is improved, and the integrated application requirement of a vehicle-mounted heat management system is met.

Inventors

  • ZHANG LIANGJUN

Assignees

  • 爱微(江苏)电力电子有限公司

Dates

Publication Date
20260508
Application Date
20260129

Claims (10)

  1. 1. The two-in-one power semiconductor device is characterized by comprising a substrate (1), a wafer (2), a plastic package body (3), a plurality of power pins (4), a plurality of signal pins (5) and a heat dissipation plate (6), wherein the wafer (2) is arranged on the upper surface of the substrate (1), the power pins (4) and the signal pins (5) are electrically connected with the substrate (1) and the wafer (2), the plastic package body (3) encapsulates the substrate (1) and the wafer (2), the heat dissipation plate (6) is arranged on the lower surface of the substrate (1), a cavity is arranged in the heat dissipation plate (6), and a heat conducting medium is filled in the cavity.
  2. 2. The two-in-one power semiconductor device according to claim 1, wherein the pin directions of the plurality of power pins (4) are distributed on a first side surface or a first side surface and a second side surface of the substrate (1), the pin directions of the plurality of signal pins (5) are distributed on the second side surface of the substrate (1), and the first side surface and the second side surface are opposite to each other.
  3. 3. The two-in-one power semiconductor device according to claim 1, wherein the power pins (4) and the signal pins (5) are both right-angle bent structures.
  4. 4. The two-in-one power semiconductor device according to claim 1, wherein the plastic package (3) wraps the periphery of the substrate (1) and the outer side of the wafer (2).
  5. 5. The two-in-one power semiconductor device according to claim 1, wherein a temperature sensor is arranged on the substrate (1), the temperature sensor is electrically connected with at least two signal pins (5), and the temperature sensor is a negative temperature coefficient thermistor.
  6. 6. The two-in-one power semiconductor device according to claim 1, wherein an oil filling port (7) is formed in the side wall of the heat radiating plate (6), the oil filling port (7) is communicated with the cavity, an internal thread is formed in the inner wall of the oil filling port (7), a blocking bolt (8) is arranged in the oil filling port (7), an external thread matched with the internal thread is formed in the outer wall of the blocking bolt (8), and the blocking bolt (8) is in sealing connection with the inner wall of the oil filling port (7) in a threaded screwing mode.
  7. 7. The two-in-one power semiconductor device according to claim 1, wherein a plurality of support bars (9) are arranged in the cavity, the cavity is divided into a plurality of heat conducting cavities (10) by the plurality of support bars (9), the plurality of support bars (9) are distributed at equal intervals along the width direction of the substrate (1), the upper surface of the support bars (9) is connected with the top wall of the cavity, the lower surface of the support bars (9) is connected with the bottom wall of the cavity, a plurality of communication holes (11) are formed in the bottom of the support bars (9) in a penetrating mode, the plurality of communication holes (11) are arranged at equal intervals along the length direction of the support bars (9), and two ends of the communication holes (11) are respectively communicated with the heat conducting cavities (10) adjacent to two sides of the support bars (9).
  8. 8. The two-in-one power semiconductor device according to claim 7, wherein the heat conducting component is arranged in the heat conducting cavity (10), the heat conducting component comprises a heat conducting seat (12) and a connecting cylinder (13), the upper end of the heat conducting seat (12) is connected with the top wall of the heat conducting cavity (10), the heat conducting seat (12) is funnel-shaped, the lower end of the heat conducting seat (12) is provided with the connecting cylinder (13), the upper end of the connecting cylinder (13) is communicated with the inside of the heat conducting seat (12), a first limiting ring (14) is arranged in the connecting cylinder (13), the outer wall of the first limiting ring (14) is fixedly connected with the inner wall of the connecting cylinder (13), a push plate (15) is arranged below the first limiting ring (14), the outer wall of the push plate (15) is connected with the inner wall of the connecting cylinder (13) in an up-down sliding manner, the space above the connecting cylinder (13) is connected with the inner space of the heat conducting seat (12) to form a storage cavity (16), a heat conducting medium is stored in the storage cavity (16), the push plate (15) is connected with the top wall of the storage cavity (16) through a first spring (17), a fixed plate (18) is arranged below the push plate (15), a fixed plate (18) is fixedly connected with the inner wall of the connecting cylinder (13) along a plurality of through holes (19), a plurality of fixed through holes (19) are uniformly arranged along the first through holes, the fixed plate (19) and are fixedly connected with the first through holes, the center of the push plate (15) is provided with a liquid inlet pipe (20), the upper end of the liquid inlet pipe (20) is communicated with the storage cavity (16), the lower end of the liquid inlet pipe (20) passes through the fixed plate (18) and is communicated with the lower part of the fixed plate (18), and a one-way valve is arranged in the liquid inlet pipe (20).
  9. 9. The two-in-one power semiconductor device according to claim 8, wherein the lower end of the connecting cylinder (13) is connected with the bottom wall of the heat conducting cavity (10), the connecting cylinder (13) is provided with a plurality of liquid inlet holes (21) close to the outer wall of the lower end, and the liquid inlet holes (21) are distributed in an annular array relative to the central axis of the connecting cylinder (13).
  10. 10. The two-in-one power semiconductor device according to claim 8, wherein a sliding plate (22) is arranged below the fixed plate (18), the outer wall of the sliding plate (22) is connected with the inner wall of the connecting cylinder (13) in an up-down sliding manner, the upper surface of the sliding plate (22) is connected with the lower surface of the fixed plate (18) through a second spring (23), a second limiting ring (24) is arranged below the sliding plate (22) at intervals, the outer wall of the second limiting ring (24) is fixedly connected with the inner wall of the connecting cylinder (13), a plurality of second through holes (25) are uniformly formed in the side wall of the connecting cylinder (13) along the circumferential direction of the second through holes (25) and are positioned between the fixed plate (18) and the sliding plate (22).

Description

Two-in-one power semiconductor device Technical Field The invention relates to the technical field of semiconductor devices, in particular to a two-in-one power semiconductor device. Background With the development of new energy automobiles to high endurance and rapid charging, the demand of a vehicle-mounted thermal management system for integrated and miniaturized power semiconductor devices is increasingly urgent. E-Comp (electronic compressor controller) and PTC (positive temperature coefficient heater) are used as the vehicle-mounted heat management core components, and the problems of large occupied space, high wire harness loss, slow cooperative control response and the like exist in the traditional separated layout, so the industry gradually turns to the development of E-Comp and PTC two-in-one power semiconductor devices. The existing E-Comp and PTC two-in-one power semiconductor device has the advantages that the E-Comp and PTC are integrated, so that the power density of the semiconductor device is obviously improved, a large amount of heat is generated by a core power wafer of the semiconductor device in the working process, and the heat is often concentrated in a local high-power area of the wafer, so that the working stability and the service life of the device are directly determined by the heat dissipation performance. The heat dissipation function of the two-in-one power semiconductor device at present mainly depends on a substrate or a metal heat dissipation plate (such as an aluminum alloy and a copper-based heat dissipation plate) attached to the lower surface of the substrate, and the heat generated by a wafer is conducted to the whole heat dissipation plate by means of the excellent heat conductivity coefficient of a metal material and then dissipated to an external heat dissipation terminal. However, the heat conduction efficiency of the traditional metal heat dissipation plate is easily restricted by factors such as material uniformity, internal microstructure defects (such as air holes, cracks and loose grain boundaries) and the like, particularly, the alloy heat dissipation plate is extremely easy to generate component segregation phenomenon in the melt solidification process, so that alloy elements are unevenly distributed in different areas of the heat dissipation plate, and the concentration of the alloy elements at local positions is higher or lower. Because of the inherent difference of the heat conductivity coefficients of the metal matrixes formed by different components, the heat conductivity coefficients of the whole area of the heat dissipation plate are distributed unevenly. When the wafer generates heat in a concentrated manner, heat is transmitted along the direction with higher metal heat conductivity coefficient preferentially, so that the heat is difficult to diffuse to the whole area of the heat dissipation plate rapidly, the heat is accumulated continuously under the heat generation area of the wafer to form obvious local hot spots, the local hot spots continuously exist to cause the local temperature of the device to exceed a design threshold value, on one hand, the ageing of semiconductor materials in the wafer can be accelerated, the power conversion efficiency of the device is reduced, the service life of the device is shortened, on the other hand, the thermal stress of the heat dissipation plate and the substrate is uneven due to the overlarge local temperature difference, the bonding surface of the heat dissipation plate and the substrate is easy to peel, the heat dissipation performance is further deteriorated, and even the short circuit failure of the device is caused when the heat dissipation performance is serious. Disclosure of Invention The invention provides a two-in-one power semiconductor device, which is used for solving the technical problem that when a wafer of the existing semiconductor device generates local concentrated heat, heat is continuously accumulated under a wafer heating area to form obvious local hot spots. In order to solve the technical problems, the invention discloses a two-in-one power semiconductor device which comprises a substrate, a wafer, a plastic package body, a plurality of power pins, a plurality of signal pins and a heat dissipation plate, wherein the wafer is arranged on the upper surface of the substrate, the power pins and the signal pins are electrically connected with the substrate and the wafer, the plastic package body packages the substrate and the wafer, the heat dissipation plate is arranged on the lower surface of the substrate, a cavity is arranged in the heat dissipation plate, and a heat conducting medium is filled in the cavity. Preferably, the pin-out directions of the plurality of power pins are distributed on the first side surface or the first side surface and the second side surface of the substrate, the pin-out directions of the plurality of signal pins are distributed on the second side surface of