JP2010003720A - Semiconductor device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the damages in the bonding part of a pad electrode and a bump electrode, and to widen the contact area of the wiring pattern of a circuit board and the bump electrode. <P>SOLUTION: After laminating a support 15 through an adhesive layer 14 to a semiconductor substrate 10 where the pad electrode 12 is arranged, a first opening 10A is formed in an area superimposed with the pad electrode 12. Then, a protective film 16 is formed which covers the inside of the first opening 10A and the back surface of the semiconductor substrate 10 and has a second opening 16A on the pad electrode 12. Then, the bump electrode 18 is formed which includes conductive paste, covers the entire first opening 10A and second opening 16A, connects to the pad electrode 12 through the second opening 16A and projects higher than the protective film 16 on the back surface of the semiconductor substrate 10. Thereafter, a laminate including the semiconductor substrate 10 and the support 15 is diced along a dicing line DL passing on the bump electrode 18 into a semiconductor chip 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a semiconductor device and a manufacturing method thereof, and more particularly to a chip size package and a manufacturing method thereof.

  In recent years, a chip size package has attracted attention as a new packaging technology. The chip size package is a small package having an outer dimension substantially the same as the outer dimension of the semiconductor chip.

  A BGA (Ball Grid Array) type semiconductor device is known as one of chip size packages. A plurality of ball-shaped bump electrodes electrically connected to pad electrodes provided on the semiconductor device are provided on the back surface of the BGA type semiconductor device.

  A configuration example of this BGA type semiconductor device will be described below. As shown in FIG. 9, an electronic device 10D is arranged on the surface of a semiconductor substrate 10 constituting this semiconductor device, and an insulating film 11 is arranged so as to cover it. Further, a support 15 is bonded to the surface of the semiconductor substrate 10 via an adhesive layer 14. The support 15 extends outside the end of the semiconductor substrate 10. A pad electrode 12 electrically connected to the electronic device 10 </ b> D is disposed on a part of the support 15 extending outside the end of the semiconductor substrate 10. The pad electrode 12 is covered with a passivation film 13.

  Further, a protective film 16 having an opening is disposed on the pad electrode 12 so as to cover the side wall and the back surface of the semiconductor substrate 10 from the end of the support 15. Further, a plating film 17 containing nickel (Ni) or the like is disposed on the pad electrode 12 in the opening of the protective film 16, and a plurality of bump electrodes 19 connected to the plating film 17 are disposed.

  When this BGA type semiconductor device is incorporated in an electronic device, each bump electrode 19 is connected to a wiring pattern (not shown) on a circuit board (not shown) such as a printed circuit board, whereby an electronic device 10D and a circuit are connected. An external circuit (not shown) mounted on the substrate is electrically connected.

Note that the BGA type semiconductor device is described in Patent Document 1.
JP 2007-242813 A

  However, in the semiconductor device described above, when the bump electrode 19 is connected to a circuit board such as a printed circuit board, stress is applied to the joint between the pad electrode 12 and the bump electrode 19 according to an external force applied to the semiconductor device. Was concentrated. Due to this stress, there is a problem that damage such as cracks occurs in the joint. In addition, since the contact area between the wiring pattern of the circuit board and the bump electrode 19 is small, there is a problem that the contact resistance increases. In addition, the manufacturing cost of the bump electrode 19 is high.

  The main features of the present invention are as follows. The semiconductor device of the present invention includes a semiconductor substrate on which an electronic device is disposed, a support that is bonded to the surface of the semiconductor substrate via an adhesive layer and extends outside the end of the semiconductor substrate, and the electronic device electrically A pad electrode formed on a portion of the support that is connected and extends to the outside of the edge of the semiconductor substrate, and a protection that covers the side wall and back surface of the semiconductor substrate from above the edge of the support and has an opening on the pad electrode A film and a conductive paste, connected to the pad electrode through the opening of the protective film, cover the entire region from the end of the support to the side wall of the semiconductor substrate, and more than the protective film on the back surface of the semiconductor substrate And a projecting electrode projecting highly.

  The method for manufacturing a semiconductor device according to the present invention also provides a semiconductor substrate on which an electronic device and a pad electrode electrically connected to the electronic device are arranged, and a support is attached to the semiconductor substrate via an adhesive layer. A step of aligning, a step of removing a part of the semiconductor substrate and forming a first opening in a region overlapping with the pad electrode, a second surface on the pad electrode covering the back surface of the first opening and the semiconductor substrate. Forming a protective film having a plurality of openings, a conductive paste, covering the entire first opening and the second opening, and connecting to the pad electrode through the second opening, A step of forming a protruding electrode that protrudes higher than the protective film on the back surface of the substrate and a laminated body including the semiconductor substrate and the support body are diced along a dicing line that passes over the protruding electrode. Characterized in that it comprises a step of releasing, the.

  According to the present invention, the stress applied to the joint between the pad electrode and the protruding electrode can be reduced, and damage such as cracks in the joint caused by the stress can be suppressed. In addition, since the contact area between the wiring pattern of the circuit board and the protruding electrode can be widened, the contact resistance can be reduced.

  Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 show the semiconductor device and the manufacturing method thereof according to the present embodiment. FIG. 1A to FIG. 8A are cross-sectional views of this semiconductor device, and one semiconductor chip 1 is included in a plurality of semiconductor devices, that is, a wafer-like semiconductor substrate 10 on which semiconductor chips 1 are formed. It is illustrated centering on the region to be formed. FIGS. 1B to 8B show a region in the vicinity of the dicing line DL when viewed from the back side of the semiconductor substrate 10 corresponding to each of FIGS. 1A to 8A. FIG.

  First, as shown in FIG. 1, a semiconductor substrate 10 made of a silicon substrate having a film thickness of, for example, about 100 to 700 μm is prepared. Here, an electronic device 10 </ b> D such as a photodiode is disposed on the surface of the semiconductor substrate 10. The electronic device 10D is covered with an insulating film 11 made of a BPSG film having a thickness of about 0.5 to 1.5 μm, for example, and is electrically connected to the electronic device 10D on the insulating film 11. The pad electrode 12 is disposed. The pad electrode 12 is disposed near the end of the semiconductor chip 1, for example, near the center of each side of the semiconductor chip 1.

  However, the pad electrode 12 is not limited to the above, and as long as it is in the vicinity of the end of the semiconductor chip 1, the pad electrode 12 may be disposed at another position, for example, in the vicinity of the apex where each side of the semiconductor chip 1 intersects. Good. In the following description, the pad electrode 12 is described as being disposed near the end of the semiconductor chip 1 and in the vicinity of the center of each side of the semiconductor chip 1.

  In this semiconductor substrate 10, a passivation film 13 such as a silicon nitride film is formed so as to cover the surfaces of the pad electrode 12 and the insulating film 11. Thereafter, an adhesive layer 14 is formed on the passivation film 13 by applying an adhesive containing an organic resin or the like, and the support 15 is bonded to the surface of the semiconductor substrate 10 through the adhesive layer 14. . The support 15 is made of a material that transmits light or a material that does not transmit light. The support 15 is made of, for example, a glass substrate and has a thickness of about 100 to 700 μm, for example.

  Next, as shown in FIGS. 2A and 2B, the semiconductor substrate 10 bonded to the support 15 is subjected to back surface grinding, and the thickness is reduced to, for example, 10 to 150 μm. To do. Further, as shown in FIGS. 3A and 3B, a region of the semiconductor substrate 10 from the region including the dicing line DL and the pad electrode 12 to the end of the semiconductor chip 1 is etched. To remove. Thereby, the first opening 10A is formed in the semiconductor substrate 10, and the insulating film 11 is exposed in the first opening 10A.

  The first opening 10A may be formed in a street shape extending along the dicing line DL (not shown) in addition to the window shape as shown in FIG. 3B. ).

  In addition, the side wall of the semiconductor substrate 10 in the first opening 10 </ b> A is preferably formed in a tapered shape toward the support 15. Thereby, the coverage of each layer formed so as to cover the semiconductor substrate 10 and the support 15 in a later step is improved.

  Next, as shown in FIG. 4, the insulating film 11 exposed in the first opening 10A is removed by etching, and the back surface of the pad electrode 12 and the back surface of the passivation film 13 are removed in the first opening 10A. To expose. Thereafter, as shown in FIGS. 5A and 5B, along the dicing line DL of the semiconductor substrate 10, the passivation film 13, the adhesive layer 14, and a part of the support 15 in the thickness direction are partially formed. The street-shaped groove 15A is formed by cutting. The groove 15 </ b> A is formed at a position where it does not contact the pad electrode 12.

  Next, as shown in FIGS. 6A and 6B, a protective film 16 is formed to cover the first opening 10 </ b> A including the inside of the groove 15 </ b> A and the back surface of the semiconductor substrate 10. In the protective film 16, a second opening 16 </ b> A is provided in a region overlapping with the pad electrode 12. The material of the protective film 16 is preferably an organic film such as a solder resist, but may be an inorganic film.

  Next, as shown in FIGS. 7A and 7B, the first opening 10A including the inside of the groove 15A and the entire second opening 16A are covered, and the semiconductor substrate 10 is covered. For example, a conductive paste containing at least one of silver (Ag) particles, copper (Cu) particles, or tin (Sn) particles is applied so as to protrude higher than the surface of the protective film 16 covering the back surface, and the conductivity A protruding electrode 18 made of a conductive paste is formed. The protruding electrode 18 is connected to the pad electrode 12 through the second opening 16A. The protruding electrode 18 is formed on a part of the dicing line DL.

  Next, as shown in FIGS. 8A and 8B, the stacked body including the semiconductor substrate 10 and the support 15 is diced along dicing lines passing over the protruding electrodes 18, thereby providing a semiconductor chip. Separate into 1. During the dicing, only the support 15, the protective film 16 in the groove 15 </ b> A, and the protruding electrode 18 are cut.

  In the semiconductor device thus completed, that is, the semiconductor chip 1, the protruding electrode 18 is connected to the pad electrode 12 through the second opening 16 </ b> A of the protective film 16, and from the end of the support 15 to the side wall of the semiconductor substrate 10. The entire region is covered and protrudes higher than the protective film 16 on the back surface of the semiconductor substrate 10.

  Then, when the semiconductor chip 1 is mounted on the wiring pattern (not shown) of the circuit board, the force applied to the protruding electrode 18 is distributed over the entire region from the end of the support 15 to the side wall of the semiconductor substrate 10. The As a result, compared with the stress applied to the joint between the pad electrode 12 and the bump electrode 19 in the conventional example shown in FIG. 9, the stress applied to the joint between the pad electrode 12 and the bump electrode 18 in the present embodiment is greatly increased. This reduces the damage such as cracks at the joint between the pad electrode 12 and the bump electrode 19 due to the stress.

  Further, when compared with the contact area between the bump electrode 19 and the circuit board wiring pattern (not shown) in the conventional example, the bump electrode 19 of the semiconductor chip 1 and the circuit board wiring pattern (not shown) in the present embodiment. Since the contact area can be greatly increased, the contact resistance can be reduced.

  Moreover, since the manufacturing cost of the bump electrode 18 in this embodiment is lower than the manufacturing cost of the bump electrode 19 in the conventional example, the manufacturing cost of the semiconductor device can be reduced.

  Further, in this semiconductor chip 1, the end of the passivation film 13 exposed at the side surface, the end of the adhesive layer 14, and the end of part of the support 15 are covered with the protective film 16, so that the semiconductor chip 1 Intrusion of moisture into the chip 1 can be prevented.

  However, when it is not necessary to consider the intrusion of moisture into the semiconductor chip 1, the step of forming the groove 15A described above may be omitted.

  Needless to say, the present invention is not limited to the above-described embodiment, and modifications can be made without departing from the scope of the invention.

  For example, in the above embodiment, the pad electrode 12 and the protruding electrode 18 are directly connected, but the present invention is not limited to this, and a plating film (not shown) is provided between the pad electrode 12 and the protruding electrode 18. It may be formed. Even in this case, the same effect as described above can be obtained.

It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing and the top view which show the semiconductor device by the embodiment of this invention, and its manufacturing method. It is sectional drawing which shows the semiconductor device by the prior art example, and its manufacturing method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor chip 10 Semiconductor substrate 10D Electronic device 10A 1st opening part 11 Insulating film 12 Pad electrode 13 Passivation film 14 Adhesive layer 15 Support body 15A Groove 16 Protective film 16A 2nd opening part
17 Plating film 18 Projection electrode 19 Bump electrode

Claims (8)

A semiconductor substrate on which electronic devices are arranged; and
A support bonded to the surface of the semiconductor substrate via an adhesive layer and extending to the outside of the end of the semiconductor substrate;
A pad electrode formed on a portion of the support that is electrically connected to the electronic device and extends outside an edge of the semiconductor substrate;
A protective film that covers the side wall and the back surface of the semiconductor substrate from the end of the support, and has an opening on the pad electrode;
The conductive paste is connected to the pad electrode through the opening of the protective film, covers the entire region from the end of the support to the side wall of the semiconductor substrate, and protects the back surface of the semiconductor substrate. And a protruding electrode protruding higher than the film.   The semiconductor device according to claim 1, wherein the protruding electrode has a surface parallel to a back surface of the semiconductor substrate.   The semiconductor device according to claim 1, wherein the conductive paste includes at least one of silver particles, copper particles, or tin particles.   4. The semiconductor device according to claim 1, wherein the protective film covers each end portion of the adhesive layer and the support body. 5. Preparing a semiconductor substrate on which an electronic device and a pad electrode electrically connected to the electronic device are arranged;
Bonding the support to the semiconductor substrate via an adhesive layer;
Removing a part of the semiconductor substrate and forming a first opening in a region overlapping with the pad electrode;
Forming a protective film having a second opening on the pad electrode, covering the first opening and the back surface of the semiconductor substrate;
It is made of a conductive paste, covers the entire first opening and the second opening, and is connected to the pad electrode through the second opening, and is higher than the protective film on the back surface of the semiconductor substrate. Forming a protruding electrode, and
And a step of dicing the laminated body including the semiconductor substrate and the support along a dicing line passing over the protruding electrode, thereby separating the semiconductor chip into a semiconductor chip.   6. The method of manufacturing a semiconductor device according to claim 5, wherein the protruding electrode has a surface parallel to a back surface of the semiconductor substrate.   The method for manufacturing a semiconductor device according to claim 5, wherein the conductive paste includes at least one of silver particles, copper particles, and tin particles. Before the step of forming the protective film,
Cutting the adhesive layer and part of the support in the thickness direction along the edge of the semiconductor chip to form a groove, and
The protective film is formed so as to extend into the groove, and after forming the protruding electrode so as to cover the protective film, by cutting the support, the protective film on the groove and the protruding electrode, The method for manufacturing a semiconductor device according to claim 5, wherein the stacked body is separated into the semiconductor chips.

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