KR101381644B1 - Bump electrode structure of semiconductor device and method for manufacturing therof - Google Patents

Abstract

The present invention provides a bump formed on an upper end of a semiconductor, at least one protruding core formed on an upper end of the bump and made of an elastic polymer material, and formed by being applied to an upper end of the bump and the protruding core. Provided are a bump electrode structure of a semiconductor device including a metal layer in contact with an electrode of a substrate, and a method of manufacturing the same.

Description

Bump electrode structure of semiconductor device and manufacturing method therefor {BUMP ELECTRODE STRUCTURE OF SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THEROF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode structure of a semiconductor device, and more particularly, to a structure of a bump electrode having a conductive elastic protrusion formed on an upper end of a bump of a semiconductor device and a method of manufacturing the same.

Four key technologies that enable the rapid development of electronics today are semiconductor technology, semiconductor packaging technology, manufacturing technology, and software technology. Semiconductor technology is developing with sub-micron line widths, more than one million cells, high speeds, and much heat dissipation. However, the packaging technology is relatively outdated, so the electrical performance of semiconductors is more important than that of semiconductors themselves. It is determined by the electrical connection accordingly.

In addition, as the performance of electronic components is improved, the number of input / output signals of the integrated circuit chip increases, and as the size of the chip is minimized, the pitch between I / O, which is an input / output signal input / output signal, is gradually decreasing. The driver IC of the large flat panel display requiring a fine pitch is reduced to 25 μm in pitch and 10 to 15 μm in interval. Also, the research on the stacking method using TSV shows that the interval between I / O is less than 10 μm. It is required.

Since the driver IC of the flat panel display requiring fine pitch is composed of ITO electrodes, only the flip chip bonding using an anisotropic conductive film (ACF) or the like is possible, and the process is simplified even in the lamination process using TSV. Laminating process using adhesives is being illuminated due to the low process temperature and the like.

Such a semiconductor packaging, that is, an adhesive for mounting a semiconductor chip is divided into anisotropic conductive and non-conductive according to the presence or absence of conductive particles. In the case of non-conductivity, the electrical connection is made by the physical contact between the two electrodes, so the electrical properties may be degraded by the expansion and contraction of the adhesive due to heat or moisture, and the bumps and electrodes except the gold stud bump using plastic deformation of the bumps. Sensitive to the height deviation of the characteristics may be degraded by the height deviation. On the other hand, in the case of anisotropic conductivity including conductive particles, conductive particles with elasticity are included between the two electrodes, so that the conductive particles maintain electrical connection even when the adhesive is expanded and contracted, and the reliability of vision is improved because the height deviation is corrected by the conductive particles. Very good for the city.

However, in recent years, the interval between I / O is required at a level of 10 μm or less, and a short circuit phenomenon due to conductive particles in the anisotropic conductive adhesive in fine pitch has become a problem. That is, since the current commercially available conductive particles have a size of 3 to 10 μm, when the gap between I / Os is 10 μm or less, the gap between the electrodes becomes narrow during the flip chip process and the conductive particles contained in the anisotropic conductive adhesive are formed on the side of the electrode. It may be dense and two to three conductive particles may be connected to generate an electrical short. In addition, as the spacing between the I / Os becomes finer, the probability of occurrence of a short circuit by the dense conductive particles rapidly increases.

In the semiconductor packaging process, the present invention guarantees high reliability at the level of anisotropic conductive adhesives and insulation at the level of nonconductive adhesives under micropitch conditions, prevents short circuits, and connects other than adhesives such as processes using solder bumps. The present invention provides a bump electrode structure of a semiconductor device and a method of manufacturing the same, which allow a process at a low temperature while simplifying the process steps as compared to the process.

The technical objects to be achieved by the present invention are not limited to the above-mentioned technical problems.

The bump electrode structure of the semiconductor device according to the embodiment of the present invention for realizing the above object is a bump formed on the upper end of the semiconductor, at least one protruding core formed on the upper end of the bump, made of an elastic polymer material, and The bump may be formed on the top of the protruding core, and may be formed to be in contact with an electrode of another semiconductor device or a substrate.

The protruding core may be a polymeric material having thermosetting or thermoplasticity.

The polymer material may be a photosensitive polymer material.

The protruding core may be formed in a width of 1 ~ 10㎛.

The protruding core may be formed in the form of a dome or a hemisphere.

According to an aspect of the present disclosure, there is provided a method of manufacturing a bump electrode structure of a semiconductor device, the method comprising: preparing a semiconductor device in which bumps are formed, and forming a protruding core made of a polymer material on top of the bumps And forming a metal layer on top of the bump and the protruding core.

Forming the protruding core may include patterning by one of lithography, jetting, gravure offset, and imprinting.

In the forming of the protruding core, the polymer material may be heat-treated to deform into an elastic dome or hemisphere to form the protruding core.

The protruding core may be a polymer material formed on the top of the bump in a width of 1 to 10 μm.

The polymer material may be a photosensitive material.

In the forming of the metal layer, the metal layer may be formed by one of electroless plating, chemical vapor deposition (CVD), and physical vapor deposition (PVD).

In the electroless plating method, adsorbing or coating a reducing agent on an upper end of the bump and the protruding core, and electroless plating on a portion where the reducing agent on the upper end of the bump and the protruding core is adsorbed or coated to form a metal layer. It may include a step.

The reducing agent may be polydopamine formed using dopamine.

As described above, according to the bump electrode structure of the semiconductor device of the present invention, in the semiconductor packaging process, in a fine pitch condition, it guarantees high reliability of anisotropic conductive adhesive level and insulation of nonconductive adhesive level, and prevents short circuit phenomenon. It can work.

In addition, according to the bump electrode manufacturing method of the semiconductor device of the present invention configured as described above, compared to the connection process other than the adhesive, such as the process using solder bumps, the process can be made at a low temperature while simplifying the process steps There is.

1 is a conceptual diagram illustrating a bump electrode structure of a semiconductor device according to an embodiment of the present invention.
2 is a view showing a semiconductor packaging state related to the present invention.
3 is a view showing a state in which a semiconductor is packaged with an anisotropic conductive film (ACF).
4 is a view showing a state in which a semiconductor is packaged with a non-conductive film (NCF).
5 is a process diagram illustrating a process of forming a bump electrode of a semiconductor device according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Like and similar elements in the drawings are denoted by the same reference numerals wherever possible. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

1 is a view illustrating a bump electrode structure of a semiconductor device according to an embodiment of the present invention, wherein the bump electrode structure of the semiconductor device 100 includes a semiconductor 110, a bump 120, a protruding core 130, and a metal layer ( 150).

The bump electrode structure is based on the semiconductor 110 positioned on the base, and the metal pad 111 is formed on the top thereof. The passivation 115 is formed on the top of the semiconductor 110 including both sides of the metal pad 111, and a bump 120 is formed to facilitate electrical connection to the metal pad 111.

The bump 120 is a conductive material formed on top of the metal pad 111 so that the electrode and the metal pad 111 formed on the semiconductor 110 are electrically connected to each other. The bump 120 protrudes to connect the metal pad 111 and the electrode. to be.

Protruding core 130 is formed of at least one elastic polymer material formed on top of the bump 120 and spaced apart. In addition, the protruding core 130 is made of a polymer material having thermosetting or thermoplasticity. The protruding core 130 may be any polymer material having elasticity, thermosetting, or thermoplasticity as described above. Characteristically, a polymer material of an epoxy resin may be mainly used, and in detail, may be characterized by having photosensitivity.

In addition, the protruding core 130 may be printed to protrude to the upper part of the bump 120, but the protruding shape of the dome or hemispherical shape amplifies the close contact due to the elastic force of the polymer material to ensure more reliable electrical contact. Done.

In addition, the protruding core 130 is formed in a width of 1 ~ 10㎛. If the width of the protruding core 130 is less than 1 μm, the protruding width and height may be small, and thus, elasticity may not be secured, and thus reliability of the protruding core 130 may be difficult depending on physical or electrical conditions. When the width of the protruding core 130 is greater than 10 μm, securing elastic force is sufficient, but the protruding width and height are excessively large, which may cause difficulty in implementing a fine pitch.

The metal layer 150 is formed on the bump 120 and the top of the protruding core 130 to be in direct contact with the electrode 201 of the other semiconductor device or the substrate 200. The metal layer 150 may be any metal as long as the material enables the electrical connection of the semiconductor 110. Characteristically, one metal selected from Pb, Sn, Sn / Bi, Sn / Zn, Sn / Ag, Sn / Ag / Cu, and the like may be used.

In addition, the metal layer 150 may be formed by being applied to the entirety of the bump 120 and the protruding core 130 as a whole, or is formed by being limitedly applied to only a part of the bump 120 including the top of the protruding core 130. May be That is, the conductive layer is formed on the semiconductor device 100 by coating the metal layer 150 on the protruding core 130.

The metal layer 150 serves as an electrode of the semiconductor device 100. As shown in FIG. 2, the metal layer 150 is in contact with another semiconductor device or the electrode 201 of the substrate 200 to be different from the semiconductor device 100. Electrical connection is made between the device or the substrate 200.

In the connection between the semiconductor device 100 and the substrate 200, after the adhesive material A is coated on the semiconductor device 100 or the substrate 200, bumps of the semiconductor device 100 and the substrate 200 are different from each other. The 120 and the electrode 201 are positioned to correspond to each other, and the metal layer 150 is brought into close contact with the electrode 201 of another semiconductor device or the substrate 200 by applying pressure from above and below. At this time, the protruding core 130 inside the metal layer 150 is compressed to reduce the height to some extent, thereby increasing the area where the surface of the metal layer 150 is in contact with the electrode 201 of another semiconductor device or the substrate 200. Afterwards, due to the characteristics of the protruding core 130 to be restored, the degree of adhesion with the electrode 201 of another semiconductor device or the substrate 200 is increased.

Unlike the present invention, referring to the drawing of FIG. 3 in which a semiconductor is packaged using an anisotropic conductive film (ACF) as an adhesive material (A), conductive particles having elasticity in semiconductor packaging by an anisotropic conductive film (ACF) ) Is positioned between the electrodes of the semiconductor arranged vertically to electrically connect the two semiconductor devices 100 and the substrate 200, and spaced between the left and right electrodes to prevent electrical connection. However, in this case, when the gap between the left and right electrodes is narrowed, the conductive particles 300 are concentrated on the side of the electrode, and two to three conductive particles 300 are continuously aligned, which may cause unintended electrical connection. Can be.

According to the present invention, unlike FIG. 3 in which a semiconductor is packaged using an anisotropic conductive film (ACF), a fixed electrode is formed on an upper end of the bump 120 and the electrode 201 of another semiconductor device or the substrate 200 is formed. It is possible to prevent the electrodes from deviating from each other in an external physical situation, and since there are no impurities or additives between the electrodes and the electrodes, the electrical connection between the left and right electrodes can be maintained even when the distance (pitch) between the electrodes is miniaturized. It can be cut off to ensure insulation.

In addition, as shown in FIG. 4, when the semiconductor is packaged using the non-conductive film (NFC) as the adhesive material A, the semiconductor device 100 and the electrode of the substrate 200 are compared with the present invention. Without directly connecting the electrode and the electrode, the protruding core 130 is formed on the upper end of the bump 120 and the metal layer 150 is formed on the upper end of the electrode to complete the electrode 201 of another semiconductor device or substrate 200 By contacting the device, the elastic force of the polymer material at the time of contact ensures a reliable electrical connection.

5 is a process diagram illustrating a process of forming a bump electrode of a semiconductor device according to an embodiment of the present invention.

Referring to the drawings, a method of forming a bump electrode of the semiconductor device 100 is a step of preparing a semiconductor device 100 having a bump 120 (S10), the protrusion of the polymer material on the top of the bump 120 Forming a core 130 (S20), the bump 120 and the step of forming a metal layer 150 on the top of the protruding core 130 (S40). Hereinafter, in the drawings and the descriptions related to the drawings, the description of the portion filled with the auxiliary material to be etched or removed during the manufacturing process of the electrode will be omitted, and the description of the electrode structure of the semiconductor device will mainly be given.

The semiconductor device 100 is prepared by forming bumps 120 on the metal pads 111 formed on the semiconductor 110.

The formation technique of the bump 120 is a very important technique together with the formation of the under bump metallurgy (UBM) technique in the semiconductor packaging technique. The bumps 120 may be electroless Ni / Au bumps, gold stud bumps, or the like, and a conductive material protruding from the top of the metal pads 111 to electrically connect the metal pads 111 of the semiconductor device 100. It is characterized by that.

A protruding core 130 made of a polymer material is formed on the top of the bump 120. (S20) The protruding core 130 is printed by one of lithography, jetting, gravure offset, and imprinting. It is formed by patterning. That is, by selecting one of the above-described method on the top of the bump 120, the polymer material is printed and patterned to be spaced apart at regular intervals.

The spaced apart distance of the protruding core 130 may be adjusted, but the size of the protruding core 130 is formed to be 1 to 10 μm wide. This is a value for most effectively utilizing the elastic force of the protruding core 130 in the miniaturized semiconductor packaging, and if the width of the protruding core 130 is smaller than 1 μm, reliable contact between the semiconductor electrodes cannot be ensured, and the protrusion If the width of the core 130 is larger than 10 μm, the size of the semiconductor packaging cannot be reduced.

The protruding core 130 can be formed of a polymer material having thermosetting or thermoplasticity, and a photosensitive polymer material is also possible. Specifically, when the protruding core 130 is formed by lithography, only patterning with a photosensitive polymer material is possible.

In addition, in the step (S20) of forming the protruding core 130, patterning the polymer material and then heat-treating to deform the polymer material on the top of the bump 120 into an elastic dome or hemispherical solid material ( S25) may be further included. Deforming the protruding core 130 in the form of a dome or hemisphere is because it is the most efficient form to maintain a stable contact between the two electrodes.

The heat treatment may optionally be carried out only when it is necessary to modify or fix the patterned polymer material in the form of a dome or hemisphere. Specifically, jetting, gravure offset, and imprinting can be done simultaneously in the form of a dome or hemisphere while patterning the polymer material, which does not necessarily require heat treatment, but when patterning the polymer material by lithography. It is inevitable that the protruding core 130 is formed in a shape having an angle, so that the protruding core 130 having a dome or hemispherical shape must be heat treated.

The metal layer 150 is formed by one of electroless plating, chemical vapor deposition (CVD), and physical vapor deposition (PVD). (S40) The metal layer 150 includes the bump 120 and the protruding core 130. A metal material may be applied to the entire upper end of the upper part of the upper part of the upper part of the upper part of the bump 120 including the protruding core 130.

Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD) are methods of directly applying a metal material on top of the bump 120 and the protruding core 130.

The electroless plating method is a surface treatment method of chemically reducing and depositing a metal on a metal or nonmetal surface to obtain a metal film, and in the present invention, adsorbing or coating the reducing agent 140 on top of the bump 120 and the protruding core 130 ( S30), and electroless plating the portion where the reducing agent 140 is adsorbed or coated on the bump 120 and the protruding core 130 to form the metal layer 150 (S40).

The reducing agent 140 may be all of the reducing agent 140 generally used in electroless plating, and in particular, it is possible to use polydopamine formed using dopamine as a reducing agent 140. .

According to the bump electrode structure of the semiconductor device of the present invention configured as described above, in the semiconductor packaging process, in the fine pitch conditions, to ensure high reliability of the anisotropic conductive adhesive level and insulation of the non-conductive adhesive level, and prevent short circuit phenomenon It can work.

In addition, according to the manufacturing method of the bump electrode of the semiconductor device of the present invention configured as described above, compared to the connection process other than the adhesive, such as the process using solder bumps, the process can be made at a low temperature while simplifying the process steps. It works.

The bump electrode structure of the semiconductor device as described above and a method of manufacturing the same are not limited to the configuration and operation of the embodiments described above. The embodiments may be configured so that all or some of the embodiments may be selectively combined so that various modifications may be made.

100: semiconductor device 110: semiconductor
112: metal pad 115: passivation
120: bump 130: protruding core
140: reducing agent 150: metal layer
200: another semiconductor element or substrate 201: electrode
300: conductive particles
A: adhesive material

Claims (13)

Bumps formed on top of the semiconductor;
At least one protruding core formed on the bump and made of an elastic polymer material; And
And formed on the bump and the top of the protruding core, the metal layer being in contact with an electrode of another semiconductor device or a substrate.
The protruding core is formed in the shape of a dome or a hemisphere, and the protruding core is formed in a width of 1 ~ 10㎛ bump electrode structure of a semiconductor device.
The method according to claim 1,
The protruding core is a bump electrode structure of a semiconductor device which is a polymer material having thermosetting or thermoplasticity.
The method according to claim 2,
The polymer material is a bump electrode structure of a semiconductor device is a photosensitive polymer material.
delete delete Preparing a semiconductor device in which bumps are formed;
Forming a protruding core made of a polymer material on top of the bumps; And
And forming a metal layer on top of the bumps and the protruding cores.
In the step of forming the protruding core,
Heat treating the polymer material to form elastic domes or hemispheres to form protruding cores,
Forming the metal layer,
The metal layer is formed by one of electroless plating, chemical vapor deposition (CVD), and physical vapor deposition (PVD).
The electroless plating method,
Adsorbing or coating a reducing agent on top of the bump and the protruding core; And
And forming a metal layer by electroless plating a portion on which the bump and the reducing agent on the top of the protruding core are adsorbed or coated, to form a metal layer.
The method of claim 6,
Forming the protruding core,
And patterning by one of lithography, jetting, gravure offset, and imprinting.
delete The method of claim 6,
The protruding core,
Bump electrode manufacturing method of a semiconductor device which is a polymer material formed in a width of 1 ~ 10㎛ on the upper end of the bump.
The method of claim 9,
The polymer material is a photosensitive material of the bump electrode manufacturing method of a semiconductor device.
delete delete The method of claim 6,
The reducing agent is a polydopamine (polydopamine) formed using dopamine (dopamine) is a bump electrode manufacturing method of a semiconductor device.

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