KR20110004514A

KR20110004514A - Power module assembly

Info

Publication number: KR20110004514A
Application number: KR1020090061967A
Authority: KR
Inventors: 김형일
Original assignee: 주식회사 리홈
Priority date: 2009-07-08
Filing date: 2009-07-08
Publication date: 2011-01-14

Abstract

The present invention is a power module that can reduce the material cost and improve the production efficiency by shortening the manufacturing process by excluding the configuration of the aluminum PCB layer used to dissipate the heat of the elements in the module and constituting the thermal conductive sheet as an insulating layer Start the structure. The configuration of the present invention comprises a lead frame; An element unit including a plurality of circuit elements; A power device electrically connected to the lead frame; A double-sided PCB core on which the device unit and the power device are mounted; A sealing layer protecting the device portion and the power device mounted on the lower portion of the PCB core; An insulation layer formed on an upper surface of the PCB core; And a heat sink bonded to the insulating layer to dissipate heat generated in the device unit and the power device to the outside.

Description

Power Module Assembly

The present invention relates to a power module structure, and more particularly, by excluding the configuration of the aluminum PCB used to dissipate the heat of the elements in the module, and by configuring a thermally conductive sheet with an insulating layer to reduce the material cost and shorten the manufacturing process Due to the power module structure that can improve the production efficiency.

In general, a semiconductor package is mounted on a lead frame or a printed circuit board and sealed with a sealing material such as an epoxy molding compound (EMC) to protect the interior, and then to the motherboard or system It is used by mounting on PCB Core (Printed Circuit Board CORE).

Recently, as high-speed, high-capacity and high-integration of electronic devices has progressed, the demand for miniaturization and light weight of power devices has also increased. One way to solve the above requirement is to configure a stacked power module by mounting a plurality of semiconductor chips in a single semiconductor package.

1 is an exemplary view showing an example of a conventional power module structure.

The semiconductor chip package 910 illustrated in FIG. 1 is a multi-chip package including a plurality of semiconductor chips 911 and 913 having bonding pads 912 and 914 formed at chip edges, and the plurality of semiconductor chips 911 and 913 are substrates 921. It is a structure laminated vertically on).

The semiconductor chips 911 and 913 and the substrate 921 are electrically connected by wire bonding, and the first semiconductor is positioned below by a spacer 917 interposed between the semiconductor chips 911 and 913. The height of the wire loop of the bonding wire 931 connecting the chip 911 is secured.

The semiconductor chips 911 and 913, the bonding wire 931, and the junction portions thereof are covered by an encapsulant 961 formed of an epoxy molding resin (EMC) to cover the upper portion of the substrate 921, thereby protecting the external environment. The solder ball 971 formed on the lower surface of the substrate 921 is used as an external connection terminal for electrical connection with the outside.

However, in the case of the conventional semiconductor chip package including a plurality of chips as described above, the amount of heat generated according to the operation is increased, which causes various problems due to thermal stress.

In addition, in the case of a multi-chip package in which a plurality of chips are stacked through spacers, a heat trapping phenomenon, which is accumulated without heat dissipation, occurs between the chips and the chip. The effect of heat transfer to the system becomes less severe, causing problems due to thermal stress.

In particular, since the heat generation increases due to the increased junction temperature of the chip internal circuit due to the high speed operation and the high integration, the electronic devices using the semiconductor chip package, for example, mobile products, do not smoothly discharge heat corresponding to the increased heat generation. Characteristics of the conductor chip package, for example, refresh characteristics, operating speed, lifespan, etc. may be deteriorated.

Looking at the power module structure disclosed to reduce such thermal stress is as follows. 2 is an exemplary view showing another conventional power module structure, Figure 3 is an exemplary view showing another conventional power module structure.

In another example of the conventional power module structure as shown in FIG. 2, the insulating layer 20 is formed on the lower portion of the substrate 10 made of aluminum, and the power element 30, the wire 35, and the element chip 40 are formed on the lower surface thereof. ) And the lead frame 50 are mounted and covered with a sealing material 90 to protect the elements. In addition, the substrate 10 is mounted with a heat sink 60 for radiating heat generated from the module to the outside.

Meanwhile, as shown in FIG. 3, the copper foil 25 was formed below the substrate 10 and the insulating layer 20 was formed on the top and bottom surfaces of the layer made of the copper foil 25 to form a multilayer substrate. .

However, these power module structures have a structure in which a circuit board is formed by adhering the insulating layer 20 to a substrate 10 made of aluminum and forming a pattern on the copper foil 25 thereon.

Accordingly, the conventional power module structure is provided with a separate aluminum substrate 10 to transfer heat emitted from the device to the heat sink 60, which acts as a factor of increasing the material cost, and produced by the addition of the manufacturing process There was a problem that the efficiency is lowered.

The present invention was created by the above needs, by excluding the configuration of the aluminum PCB layer used to dissipate heat of the device in the module and by configuring the thermally conductive sheet as an insulating layer to reduce the material cost and shorten the manufacturing process The purpose is to provide a power module structure that can improve the production efficiency.

According to an embodiment of the present invention for achieving the above object, a lead frame (lead frame); An element unit including a plurality of circuit elements; A power device electrically connected to the lead frame; A double-sided PCB core on which the device unit and the power device are mounted; A sealing layer protecting the device portion and the power device mounted on the lower portion of the PCB core; An insulation layer formed on an upper surface of the PCB core; And a heat dissipation plate bonded to the insulating layer to dissipate heat generated by the device unit and the power device to the outside.

Preferably, the double-sided PCB core has a plurality of thermally conductive parts formed to correspond to the devices mounted on the lower surface.

Preferably, the thermally conductive portion is formed at a position corresponding to the power device.

According to the present invention, by excluding the configuration of the aluminum PCB layer used to dissipate heat of the device in the module, it is possible to reduce the material cost and improve the production efficiency due to the shortening of the manufacturing process.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 is an exemplary view showing a power module structure according to an embodiment of the present invention.

As shown in FIG. 4, the power module structure of the present invention includes a lead frame 50, an element unit 40, a power element 30, a double-sided PCB core 80, a sealing layer 90, and an insulating layer 20. ), And the heat sink 60.

The heat sink 60 has a plurality of heat radiation fins are formed to perform the function of dissipating heat transferred from the substrate to the outside, usually made of aluminum or other metal material.

The insulating layer 20 is bonded to the lower surface of the heat sink 60, but the insulating layer 20 is preferably made of a material having high thermal conductivity and high insulating property.

The double-sided PCB core 80 may be a FR4 that can implement a PCB on both sides of the epoxy material, wherein the copper foil sheet 25 may be bonded to both sides of the double-sided PCB core 80.

The device unit 40 is equipped with a variety of device chips, it is mounted on the lower side of the double-sided PCB core (80). Here, reference numeral 27 denotes a solder paste.

The power device 30 is also mounted on the lower surface of the double-sided PCB core 80. The device unit 40 or the power device 30 is bonded to the wire 35 by the lead frame 50. It is mounted on

Meanwhile, a plurality of heat conductive parts 85 may be formed on the double-sided PCB core 80 so as to correspond to devices (particularly, power devices) 30 mounted on a lower surface thereof. The heat conductive portion 85 is a means for connecting the power element 30 having a high heat generation and the insulating layer 20 formed on the lower surface of the heat sink 60. Accordingly, the heat generated by the power device 30 is transferred to the insulating layer 20, and the transferred heat is transmitted to the heat sink 60 to dissipate to the outside air.

The sealing layer 90 is formed of an epoxy resin and serves to protect the device unit 40 and the power device 30 with an external shock.

In the present invention having such a configuration, the copper foil sheet 25 is bonded to the double-sided PCB core 80 of FR4, which is capable of circuit configuration on both sides, thereby maintaining heat transfer characteristics without forming a separate aluminum PCB on the substrate.

In addition, since the insulating layer 20 is composed of a thin film of 0.1mm or less, the thermal resistance between the module and the heat sink 60 is reduced, and high temperature compression is easily performed during manufacturing, thereby increasing the ease of manufacturing operation.

In addition, since the insulating layer 20 is formed of a ceramic material, the circuit pattern is not exposed to the outside, thereby protecting the module circuit from external shock.

While the present invention has been particularly shown and described with reference to the particular embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

2 is an exemplary view showing another conventional power module structure.

3 is an exemplary view showing another conventional power module structure.

10: substrate 20: insulating layer

30: power element 35: wire

40: device chip 50: lead frame

60: heat sink 90: sealing material

Claims

Lead frames;

An element unit including a plurality of circuit elements;

A power device electrically connected to the lead frame;

A double-sided PCB core on which the device unit and the power device are mounted;

A sealing layer protecting the device portion and the power device mounted on the lower portion of the PCB core;

An insulation layer formed on an upper surface of the PCB core; And

And a heat sink bonded to the insulating layer to dissipate heat generated from the device portion and the power device to the outside.

The method according to claim 1,

The double-sided PCB core is a power module structure, characterized in that a plurality of heat conductive parts formed to correspond to the device mounted on the lower surface.

The method according to claim 2,

And the heat conducting portion is formed at a position corresponding to the power element.