KR20060029720A - Semiconductor device combined bimetal clip - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device having a bimetallic clip coupled thereto. Provided is a semiconductor device having a bimetal clip coupled to a bimetal clip on both sides thereof. In other words, by bonding the bimetal clips to the upper and lower surfaces of the laminated package or module, the electrical connection portion is pressed at a predetermined pressure in the solder reflow process for electrical connection between the stacked semiconductor packages or between the semiconductor package and the substrate. In addition, it is possible to prevent defects in the semiconductor packages as well as securing good solder bonding properties.

The bimetal clip may be a metal to improve heat dissipation characteristics of the semiconductor device, and an adhesive may be interposed between the semiconductor element and the bimetal clip to further improve the heat dissipation characteristics. Alternatively, in order to reduce mechanical stress applied to the semiconductor device, portions of the both surfaces of the semiconductor device that are pressed may be formed in the form of an uneven plate. Alternatively, in the case of a module in which several semiconductor packages are mounted on a module substrate, bimetal clips may be independently attached to the semiconductor packages. Of course, when the semiconductor package is mounted on both sides of the module substrate, the bimetallic clips are coupled in pairs of semiconductor packages positioned up and down with the module substrate therebetween.

Bimetal, clip, clamp, laminated, module

Description

Semiconductor device combined bimetal clip

1 and 2 are views illustrating a laminated package in which a bimetallic clip is coupled according to a first embodiment of the present invention.

3 is a view showing a cross-sectional module coupled to a bimetal clip according to a second embodiment of the present invention.

4 is a view illustrating a double-sided module to which a bimetal clip is coupled according to a third embodiment of the present invention.

5 is a view illustrating a double-sided module to which a bimetal clip is coupled according to a fourth embodiment of the present invention.

6 is a view illustrating a double-sided module to which a wave type bimetal clip is coupled according to a fifth embodiment of the present invention.

7 is a plan view illustrating a module to which a U-shaped bimetallic clip according to a sixth exemplary embodiment of the present invention is coupled.

Description of the main parts of the drawing

10: laminated package 11, 12: semiconductor package

13: solder ball 17: crimp plate                 

18: connecting plate 19: bimetallic clip

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly, a bimetallic clip is provided to ensure good solder bonding when stacking a semiconductor package or mounting a semiconductor package on a substrate, and to suppress warpage of the semiconductor device due to repeated reflow. It relates to a combined semiconductor device.

With the trend toward thinner and shorter electronic devices, high-density and high-mounted packages are becoming important factors, and in the case of computers, large amounts of random access memory (RAM) and flash memory are increasing with increasing storage capacity. Like the Flash Memory, the size of the chip grows naturally, but the package is being studied to be smaller in accordance with the above requirements.

Here, various methods that have been proposed to reduce the size of a package include, for example, a chip scale package (CSP) close to the chip size, a stack package in which a plurality of semiconductor packages are stacked, and at least one surface of a wiring board. And a semiconductor module in which a plurality of semiconductor packages or stacked packages are planarly mounted.

Such a semiconductor device is bonded to a printed circuit board through solder reflow. As the thickness of the semiconductor device becomes thinner, a defect in bending of the semiconductor device occurs due to the heat applied during the solder reflow process. The problem of inferior solder bonding may occur at the portion.

In the multilayer package, when a plurality of semiconductor packages are stacked in three dimensions, a solder reflow process is performed for electrical connection between the semiconductor packages, and a solder reflow process is performed again to mount the multilayer package on a printed circuit board. As a result, the solder bondability between the semiconductor packages due to the remelting of the solder may be inferior, or a defect in the bending of the semiconductor packages may occur.

The same problem may occur when implementing a semiconductor module. That is, the solder bonding of the semiconductor packages to the module substrate may be inferior, or the bending of the semiconductor packages mounted on the module substrate may occur. In particular, when the semiconductor package mounted on the module substrate is a laminated package, the frequency of occurrence thereof may increase.

Accordingly, it is an object of the present invention to ensure good solder bonding when laminating semiconductor packages or mounting semiconductor devices on a substrate.

Another object of the present invention is to be able to suppress the failure of the semiconductor element or substrate when the semiconductor element is mounted on the substrate.

In order to achieve the above object, the present invention provides a semiconductor device in which a bimetallic clip capable of adjusting the clamping strength according to the reflow temperature is coupled to both surfaces of the semiconductor device.

In a preferred embodiment according to the present invention, in a semiconductor device in which at least one semiconductor package is stacked, the semiconductor device further comprises a bimetallic clip fitted to and coupled to the uppermost and lowermost semiconductor package, wherein the bimetallic clips are installed in parallel with each other, and the uppermost and A compression plate contacting and pressing the lowermost semiconductor package, respectively; It provides a semiconductor device coupled to the bimetal clip comprising a; connecting plate for connecting both ends of the crimping plate.

The connection between the semiconductor packages according to the present invention is made by solder balls, and the solder balls formed on the lower surface of the lowermost semiconductor package are formed in a region spaced apart from the pressing plate.

The semiconductor device according to the present invention may further include an adhesive interposed between the uppermost and lowermost semiconductor packages and the pressing plate.

The present invention also provides a module substrate; At least one semiconductor package mounted on at least one surface of the module substrate; And a bimetallic clip inserted into and coupled to both surfaces of the module substrate, wherein the bimetallic clip includes: a pressing plate which is installed in parallel with each other and is pressed against the both sides of the module substrate; It provides a semiconductor device coupled to the bimetal clip comprising a; connecting plate for connecting both ends of the crimping plate.

In the semiconductor device according to the present invention, at least one semiconductor package is mounted on one surface of a module substrate, and a bimetal clip is coupled to a surface opposite to the upper surface of the semiconductor packages and one surface of the module substrate.

In the semiconductor device according to the present invention, at least one semiconductor package is mounted on both surfaces of a module substrate, and a bimetal clip is coupled to upper surfaces of semiconductor packages on both sides of the module substrate.

In the bimetallic clip according to the present invention, the compressed plate bonded to the semiconductor packages in the form of “⊃” may be formed of an uneven plate.

In addition, the bimetallic clip according to the present invention is independently coupled to each semiconductor package mounted on the module substrate, and the pressing plate coupled to the semiconductor package has a “U” shape.

Hereinafter, with reference to the accompanying drawings will be described in detail an embodiment of the present invention.

1 and 2 show a stack package 10 to which a bimetallic clip 19 is coupled according to a first embodiment of the present invention.

1 and 2, in the multilayer package 10 to which the bimetallic clip 19 is coupled, semiconductor packages 11 and 12 having solder balls 13 formed on a lower surface thereof are stacked. The structure has a structure in which the bimetallic clip 19 is coupled to the top and bottom semiconductor packages 11 and 12.

At this time, since the solder balls 13 of the lowermost semiconductor package 12 are formed at both edges of the lower surface of the lowermost semiconductor package 12, the bimetallic clip 19 is fitted into the space between the solder balls 13 to be joined. do.

The bimetallic clip 19 includes a crimping plate 17 installed in parallel with each other, and a connecting plate 18 connecting both ends of the crimping plate 17 and has a cross-section "⊃". And the bimetal clip 19 can adjust the deformation of the bimetallic clip 19 according to the reflow temperature according to the adoption of the metal material disposed on both sides, so in the case of increasing the pressing pressure at a high temperature, the bimetallic clip 19 In the case where a metal having a large thermal expansion coefficient is used on the outside of (19) and a pressure to be pressed at a high temperature is lowered, a semiconductor package laminated at the time of reflow by using a metal having a large thermal expansion coefficient on the inside of the bimetallic clip 19 ( It is easy to control the pressure that can act on 10).

Therefore, since the bimetallic clip 19 is pressed at a predetermined pressure in the reflow process for the electrical connection of the stacked semiconductor packages 11 and 12, the semiconductor packages 11 and 12 are secured together with ensuring a good solder bonding property. Warping defect can be suppressed.

In addition, since the bimetallic clip 19 may play a role of a heat sink as a metal material, a heat dissipation effect may also be expected after manufacturing the laminated package 10. At this time, in order to enhance the heat dissipation effect, the bimetallic clip 19 may be provided between the uppermost and lowermost semiconductor packages 11 and 12 and the pressing plate 17 of the bimetallic clip.

In addition, in order to further increase the heat dissipation effect, a separate heat sink may be further attached to the upper surface of the compression plate 17 installed in the uppermost semiconductor package 11.

In the first embodiment, a structure in which the bimetallic clip 19 is coupled to the laminated package 10 is disclosed. However, as shown in FIGS. 3 to 5, the bimetallic clip according to an embodiment of the present invention is applied to a single-sided or double-sided module. You can also combine.

Referring to FIG. 3, the semiconductor device according to the second embodiment is a cross-sectional module 20, in which a semiconductor package 22 is mounted on an upper surface of a module substrate 21, and a bimetallic clip 29 is a semiconductor package. It has a structure coupled to the upper surface of the 22 and the lower surface of the module substrate 21.

As described above, the bimetallic clip 29 may be used as a heat sink, and the bimetallic clip 29 may be coupled to the cross-sectional module 20 through an adhesive to increase the heat dissipation effect.

In addition, in order to further increase the heat dissipation effect, a separate heat sink may be further attached to the upper surface of the compression plate 27 installed in the semiconductor package 22.

Referring to FIG. 4, the semiconductor device according to the third embodiment is a double-sided module 30, in which semiconductor packages 32 and 33 are mounted on both sides of the module substrate 31, and the bimetallic clip 39 is a module. It has a structure coupled to the outer surface of the semiconductor package (32, 33) mounted on both surfaces of the substrate 31.

Referring to FIG. 5, the semiconductor device according to the fourth embodiment is a double-sided module 40, in which the stack packages 42 and 43 are mounted on both sides of the module substrate 41, and the bimetallic clip 49 is a module. It has a structure coupled to the outer surface of the laminated package (42, 43) mounted on both sides of the substrate 41.

On the other hand, the bimetallic clip applied to the semiconductor device according to the first to fourth embodiments has a cross section “⊃” so that the pressing plate compresses the entire surface of the outer surface of the semiconductor package, and the thickness of the semiconductor package is thin or the outside of the semiconductor package. When the exposed semiconductor chip is pressed, mechanical stress may occur due to the pressing.                     

Therefore, in order to minimize the mechanical stress caused by the compression of the bimetallic clip, as shown in FIG. 6, the pressing plate 57 of the bimetallic clip 59 may be formed in an uneven plate shape. The semiconductor device according to the fifth embodiment is a double-sided module, in which semiconductor packages 52 and 53 are mounted on both sides of a module substrate, and a bimetallic clip 59 is mounted on both sides of a module substrate 51. 52, 53, has a structure coupled to the outer surface. At this time, by forming the pressing plate 57 of the bimetallic clip in the form of an uneven plate, it is possible to reduce the mechanical stress acting on the semiconductor packages 52 and 53 by reducing the contact area with the semiconductor packages 52 and 53.

In addition, in the modules according to the second to fifth embodiments, a structure in which a bimetallic clip is combined to form a crimp of the semiconductor packages mounted on the module substrate as a whole has been disclosed. The semiconductor module 60 according to the example has a structure in which a plurality of semiconductor packages 62 are mounted on a module substrate 61, and a bimetal clip 69 is independently coupled to each semiconductor package 62. At this time, the pressing plate 67 of the bimetallic clip in close contact with the outer surface of the semiconductor package 62 may be implemented in the English letter "U" form. As described above, the bimetal clip 69 having the pressing plate 67 of the letter “U” is preferably used for pressing the semiconductor package 62 in which solder balls (not shown) are formed around the edge of the lower surface.

Of course, the pressing plate 67 of the bimetallic clip according to the sixth embodiment may be formed in the form of an uneven plate as disclosed in the fifth embodiment.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are merely presented specific examples to aid understanding, and are not intended to limit the scope of the present invention. In addition to the embodiments disclosed herein, it is apparent to those skilled in the art that other modifications based on the technical idea of the present invention may be implemented.

Therefore, according to the structure of the present invention, by bonding the bimetal material clip to the upper and lower surfaces of the laminated package or module, the clip is electrically connected at a predetermined pressure in the reflow process for the electrical connection between the stacked semiconductor packages or between the semiconductor package and the substrate. By pressing the connection portion, it is possible to secure a good solder joint and to suppress the bending of the semiconductor package.

That is, since the bimetallic clip is coupled to both surfaces of the semiconductor element and exerts a predetermined pressing force as a whole, the warpage of the semiconductor package or substrate in the semiconductor element can be suppressed.

In addition, the bimetallic clip can control the deformation of the bimetallic clip according to the reflow temperature according to the adoption of a metal material disposed on both sides. A good solder joint can be secured by pressing the connection part.

In addition, since the bimetallic clip is a metal material and has a structure coupled to both surfaces of the semiconductor device, there is an advantage that a heat radiation effect can be expected.

Claims (8)

In a semiconductor device in which at least one semiconductor package is stacked, Further comprising a bimetallic clip fitted and coupled to the top and bottom semiconductor packages, The bimetallic clip, A compression plate installed in parallel with each other and contacting and pressing the uppermost and lowermost semiconductor packages, respectively; Bimetal clip coupled semiconductor device comprising a; connecting plate for connecting both ends of the pressing plate. The bimetallic clip of claim 1, wherein the connection between the semiconductor packages is electrically connected by solder balls, and the solder balls formed on the lower surface of the lowermost semiconductor package are formed in an area spaced apart from the pressing plate. This combined semiconductor device. The semiconductor device of claim 1, further comprising an adhesive interposed between the top and bottom semiconductor packages and the pressing plate. A module substrate; At least one semiconductor package mounted on at least one surface of the module substrate; And a bimetal clip inserted into and coupled to both sides of the module substrate. The bimetallic clip, A pressing plate which is installed in parallel with each other and is pressed against the both sides of the module substrate; Bimetal clip coupled semiconductor device comprising a; connecting plate for connecting both ends of the pressing plate. The semiconductor package of claim 4, wherein at least one semiconductor package is mounted on one surface of the module substrate, and the bimetal clip is coupled to a surface opposite to an upper surface of the semiconductor packages and a surface of the module substrate. Semiconductor device with bimetal clip The bimetal clip of claim 5, wherein at least one semiconductor package is mounted on both surfaces of the module substrate, and the bimetal clip is coupled to upper surfaces of semiconductor packages on both sides of the module substrate. Semiconductor device. The bimetallic clip-coupled semiconductor device according to claim 4, wherein the bimetallic clip has a cross section having a “⊃” shape, and the pressing plate coupled to the semiconductor packages is formed of an uneven plate. . The method of claim 4, wherein the bimetallic clip is independently coupled to each semiconductor package mounted on the module substrate, and the pressing plate coupled to the semiconductor package has a “U” shape. A semiconductor device having a bimetal clip coupled thereto.

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