JP2001308122A - Method of manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily manufacture a semiconductor device with connection bumps of conductive parts piercing semiconductor elements. SOLUTION: The manufacturing method comprises a step of forming through- holes 14 piercing the thickness of a semiconductor element 10, positioning and supporting the semiconductor element on a first surface of a support jig 20 so as to communicate the through-hole with a recess 20a formed at a position corresponding to the through-hole into the first surface of the support jig 20, bonding the end of a conductive wire 24 to the recess of the jig 20 through the through-hole 14, leading out a specified length of the conductive wire from the through-hole, cutting the conductive wire 24, clipping the semiconductor element 10 between the support jig 20 and a squeezing jig 30 having a recess 30a of a larger aperture than that of the through-hole at a portion to contact the cut part of the conductive wire 24, thereby squeezing the conductive wire 24 to form an outside connecting bump 40 projecting from both surfaces of the semiconductor element to both ends, and separating the support jig 20 supporting the semiconductor element from the outside connecting bump 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly, to a semiconductor device having a conductive portion which penetrates a semiconductor element in a thickness direction and electrically connects the front and back surfaces of the semiconductor element. And a method for producing the same.

[0002]

2. Description of the Related Art A semiconductor device having a plurality of semiconductor elements mounted on a circuit board has been conventionally used as a multi-chip module (MCM) or the like. However, when a plurality of semiconductor elements are mounted two-dimensionally on a circuit board, it is necessary to secure a large mounting space. As a more compact mounting method, a method of stacking the semiconductor elements themselves and three-dimensionally mounting them. Is considered. When semiconductor elements are stacked and mounted on a circuit board, the front and back surfaces of the semiconductor elements must be electrically connected. As a method of electrically connecting the front and back surfaces of the semiconductor element, a through hole is provided in the semiconductor element, and the through hole is filled with a conductive material such as a metal or a conductive resin to electrically connect the front and back surfaces of the semiconductor element. There is a method of forming a conductive portion (Japanese Patent Application Laid-Open No. 8-306724).

FIG. 8 shows a manufacturing process for forming a conductive portion for electrically connecting the front and back surfaces of the semiconductor element 10. Fig. 8 (a)
FIG. 8 is a cross-sectional view of the semiconductor element 10 on which the electrode terminals 12 are formed, and FIG. 8B shows a state where the through holes 14 are formed at the positions of the electrode terminals 12. The through hole 14 may be formed at the same position as the position of the electrode terminal 12, or may be formed at a position different from the position where the electrode terminal 12 is formed and at a position that does not hinder the function of the semiconductor element 10. . In this case, the electrode terminals 12 and the through holes 14 are electrically connected by a conductor pattern.
FIG. 8C shows a state in which a conductive portion 16 is formed by filling the through hole 14 with a conductive resin, and FIG. 8D shows an external connection terminal 18 joined to the conductive portion 16 on the lower surface of the semiconductor element 10. Indicates the status.

The semiconductor device 11 shown in FIG.
Since the front and back surfaces of the semiconductor element 10 are electrically connected via the semiconductor device 6, the semiconductor element 10 can be mounted with the surface on which the electrode terminals 12 are formed facing upward, so that the plurality of semiconductor devices 11 are stacked. And electrically connected to each other. In the manufacturing process shown in FIG. 8, the individual semiconductor element 10 can be manufactured as a workpiece, or a semiconductor wafer on which a large number of semiconductor elements are formed can be manufactured as a workpiece. .

[0005]

As described above, when the conductive portion 16 is formed by forming the through hole 14 in the semiconductor element 10 as described above, the conventional method is to fill the through hole 14 with a conductive resin or by plating. For example, a method of forming a conductive portion 16 on the substrate 14 is performed. However, when a conductive resin is used, the electrical connection resistance increases, so that a semiconductor device using such a semiconductor element 10 has a problem in that high-speed signal characteristics deteriorate. Further, in the case where the conductive portion 16 is formed by plating, it is necessary to perform a process of covering a portion where no plating is to be adhered with a resist film, and there is a problem that a working process is complicated. In addition, there is a problem that a crack occurs in the semiconductor element due to a thermal stress caused by a difference in thermal expansion coefficient between the conductive portion 16 and the semiconductor element (silicon).

SUMMARY OF THE INVENTION The present invention has been made to solve these problems, and an object of the present invention is to provide a highly reliable semiconductor device having a conductive portion for electrically connecting the front and back surfaces of a semiconductor element. It is an object of the present invention to provide a method of manufacturing a semiconductor device in which a device can be easily manufactured and semiconductor elements can be easily stacked three-dimensionally.

[0007]

To achieve the above object, the present invention comprises the following arrangement. That is, a through hole penetrating the semiconductor element in the thickness direction is formed in an electrode terminal formed on one surface of the semiconductor element or a land portion formed by being electrically connected to the electrode terminal. The concave portion of the support jig was formed by forming a concave portion having an opening diameter larger than the opening diameter of the through hole corresponding to the position where the through hole was formed. The through-hole and the concave portion are aligned and supported so that they communicate with each other, the end of the conductive wire is bonded to the concave portion of the support jig through the through-hole, and the conductive wire is passed through the through-hole for a predetermined length. The crushing jig and the support jig, in which a recess having an opening diameter larger than the opening diameter of the through hole is formed at a portion where the cut portion of the conductive wire comes into contact with the drawn out and cut conductive wire, With the conductive element sandwiching the semiconductor element Processed to crush wood, after both end portions from both sides of the semiconductor element is molded with external connection bumps protruding, and separating the support jig that supports the semiconductor element from the external connection bumps.

The use of a gold wire as the conductive wire can reduce the electrical resistance of the external connection bump and improve the electrical characteristics of the semiconductor device. This is effective in that the thermal stress generated between them can be suitably reduced. Further, by using a jig in which the inner surface of the concave portion is covered with a metal layer as the support jig, it is possible to easily form the bump for external connection, and to improve the reliability of the electrical connection of the bump for external connection. There is an advantage that is increased. Further, a jig having a hemispherical concave portion is used as the support jig and the crushing jig. Further, the support jig is separated from the external connection bumps by removing the support jig by etching.

[0009]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Figures 1, 2,
FIG. 3 is an explanatory view showing a manufacturing process of the semiconductor device according to the present invention. FIG. 1 shows a case where a through hole 14 is formed in a semiconductor element 10,
FIG. 2 shows a process until the gold wire 24 is bonded to the supporting jig 20 supporting the semiconductor element 10 through the through hole 14.
FIG. 3 shows a process until the gold wire 24 is crushed by the support jig 20 and the crushing jig 30 to form the external connection bumps 40. FIG. A step of obtaining a semiconductor device formed with is shown.

FIG. 1A is a sectional view showing a semiconductor element 10 to be processed. The semiconductor device 10 has an electrode terminal 12 formed on the upper surface side. FIG. 1B shows a state in which a through hole 14 is formed in a portion of the semiconductor element 10 where the electrode terminal 12 is formed. The through holes 14 can be formed by irradiating the semiconductor element 10 with laser light. As a method using laser light, water is radiated into a column having a diameter of about 50 μm toward a portion where the through hole 14 of the semiconductor element 10 is formed, and the laser light is transmitted through the column to transmit the laser light to the semiconductor element 10. Is applied to form the through holes 14.

FIG. 4 is a plan view showing a state in which the through-hole 14 is formed in the thickness direction of the semiconductor element 10. In the present embodiment, a through hole 14 is formed at the center of the electrode terminal 12. The electrode terminal 12 is formed in a rectangular shape having one side of about 80 μm, and the through hole 14 is formed to have an opening diameter of about 50 μm. The reason why the opening diameter of the through hole 14 is set smaller than that of the electrode terminal 12 is to ensure that the external connection bumps 40 formed in the through hole 14 and the electrode terminal 12 are electrically connected.

Note that the portion where the through hole 14 is formed is not necessarily limited to the center position of the electrode terminal 12. That is, the through hole 14 may be formed at a position deviated from the center of the electrode terminal 12 and at a position overlapping the region of the electrode terminal 12, or at a position separated from the position where the electrode terminal 12 is formed. May be formed, and the through hole 14 and the electrode terminal 12 may be electrically connected by a conductor pattern. Since the external connection bumps 40 are formed at the positions where the through holes 14 are formed, the semiconductor devices on which the external connection bumps 40 are formed are stacked and the through holes 14 are formed in consideration of the three-dimensional mounting of the semiconductor device. Set the placement.

FIG. 1C shows a semiconductor device 10 supported by a support jig 2.
It shows a state where it is positioned and supported by zero. Support jig 20
Is a jig for supporting the semiconductor element 10 and the semiconductor element 1
The concave portion 2 is aligned with each position of the through hole 14 formed at
0a, and a metal layer 22 made of palladium or gold is formed on the inner surface of the recess 20a by plating or the like. The concave portion 20a is for forming the end of the bump in a hemispherical shape when the external connection bump 40 is formed.
The inner surface shape of Oa is formed in a hemispherical shape according to the shape of the bump. The metal layer 22 becomes a part of the external connection bump 40. The support jig 20 is removed from the semiconductor element 10 after forming the external connection bumps 40 in all the through holes 14. Therefore, a material that can be easily removed by etching or the like, such as a glass plate or a copper plate, is used.

FIG. 1 (d) shows a step of erecting a gold wire 24 in the through hole 14 using a wire bonding tool 23. Since the concave portion 20a formed in the support jig 20 is located immediately below the through hole 14 and the metal layer 22 is located at the bottom of the through hole 14, the tool 23 is inserted into the through hole 14 so that the metal layer 22 is formed. The gold wire 24 can be wire-bonded. FIG. 1D shows a state in which a ball portion formed at the tip of the gold wire 24 is bonded to the metal layer 22.

FIG. 1E shows a state in which the tool 23 is pulled up above the through hole 14 and the gold wire 24 is drawn out above the opening of the through hole 14. FIG. 1 (f) shows the drawn gold wire 2
4 is cut into a predetermined length. The gold wire 24 can be cut off like a tear. By pulling out the gold wire 24 above the opening of the through-hole 14 and cutting it, the gold wire 24 is supported by the support jig 20 and the through-hole 1
4 stands up and is supported. Note that the cut length of the gold wire 24 is a length necessary to form a bump projecting from the front and back surfaces of the semiconductor element 10 by filling the through hole 14 with gold when crushing. The thickness of the gold wire 24 used for bonding is about 25 μm.

FIG. 1 (g) shows that the gold wire 24 is wire-bonded to all the through holes 14 of the semiconductor element 10 and the gold wire 2 is
4 shows a state where the sheet 4 is cut to a predetermined length and is supported upright. In this way, the gold wire 24
Can be easily and efficiently raised by a predetermined length and supported by the support jig 20 by using a normal wire bonding method.

FIG. 2A shows the through hole 14 of the semiconductor element 10.
In this state, the crushing jig 30 is arranged above the gold wire 24 that stands up inside and is supported by the supporting jig 20. On the pressing surface of the crushing jig 30 where the cut end of the gold wire 24 contacts, a concave portion 30a for forming the external connection bump 40 into a hemispherical shape is formed. The opening diameter of the recess 30 a is set slightly larger than the opening diameter of the through hole 14,
When crushing is performed, the bump portions cover the electrode terminals 12 of the semiconductor element 10 so that the external connection bumps 40 and the electrode terminals 12 are reliably electrically connected.

FIG. 2B shows a state in which the gold wire 24 is crushed by the crushing jig 30. When the semiconductor element 10 is supported by the support jig 20 and the gold wire 24 is pressed from above the cut portion by the crushing jig 30, the through-hole 14 is filled with gold, and a hemispherical shape is formed on both surfaces of the through-hole 14. A bump is formed. FIG. 2C shows a state in which all the gold wires 24 supported by the support jig 20 are similarly crushed to form the external connection bumps 40 in the respective through holes 14.

By making the opening diameters of the recesses 20a, 30a formed in the supporting jig 20 and the crushing jig 30 slightly larger than the opening diameter of the through hole 14, the peripheral edges of both ends of the external connection bump 40 are formed. Are formed so as to lock the periphery of the opening of the through hole 14, and the external connection bump 40 is
It does not fall out of 4. When the gold wire 24 is crushed, the supporting jig 20 and the crushing jig 30 are preferably heated to about 200 ° C. so that the gold wire 24 is easily formed. Further, when the gold wire 24 is crushed, the gold wire 24 may be crushed one by one as shown in FIGS. 2A and 2B, or the gold wire 24 may be crushed at a time. You may. When the gold wire 24 is crushed at a time, for example, a crushing jig in which a concave portion for forming a hemispherical bump in accordance with the position of each through hole 14 is formed on a flat pressing surface is used. Can be processed.

As described above, the gold wire 24 is applied to the metal layer 22 of the support jig 20 by using the wire bonding tool 23.
Can be performed by the same operation as the conventional wire bonding, so that the conventional apparatus and the conventional method can be applied, and there is an advantage that the operation can be performed by an efficient operation. In addition, there is an advantage that the external connection bumps 40 can be easily and efficiently formed using the crushing jig 30.

FIG. 5 is a plan view showing a state in which the gold wire 24 is crushed and the external connection bumps 40 are formed. The figure shows a state in which the gold wire 24 is crushed and a state before the gold wire 24 is crushed. This shows that the outer diameter of the external connection bump 40 is formed to be larger than the opening diameter of the through hole 14 so that the hemispherical bump portion and the electrode terminal 12 are electrically connected. If the electrode terminals 12 are formed of a metal such as aluminum which can be easily bonded to gold, the electrical connection between the electrode terminals 12 and the external connection bumps 40 is further ensured when the gold wire 24 is crushed.

FIG. 6 shows an example in which a through hole 14 is provided at a position separated from a position where the electrode terminal 12 of the semiconductor element 10 is formed. 13 denotes an electrode terminal 12 and an external connection bump 40
13a is a ring-shaped land formed near the opening of the through hole 14. The land portion 13a is connected to the conductor pattern 13 to form a circular land portion having a diameter slightly larger than that of the through hole 14, and by forming the through hole 14 in the land area, the periphery of the through hole 14 is formed. The part is formed in a ring shape.
By forming the ring-shaped land portion 13a on the periphery of the through hole 14, the external connection bump 40 abuts on the land portion 13a when the gold wire 24 is crushed to form the external connection bump 40. Thus, the external connection bumps 40 and the electrode terminals 12 are reliably electrically connected. FIG. 6 shows a state in which the land portions 13 a are formed in the through holes 14 and a state in which the external connection bumps 40 are formed in some of the through holes 14.

FIG. 3A shows a state in which the external connection bumps 40 are formed in all the through holes 14 of the semiconductor element 10 as described above. FIG. 3B shows a state in which the support jig 20 for supporting the semiconductor element 10 is removed to obtain a semiconductor device 50 in which the external connection bumps 40 are formed in the through holes 14. The semiconductor device 50 can be obtained by mechanically removing the support jig 20 from the state of FIG. 3A or chemically dissolving and removing the support jig 20. Semiconductor device 50
The bumps 40 projecting hemispherically from the surface of the semiconductor element 10 are provided at both ends of the external connection bumps 40 formed on the semiconductor device 10.
a, 40b are formed, and the electrode terminals 12 formed on the front surface of the semiconductor element 10 and the back surface of the semiconductor element 10 are electrically connected via the external connection bumps 40.

FIG. 7 shows an example in which the semiconductor device 50 manufactured by the above-described manufacturing method is mounted on a mounting board 60.
In this example, four semiconductor devices 50 are stacked.
The semiconductor devices 50 of the respective layers are electrically connected via hemispherical bump portions 40a and 40b of the external connection bumps 40, and all the semiconductor devices 50 are electrically connected. 62 is an external connection terminal attached to the mounting board 60;
Reference numeral 4 denotes an underfill material for sealing between the mounting board 60 and the mounting surface of the lowermost semiconductor device 50.

As described above, according to the semiconductor device 50 having the external connection bumps 40 formed by penetrating the semiconductor element 10 in the thickness direction, the semiconductor devices 50 can be easily stacked and mounted three-dimensionally. The mounting area can be minimized even when a plurality of semiconductor devices are mounted. Recently, thin semiconductor elements having a thickness of 100 μm have been provided, so that even when three-dimensionally stacked semiconductor devices, there is an advantage that the overall thickness of the device is not so large.

In the above-described embodiment of the method of manufacturing a semiconductor device, the required processing is performed using the individual semiconductor elements 10 as workpieces, but the semiconductor wafer on which a large number of semiconductor elements 10 are formed is processed. It is also possible to obtain individual semiconductor devices by performing similar processing as a product. When a semiconductor wafer is to be processed, a through hole is formed in each semiconductor element in a state of the semiconductor wafer, and a gold wire erected by bonding is crushed in the through hole to form a connection bump, and then a semiconductor bump is formed. The semiconductor device may be obtained by dividing the wafer into individual pieces.

In the above-described embodiment, the external connection bumps 40 are formed using gold wires. However, other conductive wires such as copper wires and solder wires can be used instead of gold wires. When these conductive wires are used, the processing method is the same as in the above embodiment. According to the method of forming the external connection bumps 40 by crushing the gold wire 24, no void is generated in the conductive portion, and the electrical resistance of the conductive portion can be reduced. There is an advantage that electrical characteristics such as high-speed signal characteristics of the device can be improved. Further, by forming the external connection bumps 40 of gold, it is possible to obtain the reliability and reliability of the electrical connection.

[0028]

According to the method of manufacturing a semiconductor device according to the present invention, as described above, it is possible to easily manufacture a semiconductor device having an external connection bump as a conductive portion provided through a semiconductor element. Can be. As a result, it is possible to provide a semiconductor device that can be suitably used for a mounting method such as stacking and three-dimensionally mounting semiconductor devices, and the like, and it is possible to provide a remarkable effect.

[Brief description of the drawings]

FIG. 1 is an explanatory view illustrating a method for manufacturing a semiconductor device according to the present invention.

FIG. 2 is an explanatory view illustrating a method for manufacturing a semiconductor device according to the present invention.

FIG. 3 is an explanatory view illustrating a method for manufacturing a semiconductor device according to the present invention.

FIG. 4 is a plan view showing a state in which a through hole is formed in the semiconductor element.

FIG. 5 is a plan view showing a state in which an external connection bump is formed in a through hole.

FIG. 6 is a plan view showing a state in which a bump for external connection is formed in a through hole.

FIG. 7 is a cross-sectional view showing a state where the semiconductor device is mounted.

FIG. 8 is an explanatory view showing a conventional method for manufacturing a semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Semiconductor element 12 Electrode terminal 13 Conductor pattern 13a Land part 14 Through hole 16 Conducting part 18 Connection terminal 20 Support jig 20a Depression 22 Metal layer 23 Tool 24 Gold wire 30 Squeezing jig 30a Depression 40 External connection bump 40a, 40b Bump part 50 Semiconductor device 60 Mounting board

Claims (5)

[Claims] 1. A through hole penetrating a semiconductor element in a thickness direction is formed in an electrode terminal formed on one surface of a semiconductor element or a land portion formed by being electrically connected to the electrode terminal. The semiconductor element having the through-hole formed therein is formed in such a manner that the concave portion of the supporting jig in which a concave portion having an opening diameter larger than the opening diameter of the through hole is formed corresponding to the position where the through hole is formed. Positioning and supporting the through hole and the recess so that the formed surface communicates with the formed surface, bonding the end of the conductive wire to the recess of the support jig through the through hole, and transferring the conductive wire from the through hole. A squeezing jig having a concave portion having an opening diameter larger than the opening diameter of the through hole formed at a portion where the cut portion of the conductive wire comes into contact with the conductive wire rod by drawing out the predetermined length, and With the jig sandwiching the semiconductor element After crushing the conductive wire to form external connection bumps whose both ends project from both surfaces of the semiconductor element, a support jig for supporting the semiconductor element is separated from the external connection bump. A method for manufacturing a semiconductor device. 2. The method for manufacturing a semiconductor device according to claim 1, wherein a gold wire is used as the conductive wire. 3. The method for manufacturing a semiconductor device according to claim 1, wherein a jig having an inner surface of the recess covered with a metal layer is used as the support jig. 4. The method for manufacturing a semiconductor device according to claim 1, wherein a jig having a hemispherical concave portion is used as the supporting jig and the crushing jig. 5. The method of manufacturing a semiconductor device according to claim 1, wherein the separation of the support jig from the external connection bumps is performed by removing the support jig by etching. Method.