This application claims the priority benefit of Taiwan application serial no. 108128918, filed on Aug. 14, 2019. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
The disclosure relates to a package structure, and particularly, to a package structure for power devices.
At present, a power module is a main core apparatus for electric energy conversion in various products, inside which power devices are packaged. At early stage, an aluminum (Al) metal wire is used as a connection line between chips in the power module, and the excessive parasitic inductance and parasitic impedance cause high electric power conversion loss and uneven current distribution.
The invention provides a package structure for power devices, which can solve the problem of electric power conversion loss caused by the excessive parasitic effect of the traditional power module.
The invention further provides a package structure for power devices, which can reduce the stray inductance and thermal resistance of the power module.
The package structure for power devices of the invention includes a heat dissipation insulating substrate, a plurality of power devices, at least one conductive clip and a heat dissipation baseplate. The heat dissipation insulating substrate has a first surface and a second surface opposite thereto. The power devices form a bridge circuit topology and are disposed on the first surface, wherein active regions of at least one of the power devices are flip-chip bonded to the first surface. The conductive clip is configured to electrically connect at least one of the power devices to the first surface. The heat dissipation baseplate is disposed at the second surface of the heat dissipation insulating substrate.
In an embodiment of the invention, one conductive clip electrically connects one or more of the power devices to the heat dissipation insulating substrate and is disposed at an opposite side of the power device opposite to a side where the power device is bonded to the heat dissipation insulating substrate.
In an embodiment of the invention, a material of the conductive clip includes aluminium, copper or graphite.
In an embodiment of the invention, the plurality of power devices include, for example, vertical power devices, active regions of the vertical power devices are flip-chip bonded to the first surface, and the at least one conductive clip electrically connects non-active regions of the vertical power devices to the first surface.
In an embodiment of the invention, the heat dissipation insulating substrate includes a direct bonded copper (DBC) ceramic substrate, a direct plating copper (DPC) ceramic substrate, an insulating metal substrate (IMS) or a printed circuit board (PCB).
In an embodiment of the invention, the heat dissipation insulating substrate has a patterned circuit which contains a plurality of electrical functions and is electrically connected with the at least one conductive clip, and the patterned circuit is electrically connected with the plurality of power devices.
In an embodiment of the invention, one conductive clip may connect the patterned circuit of different electrical functions.
In an embodiment of the invention, the second surface of the heat dissipation insulating substrate is monolithically formed with the heat dissipation baseplate or thermally contacts with the heat dissipation baseplate.
Another package structure for power devices of the invention includes: a heat dissipation insulating substrate, a plurality of vertical power devices and at least one conductive clip. The plurality of vertical power devices form a bridge circuit topology, and active regions of at least one of the vertical power devices are flip-chip bonded to the heat dissipation insulating substrate. The conductive clip electrically connects non-active regions of the vertical power devices, which are flip-chip bonded to the heat dissipation insulating substrate, to the heat dissipation insulating substrate.
In another embodiment of the invention, the heat dissipation insulating substrate has a patterned circuit which contains a plurality of electrical functions and is electrically connected with the at least one conductive clip, and the patterned circuit is electrically connected with the plurality of vertical power devices.
In another embodiment of the invention, one conductive clip connects the patterned circuit of different electrical functions.
In another embodiment of the invention, the package structure for power devices further includes a heat dissipation baseplate disposed at another surface of the heat dissipation insulating substrate other than a surface where the heat dissipation insulating substrate is bonded to the plurality of vertical power devices.
In another embodiment of the invention, the heat dissipation insulating substrate is monolithically formed with the heat dissipation baseplate or thermally contacts with the heat dissipation baseplate.
Based on the above, the package structure for power devices of the invention is a connection configuration where the power device is directly flip-chip bonded to the heat dissipation substrate, and the conductive clip is used to replace the aluminium metal line as a circuit, which achieves the effects of reducing the stray inductance and thermal resistance of the power module by virtue of low parasitic impedance and parasitic inductance of the heat dissipation substrate and the conductive clip, so as to reduce the electrical power conversion loss and more evenly distribute the current.
In order to make the aforementioned and other objectives and advantages of the invention comprehensible, embodiments accompanied with figures are described in detail below.
Many different implementations or examples are provided by the following disclosed content to implement different features of the invention. Certainly, these embodiments are only examples and are not intended to limit the scope and application of the invention. In addition, the relative thicknesses and positions of components, films, or regions may be reduced or enlarged for clarity. In addition, same or like reference numerals are used in the accompanying drawings to indicate same or like elements or features. Details of reference numerals that appear in one drawing may be omitted in the description of the following drawings.
Referring to
In the first embodiment, the conductive clip 106 is configured to electrically connect at least one of the power devices 104 with the first surface 102a, wherein the material of the conductive clip 106 is, for example, aluminium, copper or graphite. Furthermore, one conductive clip 106 may electrically connect a plurality of power devices 104 to the heat dissipation insulating substrate 102 and is disposed at an opposite side 104b of the power device 104 opposite to a side where the power device 104 is bonded to the heat dissipation insulating substrate 102. However, the invention is not limited thereto, one conductive clip 106 may also only electrically connect one power device 104 to the heat dissipation insulating substrate 102. In one embodiment, if the power device 104 is a vertical power device, a part of the conductive clip 106 may electrically connect the non-active regions of the vertical power devices, and the other part of the conductive clip 106 may electrically connect the first surface 102a. In addition, mutual electric connection may be formed between the first surface 102a and the conductive clip 106 by virtue of a first conductive connection layer 110, and mutual electric connection may be formed between the power device 104 and the conductive clip 106 by virtue of a second conductive connection layer 112, but the invention is not limited thereto. The first conductive connection layer 110 and the second conductive connection layer 112 are, for example, sintered silver layers or other conductive connection layers.
Referring again to
The heat dissipation baseplate 108 is disposed at the second surface 102b of the heat dissipation insulating substrate 102, and may be mutually electrically connected via a third conducive connection layer 122, wherein the third conductive connection layer 122 is, for example, a sintered silver layer or other conductive connection layers. However, the invention is not limited thereto.
The second surface 102b of the heat dissipation insulating substrate 102 may also be monolithically formed with a heat dissipation baseplate 200 or thermally contact with the heat dissipation baseplate 200, as shown in
Referring to
Referring to
In
The above circuits are only one embodiment of the package structure for power devices of the invention and are not intended to limit the application scope of the invention.
If the half-bridge circuit of
In addition, because the area and thermal conductivity coefficient of the conductive clip (such as a copper clip) are both higher than those of traditional aluminium metal wires for wire bonding, the thermal resistance (RJF) can be reduced from 0.14° C./W in the case of the traditional wiring to 0.10° C./W in the case of using the conductive clip, wherein the thermal resistance drop is as much as 30%.
Based on the above, according to the invention, the power devices are directly bonded to the heat dissipation insulating substrate through the flip-chip bonding technology, and the conductive clip is used as the connection configuration of the circuit. Therefore, by virtue of the properties of the heat dissipation insulating substrate and the conductive clip, such as low parasitic impedance and low parasitic inductance, the stray inductance and the thermal resistance of the power module can be reduced, which further reduces the electric power conversion loss, more evenly distributes the current, and decreases the voltage surge.
Although the invention is described with reference to the above embodiments, the embodiments are not intended to limit the invention. A person of ordinary skill in the art may make variations and modifications without departing from the spirit and scope of the invention. Therefore, the protection scope of the invention should be subject to the appended claims.
Number | Date | Country | Kind |
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108128918 | Aug 2019 | TW | national |