JP2002270720A - Semiconductor device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems of damage to individual semiconductor elements and the residual stress and the problem concerning the reliability since a warp occurs as a wafer when forming a semiconductor device by packaging it on the wafer level. SOLUTION: Since a second insulating resin 11 where thermal expansion balance is taken with a first insulating resin 10 on the surface is made on the rear face of a semiconductor chip 9 as a semiconductor device, this method can prevent the warp of the semiconductor device even if thermal stress occurs at mounting of a board, and a highly reliable CSP type of semiconductor device can be materialized. Moreover, this method can materialize the semiconductor device which realizes thinning together with the chip sizing since the semiconductor chip 9 itself is a thinned one.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device called a chip size package (CSP) and a method of manufacturing the same, and more particularly, to a semiconductor device having a chip size and a thin thickness realized at a semiconductor wafer level and a method of manufacturing the same. It is about the method.

[0002]

2. Description of the Related Art In recent years, as a semiconductor device in which a semiconductor chip is packaged, a CSP type semiconductor device having the same outer size as the semiconductor chip has been developed. Above all, a technique for packaging individual semiconductor chips at a semiconductor wafer level to realize a CSP type semiconductor device has been actively developed.

A conventional wafer-level CSP type semiconductor device and a method of manufacturing the same will be described below.

First, a conventional semiconductor device will be described with reference to FIG. 5A and 5B are views showing a conventional CSP type semiconductor device. FIG. 5A is a sectional view, and FIG. 5B is a plan view. Note that the cross-sectional view of FIG. 5A shows a main cross-section taken along the line A-A1 in the plan view of FIG. 5B.

[0005] As shown in FIG.
A semiconductor device having a rectangular chip shape, having a plurality of electrode pads 1 on its surface, and an insulating resin 3 such as an epoxy resin covering the surface of the semiconductor chip 2 excluding the electrode pads 1. Are provided on each of the electrode pads 1 and are electrically connected to each other. The protruding electrodes 4 are disposed on the surface of the semiconductor chip 2 with their tops exposed from the surface of the insulating resin 3. .

In the conventional semiconductor device, the protruding electrode 4 is made of a conductive material such as gold (Au), copper (Cu), or solder, and has a bump shape.

Next, a conventional method for manufacturing a semiconductor device will be described with reference to the drawings. 6 and 7 are cross-sectional views showing main steps of a conventional method for manufacturing a semiconductor device.

First, as shown in FIG. 6A, a plurality of semiconductor elements 5 having a plurality of electrode pads 1 on the surface are provided in the same plane.
To prepare a semiconductor wafer 7 divided into chip regions. Here, the thickness is 2 in advance by back grinding.
A semiconductor wafer 7 ground to a thickness of about 50 [μm] is prepared. Naturally, an integrated circuit is formed on the surface of each semiconductor element 5.

Next, as shown in FIG. 6B, the electrode pads 1 on the surface of each semiconductor element 5 of the prepared semiconductor wafer 7 are formed.
The protruding electrodes 4 are formed of a conductive material such as gold, copper, and solder, respectively. The projection electrode 4 is formed by a method such as a plating method or a wire bonding method of mechanically joining a conductive material.

Next, as shown in FIG. 6C, the surface of the semiconductor wafer 7 is covered with an insulating resin 3 such as an epoxy resin by exposing the protruding electrodes 4 on the electrode pads 1. Here, except for the dicing line 6, the insulating resin 3 is coated on the surface of each semiconductor element 5 in units of individual semiconductor elements 5, but the insulating resin 3 covers the entire surface of each semiconductor element 5 of the semiconductor wafer 7. May be coated.

Then, as shown in FIG. 7A, the semiconductor wafer 7 is cut by a dicing line to obtain a semiconductor device 8 in chip units. FIG. 7B shows one chip-shaped semiconductor device 8 cut and separated from a semiconductor wafer.

As described above, in the conventional method of manufacturing a semiconductor device, individual semiconductor chips are packaged at a wafer level by performing electrode formation, resin coating for surface protection, dicing, and the like in the state of a semiconductor wafer to form a CSP.
Type semiconductor device.

[0013]

However, the conventional semiconductor device is a semiconductor device having a chip size, but not a thinner semiconductor device. Also, since an insulating resin is formed on the surface of a semiconductor chip as a semiconductor device, when a semiconductor device is mounted on a mounting substrate such as a printed circuit board, if thermal stress is applied to the semiconductor device due to mounting conditions, environment, etc. In addition, the semiconductor device itself may be warped, and the integrated circuit in the semiconductor chip may be damaged, resulting in a lack of reliability as a product. Particularly, when the thickness of the semiconductor device itself is reduced, there is a problem that warpage is likely to occur on the side where the difference in thermal expansion coefficient is large. Furthermore, warpage of the semiconductor device due to stress may reduce the reliability of bonding between the bump electrode and the mounting substrate.

In the conventional method of manufacturing a semiconductor device, since packaging is performed at a semiconductor wafer level,
In particular, when an insulating resin is formed on a semiconductor wafer by resin coating for surface protection, warpage occurs as a semiconductor wafer, which hinders division by dicing into individual semiconductor devices and a problem of damage to semiconductor elements. was there. When a semiconductor wafer has a warp and is divided into individual semiconductor devices in that state, the warp is eliminated in appearance, but on the contrary, the semiconductor element (semiconductor chip) and the insulating resin on the surface are not. There is also a problem that a residual stress is left in between, resin peeling and damage to the integrated circuit element.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. In packaging a semiconductor device at a semiconductor wafer level to form a semiconductor device, a semiconductor wafer is prevented from warping and damage to an integrated circuit element is eliminated. It is an object of the present invention to provide a semiconductor device and a method of manufacturing the same, and an object of the present invention to provide a thinner semiconductor device and a method of manufacturing the same.

[0016]

In order to solve the above-mentioned conventional problems, a semiconductor device according to the present invention is a chip-shaped semiconductor device, comprising: a semiconductor chip having electrode pads on its surface; A first insulating resin covering the surface of the semiconductor chip except for the first insulating resin, a protruding electrode electrically connected to the electrode pad and arranged on the surface of the semiconductor chip, and a back surface excluding a side surface region of the semiconductor chip; A semiconductor device comprising a second insulating resin covering a region.

More specifically, the semiconductor chip is a semiconductor device whose back surface is thinned to a thickness of 100 [μm] or less by grinding.

Further, the present invention is a semiconductor device in which a protruding electrode is provided on an electrode pad.

Further, the projection electrode is provided on the surface of the first insulating resin covering the surface of the semiconductor chip, and the projection electrode and the electrode pad of the semiconductor chip are connected by conductor wiring in a semiconductor device. is there.

Further, the first insulating resin and the second insulating resin are semiconductor devices having the same thickness.

As described above, the semiconductor device of the present invention comprises:
As a semiconductor device, a second insulating resin having a thermal expansion balance with the first insulating resin on the front surface is formed on the back surface of the semiconductor chip. This is a highly reliable CSP type semiconductor device in which no warpage occurs as a semiconductor device. Further, since the semiconductor chip itself of the semiconductor device is also a semiconductor chip thinned by grinding, it is possible to realize a semiconductor device that realizes a reduction in chip size and thickness. In particular, since the thickness of the semiconductor chip is 100 [μm] or less, for example, 50 [μm], an extremely thin CSP type semiconductor device can be obtained.
m] even if the thickness is small.

Further, in the method of manufacturing a semiconductor device according to the present invention, a plurality of semiconductor elements having a plurality of electrode pads on the surface are provided in the same plane, and each individual semiconductor element is divided into a chip area by a dicing line. A step of preparing a semiconductor wafer, a step of forming a protruding electrode using a conductive material on each of the electrode pads on the surface of each semiconductor element of the semiconductor wafer, and a step of forming the protruding electrode on the electrode pad using the conductive material. Exposing and coating with a first insulating resin; grinding the back surface of the semiconductor wafer to form a thin semiconductor wafer; and coating the back surface of the thin semiconductor wafer with a second insulating resin. A method of manufacturing a semiconductor device, comprising: a step of coating; and a step of cutting the thin semiconductor wafer by a dicing line to obtain a semiconductor device in chip units. It is.

More specifically, in the step of grinding the back surface of the semiconductor wafer to form a thin semiconductor wafer, a method of manufacturing a semiconductor device is performed in a state where the front surface of the semiconductor wafer is adhered and fixed to a sheet member. is there.

In the step of grinding the back surface of the semiconductor wafer to form a thin semiconductor wafer, the method is a method of manufacturing a semiconductor device in which the thickness of the semiconductor wafer is ground to a small thickness of 100 [μm] or less.

A step of exposing the protruding electrode on the electrode pad to cover the surface of the semiconductor wafer with the first insulating resin; and a step of coating the back surface of the thin semiconductor wafer with the second insulating resin. The first insulating resin and the second insulating resin
The insulating resin is a method of manufacturing a semiconductor device in which the insulating resin is covered with the same thickness.

As described above, in the method of manufacturing a semiconductor device according to the present invention, when packaging at the semiconductor wafer level, the first insulating resin is formed on the front surface and then adhered to a sheet to adhere to the back surface of the semiconductor wafer. The first insulating resin formed on the back surface of the semiconductor wafer is balanced with the first insulating resin formed on the front surface by preventing the occurrence of warpage while maintaining a second thermal insulation balance. Forming a conductive resin and dividing it into individual semiconductor devices, so that individual semiconductor devices can be obtained without warpage, thereby realizing a highly reliable semiconductor device that realizes a reduction in chip size and thickness. Can be. In particular, the thickness of the semiconductor chip is 100 [μm] or less, for example, 50 [μm].
m], an extremely thin CSP type semiconductor device can be obtained.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a semiconductor device and a method for manufacturing the same according to the present invention will be described below.

First, the semiconductor device of the present embodiment will be described with reference to the drawings. 1A and 1B are views showing a CSP type semiconductor device according to the present embodiment. FIG. 1A is a sectional view, and FIG. 1B is a plan view. The cross-sectional view of FIG. 1A shows a main cross-section taken along a line BB1 in the plan view of FIG. 1B.

As shown in FIG. 1, the semiconductor device according to the present embodiment is a thin semiconductor device in the form of a chip, and has a semiconductor chip 9 having a peripheral electrode pad 1 on its surface.
A first insulating resin 10 covering the surface of the semiconductor chip 9 except for the electrode pads 1 with a uniform thickness; and a protruding electrode 4 electrically connected to the electrode pads 1 and arranged on the surface of the semiconductor chip 9. And a second insulating resin 11 covering the back surface region of the semiconductor chip 9 excluding the side surface region with a uniform thickness. The back surface of the semiconductor chip 9 is 100 [μm] or less, for example, 50 [μm] by grinding.
m], which is a thinned semiconductor chip as a semiconductor device.

Further, as shown in FIG. 1, in the semiconductor device of the present embodiment, the protruding electrode 4 is provided directly on the electrode pad 1.

In the semiconductor device of the present embodiment, the first
The insulating resin 10 and the second insulating resin 11 are provided with thicknesses equivalent to each other, and are provided so as to balance thermal expansion due to heat history at the time of mounting the substrate. Therefore, the semiconductor device does not warp due to thermal stress generated due to thermal history or the like at the time of mounting the substrate, and is a highly reliable CSP type semiconductor device.

In this embodiment, the first insulating resin 1
0, the thickness of the second insulating resin 11 is 5 to 15 [μm]
The thickness is preferably 10 [μm]. That is, with respect to the thickness of the semiconductor chip 9, the first insulating resin 1
The second insulating resin 11 is provided so as to balance the warpage due to zero.
The appropriate thickness of the insulating resin 11 is set according to the thickness of the semiconductor chip 9.

As described above, in the semiconductor device of the present embodiment, the second insulating resin 11 having thermal expansion balance with the first insulating resin 10 on the front surface is formed on the back surface of the semiconductor chip 9 as a semiconductor device. Therefore, the semiconductor device does not warp due to thermal stress generated by thermal history or the like at the time of substrate mounting, and is a highly reliable CSP type semiconductor device. In addition, since the semiconductor chip 9 itself of the semiconductor device is also a semiconductor chip thinned by grinding, it is possible to realize a semiconductor device that realizes thinning as well as chip size. In particular, the thickness of the semiconductor chip 9 is 100 [μm]
Since the thickness is, for example, 50 [μm] below, an extremely thin CSP type semiconductor device can be obtained.
Even if the thickness is as thin as [μm], the structure can prevent warpage.

Next, a method of manufacturing the semiconductor device according to the present embodiment will be described. 2 and 3 are cross-sectional views showing main steps of the method for manufacturing a semiconductor device according to the present embodiment.

First, as shown in FIG. 2A, a plurality of semiconductor elements 5 having a plurality of electrode pads 1 on the surface are provided in the same plane.
A semiconductor wafer 7 divided into chip regions by (scribe lines) is prepared. Naturally, an integrated circuit is formed on the surface of each semiconductor element 5. Here, the thickness is previously 250 [μ] by back grinding.
m] Although the semiconductor wafer 7 ground to a thickness is prepared, a semiconductor wafer that is not back-ground because a back surface is ground in a later process may be used.

Next, as shown in FIG. 2B, the electrode pads 1 on the surface of each semiconductor element 5 of the prepared semiconductor wafer 7 are formed.
The protruding electrodes 4 are formed of a conductive material, respectively. In addition, a conductive material such as gold, copper, or solder is used as the conductive material, and the bump electrode 4 is formed by a method such as a plating method or a wire bonding method of mechanically bonding the conductive material.

Next, as shown in FIG. 2C, the projecting electrodes 4 on each electrode pad 1 are placed on the surface of the semiconductor wafer 7.
Is exposed and covered with the first insulating resin 10. Here, the top of the protruding electrode 4 is covered with the first insulating resin 10 so as to protrude, but as a coating method, it is covered with an epoxy-based thermosetting resin by a transfer molding method, a coating method, or a potting method. . In this case, the coating thickness is 5 to 15 μm, and in the present embodiment, it is 10 μm.
[Μm] thick.

In the present embodiment, the first insulating resin 10 is coated over the entire surface of each semiconductor element 5 of the semiconductor wafer 7. However, except for the dicing line 6, the individual semiconductor elements 5 are separated and separated. The insulating resin 3 may be coated on each surface of the semiconductor element 5. When the front surface is coated with the insulating resin 10, the back surface is adhered to a resin sheet, so that the coated insulating resin can be prevented from warping due to thermosetting shrinkage during slow cooling. Then, before the grinding step of the next step, the front side of the semiconductor wafer 7 on which the first insulating resin 10 is formed is attached to a resin sheet, and then the resin sheet on the back side is peeled off to prevent temporary warpage. Can be suppressed.

Next, as shown in FIG. 2D, the front side of the semiconductor wafer 7 on which the first insulating resin 10 is formed is bonded and fixed to a resin sheet 12, and the back side of the semiconductor wafer 7 is ground with a grinder. Grind and thin. In this step, the semiconductor wafer 7 having a thickness of 250 [μm]
The thickness is reduced to 0 [μm] or less, for example, 50 [μm].
Here, even if the thickness of the semiconductor wafer 7 having the first insulating resin 10 formed on the surface is reduced to, for example, 50 [μm], the front surface side in the warp direction is bonded and fixed to the resin sheet 12. Thus, it is possible to maintain a state in which the occurrence of warpage is suppressed. Therefore, the thickness of the resin sheet 12 to be used should be such that it can resist the warpage of the semiconductor wafer 7. Further, as the resin sheet 12, it is preferable to use a resin sheet on which an ultraviolet-curable adhesive is formed, and an excessive force is applied when the thinned semiconductor wafer 7 is peeled off from the sheet, so as not to be damaged or cracked. To

Next, as shown in FIG. 3A, the second insulating resin 11 is applied to the back surface of the semiconductor wafer 7 while the thin semiconductor wafer 7 of the previous process is still attached to the resin sheet 12. Cover with. Here, the thickness of the second insulating resin 11 is equal to the thickness of the first insulating resin 10 on the surface side of the semiconductor wafer 7 already formed, for example, 10 [μm].
The second insulating resin 1 is formed so as to balance wafer warpage caused by the first insulating resin 10.
The appropriate thickness of the first insulating resin 10 and the second insulating resin 11 is set according to the thickness of the semiconductor wafer 7.

Next, as shown in FIG. 3B, the semiconductor wafer 7 having the first insulating resin 10 formed on the front side and the second insulating resin 11 formed on the back side is separated and separated from the resin sheet. .

Then, as shown in FIG. 3C, the thin semiconductor wafer 7 is cut by a dicing line,
This is to obtain a semiconductor device 13 for each chip. In addition,
At the time of dicing, since the entire surface of the semiconductor wafer is covered with the first insulating resin, the dicing line may not be recognized in some cases. However, dicing can be performed by recognizing the dicing line by infrared recognition.

FIG. 3D shows one chip-shaped thin semiconductor device 13 cut and separated from the semiconductor wafer 7. As shown in FIG. 1, the semiconductor device shown in FIG. 3D has a semiconductor chip 9 having electrode pads 1 on the surface and a first insulating material covering the surface of the semiconductor chip 9 excluding each electrode pad 1. A protruding electrode 4 electrically connected to the resin 10 and each of the electrode pads 1 and disposed on the surface of the semiconductor chip 9
And a second insulating resin 11 covering a back surface region excluding a side surface region of the semiconductor chip 9.

As described above, in the method of manufacturing a semiconductor device according to the present embodiment, when packaging at the semiconductor wafer level, the first insulating resin 10 is formed on the surface and then adhered to the resin sheet 12 to form the semiconductor wafer. The back surface of the semiconductor wafer 7 is thinned by grinding with a grinder, and warpage is prevented in that state, and the thermal expansion balance between the back surface of the semiconductor wafer 7 and the first insulating resin 10 formed on the front surface is maintained. Since the second insulating resin 11 is formed and divided into individual semiconductor devices 13, individual semiconductor devices can be obtained without warpage, so that the reliability is reduced as well as the chip size is reduced. Semiconductor device with high reliability can be realized. Especially the thickness of the semiconductor chip is 10
Since the thickness is 0 [μm] or less, for example, 50 [μm], an extremely thin CSP type semiconductor device can be obtained.

Next, another embodiment of the semiconductor device of the present invention will be described. FIG. 4 is a sectional view showing the semiconductor device of the present embodiment.

As shown in FIG. 4, the semiconductor device of the present embodiment is not a peripheral type semiconductor device but an area array type semiconductor device, in which a semiconductor chip 9 having an electrode pad 1 on its surface, A first insulating resin 10 covering the surface of the semiconductor chip 9 excluding the pads 1, a projecting electrode 4 electrically connected to each electrode pad 1 and arranged on the surface of the semiconductor chip 9, The projection electrode 4 is formed on the surface of the first insulating resin 10 covering the surface of the semiconductor chip 9 and the second insulating resin 11 covering the back surface region excluding the side surface region. The protruding electrodes 4 are provided and the electrode pads 1 of the semiconductor chip 9 are re-wired and connected by a conductor wiring 14 such as gold (Au) or copper (Cu). Therefore, the semiconductor device shown in FIG. 4 is an area pad type semiconductor device, and the bump electrode 4 which is an external electrode is provided on the semiconductor chip 9.
Are arranged in an array, which is a semiconductor device compatible with multi-pin configuration.

[0047]

As described above, in the semiconductor device of the present invention, the second insulating resin having thermal expansion balance with the first insulating resin on the front surface is formed on the back surface of the semiconductor chip as the semiconductor device. In addition, the semiconductor device does not warp due to thermal stress generated by thermal history or the like at the time of substrate mounting, and is a highly reliable CSP type semiconductor device. Further, since the semiconductor chip itself of the semiconductor device is also a semiconductor chip thinned by grinding, it is a semiconductor device which realizes a reduction in thickness as well as chip size.

In the method of manufacturing a semiconductor device according to the present invention, when packaging at the semiconductor wafer level, a first insulating resin is formed on the front surface, then adhered to a sheet and ground from the back side of the semiconductor wafer by a grinder. Forming a second insulating resin having a thermal expansion balance with the first insulating resin formed on the front surface of the back surface of the semiconductor wafer while preventing warpage from occurring. In addition, since the semiconductor device is divided into individual semiconductor devices, individual semiconductor devices can be obtained without warpage. Therefore, a highly reliable semiconductor device having a reduced chip size and a reduced thickness can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a semiconductor device according to an embodiment of the present invention;

FIG. 2 is a sectional view showing the method for manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 3 is a sectional view showing the method of manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 4 is a diagram showing a semiconductor device according to one embodiment of the present invention;

FIG. 5 illustrates a conventional semiconductor device.

FIG. 6 is a sectional view showing a conventional method for manufacturing a semiconductor device.

FIG. 7 is a sectional view showing a conventional method of manufacturing a semiconductor device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrode pad 2 semiconductor chip 3 insulating resin 4 projecting electrode 5 semiconductor element 6 dicing line 7 semiconductor wafer 8 semiconductor device 9 semiconductor chip 10 first insulating resin 11 second insulating resin 12 resin sheet 13 semiconductor device 14 conductor wiring

Claims (9)

[Claims] 1. A chip-shaped semiconductor device, comprising: a semiconductor chip having an electrode pad on a surface; a first insulating resin covering a surface of the semiconductor chip excluding the electrode pad; A semiconductor device, comprising: a bump electrode electrically connected and arranged on a front surface of the semiconductor chip; and a second insulating resin covering a back surface region excluding a side surface region of the semiconductor chip. 2. The semiconductor device according to claim 1, wherein the back surface of the semiconductor chip is thinned to a thickness of 100 [μm] or less by grinding. 3. The semiconductor device according to claim 1, wherein a protruding electrode is provided on the electrode pad. 4. The semiconductor device according to claim 1, wherein the protruding electrode is provided on a surface of the first insulating resin covering a surface of the semiconductor chip, and the protruding electrode and an electrode pad of the semiconductor chip are connected by a conductor wiring. 2. The semiconductor device according to claim 1, wherein: 5. The semiconductor device according to claim 1, wherein the first insulating resin and the second insulating resin have the same thickness. 6. A step of preparing a semiconductor wafer having a plurality of semiconductor elements having a plurality of electrode pads on the surface in the same plane, wherein each semiconductor element is divided into chip regions by dicing lines; A step of forming a projecting electrode using a conductive material on each of the electrode pads on the surface of each semiconductor element of the semiconductor wafer; and exposing the projecting electrode on the electrode pad to expose the surface of the semiconductor wafer to a first insulating resin. A step of grinding the backside of the semiconductor wafer to form a thin semiconductor wafer; a step of coating the backside of the thin semiconductor wafer with a second insulating resin; A method of cutting a wafer with a dicing line to obtain a semiconductor device in chip units. 7. The method according to claim 6, wherein the step of grinding the back side of the semiconductor wafer to form a thin semiconductor wafer is performed with the front side of the semiconductor wafer adhered and fixed to a sheet member. Of manufacturing a semiconductor device. 8. The method according to claim 6, wherein in the step of grinding the back side of the semiconductor wafer to form a thin semiconductor wafer, the thickness of the semiconductor wafer is ground to a small thickness of 100 [μm] or less. A method for manufacturing a semiconductor device. 9. A step of exposing the protruding electrodes on the electrode pads to cover the front surface of the semiconductor wafer with a first insulating resin, and a step of coating the back surface of the thin semiconductor wafer with a second insulating resin. 7. The method according to claim 6, wherein the first insulating resin and the second insulating resin are coated with the same thickness.