TWI446462B - Power module - Google Patents

Description

Power module

The invention relates to a power module, in particular to a power module applied to a power converter.

High efficiency and high power density have always been the industry's requirements for power converters. High efficiency means reducing energy consumption, saving energy and reducing emissions, protecting the environment and reducing the cost of use. High power density means small size, light weight, reduced transportation costs and space requirements, thus reducing construction costs; high power density also means reduced material usage, further conducive to energy saving and environmental protection. Therefore, the pursuit of high efficiency and high power density in the power supply field will never stop.

Power converters have many types due to their different uses. Divided by the type of converted electrical energy, it can be divided into: non-isolated AC/DC power converter, for example, consisting of an AC/DC converter circuit for power factor correction (hereinafter referred to as PFC circuit); non-isolated DC/ DC power converter; isolated DC/DC converter; isolated AC/DC power converter, for example, one PFC circuit plus one or more DC/DC converters; DC/AC, AC/AC, etc. . Due to the nature of the electrical energy that needs to be converted and the number of stages of conversion, the easily achieved power density and efficiency of the various converters are also different. Taking the isolated AC\DC power converter as an example, the current power density is 10w/inch ³ and the efficiency is about 90%. The efficiency and power density of non-isolated AC/DC power converters, isolated DC/DC converters, and DC/AC are higher.

As mentioned before, the high efficiency of the power converter means low energy consumption. If the efficiency is 90%, the conversion energy consumption is about 10% of the total input energy of the entire power converter. For a power converter with 91% efficiency, the conversion energy consumption is reduced to 9% of the total input energy. That is to say, for every point of efficiency improvement, the energy consumption is 10% lower than that of the 90% efficiency power converter, which is extremely impressive. In fact, efforts to increase the efficiency of power converters are often performed on the order of 0.5% or even 0.1%.

The power consumption of a power converter is mainly composed of on-state losses and switching losses, especially the switching losses of active devices. Switching losses are greatly affected by the operating frequency. Power converters, especially switching power converters, typically operate at frequencies above 20 kHz to reduce audio noise. The choice of its actual operating frequency is greatly affected by passive components, especially magnetic components. If the magnetic component is small in size, in order to work reliably, high frequency is usually required to reduce the working magnetic flux density to cause high switching loss; or to reduce the wire diameter of the wire group in the magnetic component and increase the number of turns, thereby increasing the on-state loss, Both bring high losses. Conversely, if the magnetic component is bulky, the operating frequency can be reduced to reduce the switching loss while ensuring reliable operation; the wire diameter of the wire group in the magnetic component can be increased or the number of turns can be reduced, thereby reducing the on-state loss and reducing Total loss, get high efficiency.

Therefore, it is not difficult to understand that improving the space utilization inside the power supply is one of the key factors for obtaining high power density or high efficiency. The higher the space utilization, the more space is left for passive components, especially magnetic components, which are important for power conversion efficiency, making it easier to use large-volume passive components, thereby improving power efficiency. It is also possible to increase the power density of the power converter by using a large volume of passive components to increase the total power of the power supply. Therefore, high power space utilization makes it easier to achieve high efficiency at a specific power density or achieve high power density at a specific efficiency, and also has the opportunity to combine high power density and high efficiency.

Semiconductor devices are one of the important factors determining the efficiency of power converters. But using semi-guide Body devices often require the use of additional materials that are not beneficial to the efficiency of the electrical conversion, such as: packaging materials that protect semiconductors, heat sinks that help dissipate heat, fixtures that hold semiconductor devices, and so on. The greater the proportion of these materials inside the power converter, the worse the internal space utilization of the power supply. Because of this, the power semiconductor device and the space volume actually occupied by it (hereinafter referred to as the space occupied by the power device) are more and more important.

The Integrated Power Module (IPM), because of the integration of multiple semiconductor devices in a single device package, offers the potential to increase space utilization within the package. However, existing power modules do not reduce the power device footprint, and are rarely used by high-performance power converters.

Therefore, in order to further improve the power density or conversion efficiency of the power converter, a power module solution with high space utilization and reasonable cost is needed. The current state of the art is not well met.

In view of the above problems, the present invention proposes a power module suitable for a power converter to improve power density or efficiency, and provides a power module implementation supporting the solution.

To achieve the above objective, a power module according to the present invention includes a first power device and a second power device, each of the power devices being encapsulated in the same sealing material, each of the power devices having at least two electrodes, the power At least one of the devices has at least three electrodes, and at least one of the power devices has an operating frequency above 25 kHz, wherein the power module is applied to a power converter, and at least one of the power devices has a high operating voltage inside the power converter to 48 volts, the power density and the maximum efficiency of the power converter are greater than 15w / inch ³ to 92% and above, the power converter or power density greater than 20w / inch ^3, or maximum efficiency of the power converter is higher than 93%, the power module accounts for less than 50% of the total volume of the power converter, and the power conversion stage processing power of the power module accounts for at least 30% of the total output power of the power converter, and the total output power of the power converter Above 150W.

The power converter is, for example, an AC/DC power converter, or an isolated DC/DC converter or a DC/AC converter. The power converter and the maximum efficiency of the power converter are greater than 20 w/inch ³ and higher than 93%, respectively. Or the power converter has a power density greater than 25 w/inch ³ or the highest efficiency of the power converter is greater than 94%.

In one embodiment, the power module further includes a first heat dissipating unit, a layer of thermally conductive insulating material, a lead frame, and a material. The first power device and the second power device are disposed above the first heat dissipation unit. The first heat dissipation unit has a first region and a second region, and the first power device is disposed in the first region. The layer of thermally conductive insulating material is disposed in the second region and has an insulating layer, and the second power device is disposed on the first heat dissipating unit by the layer of thermally conductive insulating material. The lead frame is electrically connected to at least one of the first power device and the second power device. The encapsulant encapsulates the first power device, the layer of thermally conductive insulating material, the second power device, and a portion of the leadframe.

In an embodiment, the power module further includes a third power device, a fourth power device, a lead frame, and a material. The third power device is disposed on the second power device, and the fourth power device is disposed on the first power device. The lead frame is located between the first power device and the fourth power device, and is located between the second power device and the third power device, and is located above the third power device and the fourth power device. The encapsulant encapsulates at least a portion of the power devices and lead frames.

As described above, since the power module of the present invention integrates a plurality of power devices, the power density or efficiency can be greatly improved. For example, the power converter and the highest efficiency of the power converter applied to the power module are respectively greater than 15 w/inch ^{3 .} And above 92%, or the power converter power density is greater than 20w/inch ³ , or the highest efficiency of the power converter is higher than 93%. The power converter can be an AC/DC power converter, or an isolated DC/DC converter, or a DC/AC converter. The power converter and the highest efficiency of the power converter can be greater than 20 w/inch ³ and higher than 93%, respectively. Or, the power converter has a power density greater than 25 w/inch ³ or the highest efficiency of the power converter is greater than 94%. And at least one of the power devices operates at a frequency above 25 kHz. The power module is applied as a component to a power converter, and the power module accounts for less than 50% of the total volume of the power converter to be applied. The power module is applied as a power component to a power converter. The power conversion stage processing power of the power module accounts for at least 30% of the total output power of the power converter, and the total output power of the power converter is 150 W or more. The power module is suitable for application to a relatively complicated system in order to improve a higher space utilization, such as an AC/DC power converter, or an isolated DC/DC converter or a DC/AC converter. The power converter typically has an operating voltage of at least one power device above 48 volts. In the case of an AC/DC power converter, the power converter typically has an operating voltage of at least one power device above 200 volts.

In addition, since the first power device of the present invention is not disposed on the heat dissipation unit by the heat conductive insulating material layer, the cost of the heat conductive insulating material layer can be reduced. In addition, the packaging method and structure for improving the power density or efficiency of the power converter disclosed by the present invention can obtain better thermal performance, electrical performance, economic performance, EMC performance and higher than the prior art. Reliability. Its internal space utilization is very high and easy to use, which is very beneficial to improve converter power density or efficiency. The specific implementation of the specific power module given by the present invention is also very feasible and effective. The invention is well suited for improving the overall performance and cost performance of a power converter.

In addition, the power module of the present invention stacks the plurality of power devices together, which can reduce the connection line to reduce the on-state loss, reduce the high-frequency impedance, and reduce the switching loss. Improve power performance in one step. Moreover, for bridge circuits, including half bridges, full bridges, three-phase bridges, etc., after stacking, some materials originally used for insulation are not needed, which can save cost, improve space utilization, and further improve power converter performance.

10‧‧‧Power Module

11, 11a, 11b, 11c‧‧‧ heat sink

111‧‧‧First District

112‧‧‧Second District

12‧‧‧First power device

13‧‧‧ Thermally Conductive Insulation Layer

131‧‧‧thermal layer

132‧‧‧Insulation

133‧‧‧Line layer

13a‧‧‧ copper substrate

14‧‧‧second power device

15‧‧‧ lead frame

16‧‧‧Filling

17‧‧‧bonding material layer

18‧‧‧Control device

19a‧‧‧ Third power device

19b‧‧‧fourth power device

A1‧‧‧ front surface

A2‧‧‧ rear surface

B‧‧‧Board

C‧‧‧ capacitor

D‧‧‧thickness

IL‧‧‧Insulation

P2, P1‧‧‧ pin

S1~S4‧‧‧ Switching Devices

T‧‧‧ Height

W‧‧‧Wire

1 is a schematic diagram of a power module according to a preferred embodiment of the present invention; FIGS. 2 and 9 show different aspects of a full bridge circuit of a power module application according to a preferred embodiment of the present invention; and FIGS. 3 to 8. 10 to 22 are schematic views of different aspects of a power module according to a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION A power module in accordance with a preferred embodiment of the present invention will be described with reference to the accompanying drawings, in which the same elements will be described with the same reference numerals.

Referring to FIG. 1 , a power module 10 according to a preferred embodiment of the present invention can be applied to, for example, a power converter or other device that requires power conversion, and a power source applied to the power module 10 . maximum efficiency and power density of the inverter are greater than 15w / inch ³ and greater than 92%, or greater than the power density of the power converter 20w / inch ^3, or maximum efficiency of the power converter of higher than 93%. The power converter can be an AC/DC power converter, or an isolated DC/DC converter, or a DC/AC converter. The power converter and the maximum efficiency of the power converter are greater than 20 w/inch ³ and higher than 93%, respectively. Or the power converter has a power density greater than 25 w/inch ³ or the highest efficiency of the power converter is greater than 94%. Alternatively, the power converter can be an AC/AC converter. If the power converter is applied to an AC/DC power converter, the power module 10 can be applied to a power factor correction (PFC) of the power converter, a DC/DC primary side portion (hereinafter referred to as D2D_Pri), or DC/DC secondary side part (hereinafter referred to as D2D_Sec). The power module 10 occupies less than 50% of the total volume of the power converter, and the power conversion stage processing power of the power module accounts for at least 30% of the total output power of the power converter, and the total output power of the power converter is above 150W. At least one of the power devices within the power converter has an operating voltage greater than 48 volts.

The power module 10 is a package including a plurality of power chips, such as a first power device 12 and a second power device 14. At least one of the first power device 12 and the second power device 14 operates at a frequency above 25 kHz to improve power conversion performance. The power module 10 includes a first heat sink 11 , a thermal conductive material layer 13 , a lead frame 15 , and a power module 10 . Molding material 16. The first heat dissipating unit 11 is disposed on one side of the package body and has a first area 111 and a second area 112. The first power device 12 and the second power device 14 are disposed above the first heat dissipation unit 11 . The first power device 12 is disposed in the first region 111 , and the thermal conductive material layer 13 is disposed in the second region 112 . The second power device 14 is disposed on the thermally conductive insulating material layer 13 and electrically connected to the lead frame 15 . The sealing material 16 covers at least a portion of the first power device 12, the thermally conductive insulating material layer 13, the second power device 14, and the lead frame 15, and is configured as a main appearance of the package. The first power device 12 and the second power device 14 are enclosed in the same seal 16. The first power device 12, or the second power device 14, has an operating voltage of at least one power device internal to the power converter that is greater than 48 volts.

The first heat dissipating unit 11 may be a separate component or integrally formed with the lead frame 15, and may be a good conductor of electricity and heat, such as copper. Here, the heat dissipation unit 11 serves as a carrier of the first power device 12. The first heat dissipating unit 11 may be completely disposed in the sealing material 16, or a portion of the material outside the sealing material 16, or completely outside the sealing material 16. In addition, the first heat dissipation unit The thickness of 11 may be greater than 20% of the thickness of the power module 10 and less than 3 mm. After good heat transfer is ensured, heat is transferred from the power device to the heat sink unit, and then transferred from the heat sink unit to each direction to help achieve thermal uniformity in all directions. Then, the heat dissipating unit needs to have a certain thickness in order to support the lateral transfer function. The invention proposes that the thickness of the heat dissipation unit is greater than 20% of the thickness T of the power module. Since the heat dissipating unit is a good conductor, in the case of copper, the thermal conductivity can reach 400 W/m.K. If the thickness accounts for more than 20% of the whole, it means that the average power of the lateral heat transfer in the section of the entire power module is 400W/mK x20%=80W/mK, which is more conducive to the lateral transfer of heat. . The higher the ratio, the better the lateral thermal conductivity, and the easier to achieve thermal uniformity; the high ratio also means that the proportion of relatively non-heating conductors such as sealing materials is low, the thickness is thin, and it is easier to heat the heat sink unit to the tropical The surface of the power module for heat exchange with surface fluids. That is to say, under the premise that the width of the heat dissipating unit is constant, the larger the thickness, the easier it is to have a large cross-sectional area, and the larger the overall proportion, the stronger the heat transfer capability. In reality, however, the thickness of the heat sink unit is balanced against factors such as overall thickness and cost. For example, the total thickness is less than 6 mm, and the thickness of the heat dissipating unit is preferably not more than 3 mm. Based on the foregoing, the thickness of the power module is preferably more than 20%. This is more beneficial for achieving the above-described double-sided heat dissipation characteristics.

The first power device or the second power device has at least two electrodes, at least one of which has at least three electrodes, for example the first power device 12 and/or the second power device 14 has at least three electrodes. A power device is, for example, a device of a metal oxide semiconductor field effect transistor (MOSFET). For a device of one MOSFET, it typically has two relatively parallel faces: an upper surface and a lower surface. Two electrodes are often disposed on the upper surface: a source and a gate, and a lower surface electrode is a drain, and a lower surface is directly connected to the first heat dissipation unit 11 by using a bonding material layer 17 The bonding, bonding material layer 17 may comprise soldered solder, conductive silver paste, or sintered metal material or the like.

Such bond materials have a high thermal conductivity (typically not less than 2 W/m.K), and the thickness of this layer can be controlled to be relatively thin (e.g., below 200 um, typically below 100 um). Therefore, the conduction thermal resistance between the power device 12 and the first heat dissipation unit 11 can be controlled to be relatively low. For example, the bonding material layer 17 has a thermal conductivity of 20 W/m·K, a thickness of 100 μm, an area of 10 mm square, and a thermal resistance of 0.05 K/W. The conduction heat resistance of the first heat dissipation unit 11 itself is usually also very low, so that the thermal resistance (Rjc) of the very low device node to the outer casing of the first heat dissipation unit 11 can be obtained, and, due to the first heat dissipation unit 11 The heat capacity is large, and therefore, the thermal shock resistance of the power device is also excellent. In summary, the thermal performance of the first power device 12 directly assembled to the first heat dissipation unit 11 is very excellent. Moreover, due to the presence of the first heat dissipation unit 11, the heat of the power module 10 is relatively uniform, which is more favorable for thermal management. Of course, only the power device is taken as an example here.

Since the package type of the embodiment is internal for power supply, in order to achieve higher space utilization and improve the performance of the power module 10, the module surface does not need to be completely electrically insulated from the internal circuit. In order to reduce the insulation cost and the space waste caused by the insulation, the heat dissipation capability is attenuated and the like. Therefore, in some specific occasions, the first heat dissipating unit 11 can be directly used as a conductive path. Since the first heat dissipating unit 11 is generally an excellent conductor of copper, aluminum, etc., and has a relatively thick thickness (usually not less than 0.5 mm), Excellent electrical conductivity. Therefore, it is possible to obtain better electrical performance and reduce heat generation, thereby further improving the thermal performance of the package. Further, the first heat dissipation unit 11 can be directly used as a pin (Pin) or connected to at least one pin, that is, the pin can be integrally formed with the first heat dissipation unit 11, or the pin and the first heat dissipation. The unit 11 achieves good wire bonding, soldering, soldering, conductive bonding, and the like. Electrically connected to make better use of the good electrical conductors of the surface. This greatly reduces the thermal resistance of the device to the first heat dissipating unit 11, and also enables the electric heat conductor of the first heat dissipating unit 11 to be simultaneously exposed to heat and electricity. Thereby improving the space utilization, in order to facilitate the power converter power density or conversion efficiency.

In addition, the power module 10 has a thickness D of 6 mm or less. Due to the current power demand, it is hoped that the overall thinner the better, an industrial unit thickness (1U), about 44.45mm thick, for the future power supply trend. As shown in FIG. 21, the power module 10 is mounted on a circuit board (PCB) B, and the height T of the highest point from the surface of the circuit board B is 35 mm or less. At the same time, in order to use the internal space of the power supply as much as possible, the height of the power module should not be too low, and the height is preferably used at a height of more than 60% of the highest point. For example, the highest point of the power module 10 is away from the upper surface of the circuit board B. The distance is preferably higher than 35 mm x 60% = 21 mm. In this embodiment, the pins of the power module 10 extend from below the power module 10 and stand upright on the circuit board B. The power module 10 is a direct-insertion type package (such as SIP or DIP). In addition, FIG. 22 shows an application case sectional view size of a power module 10 of the present invention. The thickness of the heat dissipating unit 11 is preferably 20% or more of the total thickness of the power module 10. For example, the thickness of the heat dissipating unit 11 (Cu) is 1.5 mm, which is about 32.6% of the total thickness, which is greater than the desired 20 %, so it has better heat uniformity. The front surface A1 of the sealing material 16 has a design distance of 0.24 mm from the highest point of the wire W, which is less than the desired 0.5 mm, so that the power device (Die) 12, 14 has the ability to transfer energy to the front surface of the sealing material 16. The sealing material 16 is 1.24 mm away from the thinnest part of the upper surface of the power device (ie, the front surface of the sealing material A1 to the upper surface of one of the power devices 12 or 14), and the actual average thickness is less than 2.5 mm, which satisfies the expectation of less than 3 mm, and Meet less than 55% of the total thickness and meet the desired 60% requirement. The embodiment has good double-sided heat dissipation capability, and has strong self-heat dissipation capability, no reserved screw holes, and higher space utilization. The total thickness of the power module 10 shown in FIG. 22 is 4.6 mm, which is sequentially 0.24 mm (front Surface A1 to wire W highest point), 1.0 mm (wire W height), 0.175 mm (device 12, 14 thickness), 0.05 mm (solder thickness), 0.5 mm (lead frame 15 thickness), 0.05 mm (solder thickness), 1.03mm (thickness of thermal conductive material layer 13), 0.05mm (solder thickness) and 1.5mm (heat dissipation unit 11).

In the experiment for outputting communication power with 2700W AC/DC 48V, since this embodiment is much more obvious than the prior art, the DC/DC grade magnetic component is changed from the original smaller PQ32/30 to PQ35/35, thereby The operating frequency has been reduced from the original 100 kHz to 65 kHz, and the efficiency has increased by more than 0.5%. Similarly, the PFC-class magnetic component is converted from the original PQ35/35 to PQ40/40, so that the operating frequency will be 45 kHz from the original 70 kHz, and the efficiency is improved by more than 0.3%. Moreover, due to the decrease of the frequency, the driving loss is also significantly reduced, and the power consumption of the fan can also be reduced due to the increase in efficiency, thereby causing the auxiliary power loss to be greatly reduced, and the efficiency can be improved by 0.2%. Due to the power module, multiple devices are integrated internally, and the path is optimized. The DC impedance and AC impedance are reduced, and the direct contribution to efficiency is 0.1%. As a result, the actual overall efficiency improvement is close to 1%, which is very impressive. These are mainly due to the fact that the embodiment of the power module greatly improves the space utilization.

As described above, the power module is particularly suitable for use in a high performance power converter having a power density and a maximum efficiency greater than 25 w/inch ³ and greater than 95%, respectively, or the power of the power converter. The density is greater than 30w/inch ³ , or the maximum efficiency of the power converter is higher than 96%.

Full-bridge circuits are extremely common in applications such as the primary or secondary side of the transformer. Therefore, the power module 10 of the present embodiment can be used in a full bridge circuit. 2 is a schematic diagram of a full-bridge circuit. To satisfy this application, the power module 10 must be capable of arranging at least eight function pins, namely, Vin, GND, VA, VB, G1, G2, G3, and G4. Due to typical applications, the voltage between Vin, GND, VA, and VB pins can reach 400V. The edge distance is preferably 2~3mm, and G1 to VA, G2 to VB, G3 to GND, G4 to GND, the voltage is lower, 30V or less, and the insulation distance between pins is 0.5~1mm, the pin itself The width can be designed to be 0.5~2mm. In some cases, it is necessary to integrate a temperature sensor and other devices. At least 2 pins need to be reserved for standby. In this way, the package width of the power module can be preferably less than 6 cm.

In order to further improve the performance of the power module 10 and fully exploit the potential, the power module 10 has a double-sided heat dissipation capability. The double-sided heat dissipation capability is defined as follows: a uniform constant velocity air fluid in a large enough space, no additional heat sink is provided on both surfaces of the power module, and the power module is placed in a large enough space to directly face the air, two The surface is parallel to the air fluid; the heat dissipation capability of the two surfaces is not more than 1 time, that is, the heat dissipation capability of any surface is not less than 1/3 of the sum of the two surfaces.

In this embodiment, the two largest main surfaces of the power module, a front surface (sealing material 16) A1 and a rear surface (heat dissipating unit 11 and sealing material 16) A2, can be used for heat dissipation. For example, in a 5m/s balanced wind speed parallel wind cooling environment, the front surface A1 and the rear surface A2 of the power module 10 are at least 80% of the area, and the maximum temperature difference between the points is less than the average temperature rise of all the surfaces relative to the working environment. 20%. In this way, the effective heat dissipation capability can be greatly increased, and it is easier to dissipate heat in a low-loss situation without an additional heat sink, thereby greatly improving the internal space utilization of the power supply. In order to achieve better heat dissipation characteristics, the thinner the thickness of the sealing material, the better. For example, the minimum spacing between the upper surface of the sealing material 16 and the upper surface of the wafer is preferably controlled to be less than 0.5 mm. In addition, the average thickness of the seal 16 is less than 60% of the thickness of the power module 10 and less than 3 mm. Here, the average thickness of the sealing material 16 is defined as follows: as shown in Fig. 1, the total volume of all the sealing materials 16 of the power module is divided by the main area formed by the height T of the main body and its width (not shown), and the power is obtained. The average thickness of the module seal 16.

In order to facilitate double-sided heat dissipation, the power module is applied in the installation manner as shown in FIG. It is better for power converters. That is, the power module is a direct insertion type package (such as single in-line SIP or dual in-line DIP) to facilitate heat exchange between the two main surfaces and the environment, and it is easier to achieve double-sided heat dissipation.

In the state where the wind flow rate and the air flow temperature have been set first, the surface average temperature is determined by the surface heat exchange capacity. The average temperature is defined as follows: the surface is divided into several micro-aliquots, and the respective areas of all the micro aliquots are multiplied by the respective temperatures, and the products are all added together (ie, the integral of the surface temperature); the addition result is divided by The total surface area is the average temperature of the surface. The higher the average temperature, the higher the heat dissipated. When the amount of heat that needs to be dissipated is certain, it means that the average temperature must be determined within a certain range. If the surface heat distribution is desired to be as uniform as possible, it means that the highest temperature point is lower, which is more advantageous and low power device. The junction temperature allows the device to operate reliably and with better performance.

In addition, the above-mentioned average temperature rise of a surface region is defined as follows: the average temperature of the surface region is obtained according to the definition of the surface average temperature; the temperature of the fluid entering the region and the temperature of the fluid exiting the surface are divided by 2 to obtain the The average temperature of the fluid in the region; the average temperature of the surface region minus the average temperature of the fluid in the region is the average temperature rise of the surface region.

In order to reduce the mechanical stress during use, so that the module can be designed to be thinner, the power module does not have to be preset with a screw mounting hole. To further improve space utilization. If you need to install additional heat sinks, you can choose a screwless solution, such as direct bonding.

In this way, the power module 10 of the embodiment will greatly increase the amount of the package of the type, and is also in line with the current and future power converter requirements, and can improve the space utilization of the power converter, thereby increasing the power density of the power source. Or efficiency.

In addition, referring to FIG. 1 , the second power device 14 is disposed on the heat dissipation unit 11 by a thermal conductive material layer 13 instead of being directly disposed on the heat dissipation unit 11 . Thermal conductivity The edge material layer 13 may have an insulating layer 132, such as insulated with a ceramic sheet. In order to ensure the heat dissipation capability, the thermal resistance of the thermal conductive material layer 13 above and below the 10×10 area should be less than 3K/W. The thermally conductive insulating material layer 13 is, for example, a metal substrate or a metallized ceramic substrate, such as a direct bonded copper (DBC), a thickened copper circuit layer on a metallized ceramic sheet, a directly bonded aluminum (DBA), Aluminum substrate, copper substrate, or other form of highly thermally conductive substrate. The thermally conductive insulating material layer 13 is exemplified by the DBC substrate. The thermally conductive insulating material layer 13 can include a heat conducting layer 131, an insulating layer 132, and a wiring layer 133. The heat conducting layer 131 and the wiring layer 133 can be copper and the insulating layer 132. Can be ceramic.

Taking a conventional DBC substrate as an example, compared with the prior art, since only a part of components (second power device 14) can be mounted on the heat conductive insulating material layer 13, the number of components mounted thereon is reduced. The DBC substrate area can also be reduced accordingly, which can reduce the material cost of the package and improve the economic performance of the package. Moreover, because the DBC substrate area is reduced, the warpage phenomenon caused by the inconsistency of the coefficient of thermal expansion (CTE) between the sealing material 16 due to the DBC substrate and the heat dissipating unit 11 is also alleviated. . This is because the deflection due to mismatch between CTEs of different materials generally increases as the size increases. In this way, the stress in the package can be reduced, thereby further improving the reliability of the package. Therefore, since some devices (the first power device 12) have been directly connected to the heat dissipating unit 11, compared with the prior art, the power module of the present invention requires a significantly reduced material for insulation, which not only reduces the cost, but also improves the thermal management capability. It is also more conducive to reducing the reliability of the design caused by the mismatch of CTE of each material.

In practical applications, there are some occasions where the heat dissipation requirements are very demanding, and it is also possible to use a higher thermal conductivity (not less than 1 W/mK, especially greater than 1.2 W/mK or even greater than 1.8 W/mK). In this way, the heat dissipation capability on the side of the sealing material can be increased. Thereby achieving better double-sided heat dissipation, further improving the heat dissipation capability of the entire package.

FIG. 3 is another extended application of the package type, in which the surface of the heat dissipation unit can be insulated, so that the first heat dissipation unit 11 is completely covered by the sealing material 16 so that either surface is not exposed or is insulated by an insulator. The heat dissipating unit 11 is isolated from the outside for use in applications where insulation is desired. In order to ensure the heat dissipation capability, the thermal resistance of the insulator or the sealing material 16 in the upper and lower areas of 10 mm×10 mm should be less than 3 K/W.

In order to expand the package type of the power module to more occasions, it can be designed as a double row of Pin. As shown in Figure 4. When the internal circuitry is too complex to require more pins, a row of pins P2 can be added to the previously mentioned features. If such a package type is used where a single row of pins P1 is sufficient, the upper row of pins P2 in the figure can be designed for heat dissipation purposes. For example, the sum of heat dissipation via pin P2 is greater than or equal to 5% of the total heat dissipation of power module 10. In addition, in order to ensure that it can effectively help to dissipate heat, the average temperature difference between the environment and the environment is higher than the average temperature difference between the two surfaces before and after the actual temperature. The difference in temperature difference should not exceed 50%. It is well known that the more voltage jump points inside the power supply, the stronger the electromagnetic radiation is, which makes the electromagnetic compatibility of the power supply difficult. Since the heat dissipating unit 11 of the present invention has electrical characteristics and a relatively large area, it has a hidden danger to electromagnetic radiation. However, if the electrical characteristics of the heat dissipating unit 11 are optimized, the organic layer will be designed as a shielding layer for electromagnetic radiation, which is more advantageous for electromagnetic compatibility. For example, the heat dissipating unit 11 can be connected to a voltage static place, that is, relatively speaking, the potential is relatively quiet and less noise relative to the earth. As shown in Figure 2, Vin and GND are relatively quiet compared to other voltage points. Designing the heat sink unit 11 to be Vin or GND is more advantageous for electromagnetic compatibility. However, in actual operation, in order to facilitate the implementation, the surface on which the power device and the heat dissipation unit 11 are connected is required to have only one electrode, which is the first power device in this embodiment. 12. For example, in a MOSFET, the voltage between the drain and the source is often higher than the voltage between the gate and the source, so the source and the gate of the device often share one side. And the drain tends to be exclusive. In this way, the power device (the first power device 12) having the drain as a static place is directly connected to the heat dissipation unit 11, which can better perform electromagnetic compatibility and facilitate the process. As shown in Fig. 5, the heat dissipating unit 11 on the back side can be widened/long, or even bent, so that it partially exceeds the portion covered by the sealing material 16 to enlarge the surface area. The heat exchange with the environment can be achieved on both sides of the heat dissipating unit 11 covered by the sealing material 16. Therefore, the heat dissipation performance of the power module 10 can be further enhanced.

As shown in Fig. 6, in some cases, not only some power semiconductor devices need to be mounted inside the package, but also some control functions need to be integrated. Control lines are often complex, so you need to use a substrate with a higher wiring density, such as a PCB or IC. In this aspect, the control device 18 on which the control line is mounted, such as a high-density wiring board or a control IC, can also be packaged into the package.

As shown in FIG. 7, the control device 18 may be a high density substrate having a low thermal conductivity but a high wiring density. So that you can integrate more control functions. The control device 18 typically has a lower temperature rating than the temperature rating of the power device, and therefore a thermal barrier (thermal conductivity typically below 0.5 W/m.K) IL is placed between the control device 18 and the heat sink unit 11. In this way, the temperature of the control device 18 and the devices mounted thereon can be reduced.

As shown in FIG. 8, the heat dissipating unit 11 is not limited to a whole block, and may be further divided as needed to form some circuit patterns, that is, the heat dissipating unit 11 may have a plurality of electrodes. This can further increase the flexibility of the power module design.

Since the power module 10 integrates multiple devices, the current circulation loop is greatly reduced compared to the discrete device, thereby reducing the loop inductance, that is, reducing the loss and reducing the voltage noise. But still can continue to be optimized. As shown in Figure 9, with the full bridge mentioned For example, the circuit adds an integrated high-frequency capacitor C to the inside of the power module 10 to further reduce the loop and reduce the loop inductance.

Generally, the power converter monitors the temperature state of the power semiconductor in time for safety and reliability. If the temperature is too high or the temperature rises too fast, the circuit is dangerous, and preventive actions such as turning off the power can be taken in advance. The temperature detection of discrete devices can only increase the temperature sensor outside of it, so the internal temperature state cannot be reflected in time, and the temperature sensor installation is also complicated. Therefore, in the power module, the temperature sensor can also be integrated, which not only improves the temperature monitoring effect, but also simplifies the use.

As shown in FIG. 10, the power module of this aspect further includes a second heat sink 11a disposed between the second power device 14 and the layer of thermally conductive insulating material 13. Since the power device is subjected to a transient impact that is more than several times the normal operating current during operation, the second heat dissipating unit 11a can be used without increasing the area of the thermally conductive insulating material layer 13 (DBC substrate). Improves the thermal shock resistance of components that are subjected to thermal shock on the DBC substrate. Further, the lead frame 15 is extended to be connected to the wiring layer 133 of the thermally conductive insulating material layer 13.

As shown in FIG. 11, in order to further improve the thermal shock resistance of the element (for example, the second power device 14) which generates a large amount of heat on the thermally conductive insulating material layer 13 (for example, the DBC substrate), and further improve the line on the DBC substrate. The ability to carry current (because the thickness of the copper layer on the DBC substrate is affected by the DBC molding process, generally less than 0.5mm, usually not higher than 0.3mm), reducing the current conduction impedance, and the lead frame 15 The area is increased and bonded to the wiring layer of the DBC substrate by a conductive material. A physical photograph of a power module developed using this structure is shown in Figure 12 (unsealed). The thermally conductive insulating material layer 13 is soldered to the first heat dissipating unit 11 by means of soldering, and the lead frame 15 is also electrically and mechanically connected by means of soldering and the wiring layer of the thermally conductive insulating material layer 13. Used by the power module 10 shown in FIG. The DBC substrate has a wiring layer thickness of 0.3 mm, and the lead frame 15 has a thickness of 0.5 mm. Therefore, the conduction resistance of the structure is reduced by 60% or more compared with directly bonding the wafer to the DBC substrate wiring layer. It can effectively reduce the heat production of the module, thereby improving the electrical performance of the module and improving the heat dissipation performance of the module.

As shown in FIG. 13, in addition to the DBC substrate having a good thermal conductivity, a substrate having a better thermal conductivity such as a copper substrate 13a can be used in the power module 10. Generally, the structure of the copper substrate is such that an insulating layer and a thin copper wiring layer are formed on a thick copper substrate. Further, the number of layers of the insulating layer and the thin copper wiring layer is not limited to one layer, and may be a plurality of layers. Higher wiring densities can be achieved in some cases.

Generally, the first power device and the second power device both transmit signals by wire bonding, and since the wires are often completed by aluminum wires, the internal resistance is large. With gold wire (Au wire), the cost is too high. Although the recent process has a copper wire (Cu wire), it still has a large internal resistance. As shown in FIG. 14, in order to further reduce the loss caused by the internal resistance of the package, the present invention can realize the current transfer by using a wire bond process, such as a copper piece instead of wire bonding, which greatly reduces the internal resistance of the package, and the cost is not It will be too high. This aspect replaces the wires by extending the lead frame 15 to at least one of the first power device 12 and the second power device 14.

Figure 15 shows a solution for further improving heat transfer capability. Due to the power module mentioned in the present invention, some devices (for example, the first power device 12) are directly connected to the heat dissipation unit 11 to improve electrical performance and thermal performance, and some devices (for example, the second power device 14) and the heat dissipation unit. Between 11 there are insulating elements (for example, the layer of thermally conductive insulating material 13 having an insulating layer), resulting in uneven thickness of the sealing material 16 in the entire module, that is, the distance between the partial sealing material 16 and the device is relatively thick. The temperature of the sealing material 16 is made non-uniform, thereby affecting the heat dissipation capability of the surface of the sealing material 16. In Figure 15, in the seal 16 The thick place adds one of the heat-conducting conductors, the third heat-dissipating unit 11b, which is disposed in the first region of the first heat-dissipating unit 11, from the uniformizing of the sealing material 16 to the thickness of the device, to improve the heat dissipation capability.

In addition, as shown in FIG. 18, the third heat radiating unit 11b passes through the sealing material 16 and has a bent portion. The third heat dissipating unit 11b passes through the sealing material 16 and can be used as a pin (Pin), or simply dissipates heat, or partially serves as a pin portion for heat dissipation. The third heat dissipating unit 11b can reduce the size of the power module 10 when standing up by bending, and the total length from the package component to the apex should not be longer than 20 mm, especially not longer than 10 mm.

In practical applications, if the heat dissipation capability needs to be further expanded, it can be achieved by the method of FIG. That is, a fourth heat dissipation unit 11c is further mounted on the third heat dissipation unit 11b of the power module 10. The fourth heat dissipation unit 11c can be coupled to the third heat dissipation unit 11b by soldering, bonding, or the like. Since the shape and position of the fourth heat radiating unit 11c are simple to install, it is not limited. However, in actual effect, it is preferable to retain the surface heat dissipation capability of the power module 10. That is, as shown in FIG. 19, a gap is left between the fourth heat dissipating unit 11c and the front surface A1 of the power module 10, so that the wind flow can flow in the gap, thereby making the front surface of the power module and the lower surface of the fourth heat dissipating unit 11c ( Close to the surface of the front surface A1) can play a certain heat dissipation function. In order to achieve a considerable degree of wind flow in the gap, the gap thickness may be greater than 1 mm, especially greater than 2 mm.

In addition, as shown in FIG. 20, the power module 10 further includes a third power device 19a, a fourth power device 19b, a lead frame 15, and a material 16. The third power device 19a is disposed on the second power device 14, the fourth power device 19b is disposed on the first power device 12, and the first power device 12 and the second power device 14 are disposed on the heat dissipation unit 11. The lead frame 15 is located between the first power device 12 and the fourth power device 19b and between the second power device 14 and the third power device 19a and is located above the third power device 19a and the fourth power device 19b. Sealing material 16 covers the work Rate devices 12, 14, 19a, 19b and at least a portion of leadframe 15. By stacking multiple power devices together, the connection line can be reduced to reduce the on-state loss, the high-frequency impedance can be reduced, the switching loss can be reduced, and the power supply performance can be further improved. Moreover, for bridge circuits, including half bridges, full bridges, three-phase bridges, etc., after stacking, some materials originally used for insulation are not needed, which can save cost, improve space utilization, and further improve power converter performance.

In order to better explain the meaning of the present invention, further description is made by means of a full bridge circuit. As described above, FIG. 2 is a topology diagram of a full bridge circuit, and FIG. 16 and FIGS. 17A to 17D are respectively a power module internal structure and Three-dimensional schematic. 17A is a front view of the power module 10, FIG. 17B is a rear view of the power module 10, FIG. 17C is a front view of the power module 10 with the sealing material 16 removed, and FIG. 17D is a power module 10 A schematic view of the back side of the material 16.

Although the foregoing embodiment is described by taking a first power device 12 and a second power device 14 as an example, it is not limited, and wherein the first power device 12 represents the meaning of being disposed on the heat dissipation unit 11 . The meaning of the second power device 14 is that it is disposed on the heat dissipation unit 11 by a layer of thermally conductive insulating material 13. The following description will be made with two switching devices S1 and S2 and two switching devices S3 and S4.

As shown in FIG. 2, the full bridge circuit includes four switching devices S1 to S4, and a metal oxide semiconductor transistor is taken as an example here. The four switching devices form two sets of conductive bridge arms: S1 and S4 form a group, and S2 and S3 form a group of bridge arms; the drain terminals of the upper and lower tube switching devices S1 and S2 are connected in common at a voltage high potential point Vin (in In D2D application, the electrical terminal Vin is the DC input terminal, and the voltage waveform is a stable DC or a DC with a small ripple. The source terminals of the bridge lower tube switching devices S3 and S4 are connected together at the low potential point of the voltage. GND; the source of the upper arm of the single bridge arm is connected to the drain of the lower tube. For example, the S1 and S4 bridge arms are connected to the VA, and the bridge arms of the S2 and S3 are connected to the VB. The principle is that the upper and lower tubes of the bridge arm are complementarily turned on, such as S1 is turned on, S4 is turned off; S1 is turned off, and S4 is turned on, and there is a process in which the switching state transition process is turned off for a short time. Thus, in the application of D2D, the input terminal Vin-GND is DC, and the bridge arm intermediate connection point VA, VB voltage is the switching times of the transition, the amplitude is 0 and Vin.

At present, the most typical electrode extraction method of a high-power transistor is that the back side of the wafer is a drain, and two electrodes are arranged on the front side: a source and a gate, wherein the gate has a small size, for example, 1 mm*1 mm. The drain on the back side of the wafer is usually soldered in advance, and the source and gate of the front side are often aluminum metallized electrodes, which can be connected to peripheral circuits by aluminum/gold wire bonding. Since the drains of the switching devices S1 and S2 are connected to the common DC potential point Vin, they can be directly soldered to the heat dissipation unit 11, and the pins electrically connected to the outside and the external electrodes can be directly soldered to the heat dissipation unit 11. Therefore, the heat dissipation unit 11 with the conductive electrode is electrically conductive, which reduces electrical loss and reduces heat generation of the package. In this way, the best thermal and electrical properties can be obtained. For the existing power module, as described above, all four power transistors are mounted on the DBC substrate, and then the electrical connections of all the power transistors and the lead frame are realized by wire bonding. As discussed above, the various deficiencies of the prior art (poor heat dissipation, poor electrical performance, high price, poor reliability, etc.) are relatively straightforward.

The application of the invention here has the effect of reducing EMI, and the foregoing analysis of the basic working principle of the full bridge circuit. The heat dissipating unit 11 is connected to the DC input terminal Vin, which is a good static potential point, and the intermediate connection points VA and VB of the bridge arm are voltage jump points, and the large heat dissipating unit 11 can effectively block the transmission of the hopping signal. In this way, the interference of the trip point to the peripheral circuit can be effectively reduced, and the EMI of the test can be reduced.

As mentioned above, in order to have better EMC characteristics and heat dissipation performance, the switching devices S3 and S4 in the full bridge module are placed in an insulating layer (ie, the insulating layer of the thermally conductive insulating material layer) Above, the switching devices S1, S2 are directly placed on the heat dissipating unit 11; in order to facilitate production and reduce space waste caused by production work, the switching devices S3, S4 are placed on the connected insulating layer; Inductive and easy to use, place S2 on the outside of S3 and place S1 on the outside of S4. That is to say, for the full-bridge circuit shown in FIG. 2, the internal components of the module are arranged in the order of S2-S3-S4-S1 or S1-S4-S3-S2, and the performance is more excellent.

In addition, in the above embodiments, the power converter may include at least two of the power modules, and the two power modules may be sealed by the same sealing mold to reduce the cost of the sealing mold.

In addition, the lead frame can also be integrated with a heat sink unit, and this heat sink unit can also be used as a carrier for mounting components. The heat dissipating unit referred to herein is defined as a portion where the connecting body is covered by the encapsulating material.

The manufacturing process of the power module of the present embodiment is described below. Here, the thermal conductive insulating material layer is exemplified by a copper-clad ceramic substrate. In addition, the power module integrates some passive components in addition to the power device (semiconductor wafer). For example, resistors and capacitors, and a temperature measuring resistor on some of the leads of the lead frame is used for module over temperature protection. The specific manufacturing process is as follows: first, the position of the heat conductive insulating material layer 13 is assembled on the heat radiating unit 11 and the solder paste is applied to the position where the lead frame 15 is connected, and the position of the heat conductive insulating material layer 13 to be assembled with the lead frame 15 is also applied. After soldering, the heat dissipating unit 11, the heat conductive insulating material layer 13 and the lead frame 15 are placed in a fixture according to a set assembly relationship; and then soldered together by a reflow furnace (Reflow). The three components are formed in one piece, and the lead frame 15 can be used for transmission and positioning in the subsequent crystallization process; after cleaning (Flux Cleaning), the semiconductor devices (such as transistors and diodes) required for the lithographic mounting are performed. It is important to emphasize here that some power devices are placed in the heat dissipation unit 11 On top (such as the first power device 12), another portion of the power chip is placed on the thermally conductive insulating material layer 13 (such as the second power device 14); when using a single function crystallizer, since it does not have a gripping surface adhesion ( SMT) device capabilities, therefore, some resistors, capacitors and other devices also need to perform SMT operation, namely: after the solder paste (Solder Dispense), placed other components (SMT); due to the power device used in the larger chip size When reflow is performed with a solder paste, there is a problem that the porosity of the solder layer is high, resulting in poor processability and reliability. Here, vacuum reflow is used to make the component and the heat dissipation unit 11, and heat conduction. The insulating material layer 13 and the lead frame 15 are welded together; after cleaning (Flux Cleaning), wire bonding work is performed; after the Molding, the main process is completed.

In some applications where the lead frame 15 is not required for positioning during the lithography process, there is an opportunity to further simplify the process. First, the solder paste is applied to the required positions on the heat dissipating unit 11, the thermally conductive insulating material layer 13, and the lead frame 15. The required components (power chips and passive SMT components) are then placed in the desired positions, respectively. It can be realized in one-stop operation with a strong machine (such as a machine with integrated crystallization and surface adhesion technology), and can also be realized on multiple machines; then the heat-dissipating unit 11 with components and thermal conductive material will be placed. The layer 13 and the lead frame 15 are placed in a jig according to a set assembly relationship to complete the assembly; then vacuum reflow; the subsequent process is the same as the above process. In this way, the number of reflows and the corresponding cleaning processes can be reduced, and the reduction in the number of reflows has certain advantages for improving the reliability of the module.

In summary, the packaging method and structure for improving the power density or efficiency of the power converter disclosed by the present invention can obtain better thermal performance, electrical performance, economic performance, EMC performance and more than the prior art. High reliability. Its internal space The utilization rate is high and the use is convenient, which is very beneficial to improve the power density or efficiency of the converter. The specific implementation of the specific power module given by the present invention is also very feasible and effective. The invention is well suited for improving the overall performance and cost performance of a power converter.

The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims.

10‧‧‧Power Module

11‧‧‧First heat sink unit

111‧‧‧First District

112‧‧‧Second District

12‧‧‧First power device

13‧‧‧ Thermally Conductive Insulation Layer

131‧‧‧thermal layer

132‧‧‧Insulation

133‧‧‧Line layer

14‧‧‧second power device

15‧‧‧ lead frame

16‧‧‧Filling

17‧‧‧bonding material layer

A1‧‧‧ front surface

A2‧‧‧ rear surface

D‧‧‧thickness

Claims (40)

A power module includes: a first power device and a second power device, each of the power devices being encapsulated in the same sealing material, each of the power devices having at least two electrodes, at least one of the power devices having at least three The electrode, at least one of the power devices operating at a frequency above 25 kHz, wherein the power module is applied to a power converter, wherein at least one power device internal to the power converter has an operating voltage higher than 48 volts, the power conversion The power density and maximum efficiency of the device are greater than 15w/inch3 and higher than 92%, respectively, or the power density of the power converter is greater than 20w/inch3, or the highest efficiency of the power converter is higher than 93%, the power module accounts for The total volume ratio of the power converter is less than 50%, and the power conversion stage processing power of the power module accounts for at least 30% of the total output power of the power converter, and the total output power of the power converter is above 150W. The power module of claim 1, wherein the power converter is an isolated AC/DC power converter, or a non-isolated AC/DC power converter, or an isolated DC/DC converter, Or a DC/AC converter, the power converter and the highest efficiency of the power converter are respectively greater than 20w/inch3 and higher than 93%, or the power converter has a power density greater than 25w/inch3, or the highest efficiency of the power converter is high. At 94%. The power module of claim 1, wherein when the power module is mounted on a surface of a circuit board, the highest point of the power module is 35 mm from the surface of the circuit board. Hereinafter, the total thickness of the power module is less than 6 mm. The power module of claim 3, wherein the power module is the highest The height of the surface from the board is 21 mm or more. The power module of claim 3, wherein the power module has a pin extending from the lower side of the power module and standing on the circuit board. The power module of claim 4, having a front surface and a rear surface, wherein the front surface and the rear surface are at least 80% or more in a 5 m/s balanced wind speed parallel wind cooling environment. Within, the maximum temperature difference at each point is less than 20% of the average temperature rise of the front surface and the back surface relative to the working environment. The power module of claim 5, wherein the power module is applied to a power converter, the power density and the highest efficiency of the power converter are greater than 25 w/inch 3 and higher than 95%, respectively. The power converter has a power density greater than 30 w/inch 3 or the highest efficiency of the power converter is greater than 96%. For example, in the power module of claim 7, the operating voltage of at least one power device inside the power converter applied is higher than 200 volts. The power module of claim 5, wherein the width of the power module is less than 60 mm, wherein the pin pitch is between 3 mm and 5 mm at an operating voltage of 400 V, and the pin pitch is at an operating voltage of 30 V. The system is between 0.5mm and 2mm. The power module of claim 1, further comprising: a first heat dissipating unit, the first power device and the second power device are disposed above the first heat dissipating unit; a lead frame, and the At least one of the first power device and the second power device is electrically connected; and a material covering the first power device, the second power device, and a portion of the lead frame. The power module of claim 10, wherein the first heat dissipation unit has a first area and a second area, and the first power device is disposed in the first area, the work The rate module further includes: a layer of thermally conductive insulating material disposed in the second region and having an insulating layer, wherein the second power device is disposed on the first heat dissipating unit by the layer of thermally conductive insulating material; wherein the sealing material is further included Covering a portion of the layer of thermally conductive insulating material; and the first heat dissipating unit is electrically connected to at least one of the first power device and the second power device. The power module of claim 10, wherein the first heat dissipation unit is integrally formed with the lead frame. The power module of claim 10, wherein the first heat dissipating unit is completely disposed in the sealing material, or part of the material is outside the sealing material, or is completely outside the sealing material. The power module of claim 10, wherein the first heat dissipating unit is connected to a pin that passes through the sealing material, or the first heat dissipating unit passes through the sealing material and forms a pin. . The power module of claim 14, wherein the first heat dissipation unit is electrically connected to a voltage static location. The power module of claim 10, wherein the first heat dissipating unit is divided into a plurality of parts. The power module of claim 11, wherein the thermally conductive insulating material layer further has a circuit layer, and the lead frame extends to be coupled to the circuit layer. The power module of claim 10, wherein the lead frame extends to be coupled to at least one of the first power device and the second power device. The power module of claim 11, further comprising: a second heat dissipating unit disposed between the second power device and the layer of thermally conductive insulating material. For example, the power module described in claim 10 of the patent scope further includes: A third heat dissipating unit is disposed on the first heat dissipating unit or extended by the first heat dissipating unit. The power module of claim 20, wherein the third heat dissipating unit passes through the sealing material. The power module of claim 21, wherein the third heat dissipating unit passes through the sealing material and has a bend. The power module of claim 21, further comprising: a fourth heat dissipating unit coupled to the third heat dissipating unit and having a gap with the sealing material. The power module of claim 11, wherein the thermally conductive insulating material layer is a metal substrate or a metallized ceramic substrate. The power module of claim 11, further comprising: a bonding material layer, wherein the first power device is connected to the first heat dissipating unit by the bonding material layer, the material of the bonding material layer The thermal conductivity is greater than or equal to 2W/mK. The power module of claim 10, further comprising a row of pins that pass through the sealing material and transmit or dissipate as a signal. The power module of claim 26, wherein the total heat dissipation of the row of pins is greater than or equal to 5% of the total heat dissipation of the power module. The power module of claim 11, further comprising: a control device disposed in the first zone. The power module of claim 28, further comprising: a heat insulating layer disposed between the control device and the first heat dissipation unit. The power module of claim 1, further comprising: a high frequency capacitor integrated in the power module. For example, the power module described in claim 1 of the patent scope further includes: A temperature sensor is integrated in the power module. The power module of claim 10, wherein the thickness of the first heat dissipation unit is greater than 20% of the thickness of the power module. The power module of claim 32, wherein the first heat dissipation unit has a thickness of less than 3 mm. The power module of claim 10, wherein the distance between the sealing material and the first power device or the second power device is less than 60% of the thickness of the power module, and less than 3 mm. The power module of claim 11, wherein the thermal conductive material layer has an upper and lower thermal resistance system of less than 3 K/W in a 10×10 area. The power module of claim 1, further comprising: a third power device disposed on the second power device; a fourth power device disposed on the first power device; a lead frame between the first power device and the fourth power device, and between the second power device and the third power device, and located above the third power device and the fourth power device; And a material covering the power devices and at least a portion of the lead frame. The power module of claim 1, wherein the power converter comprises at least two of the power modules. The power module of claim 37, wherein the two power modules are sealed by the same sealing mold. The power module of claim 10, wherein the sealing material has a thermal conductivity higher than 1.2 W/m.K. The power module of claim 10, wherein the sealing material has a thermal conductivity higher than 1.8 W/m.K.