JP2001237278A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device being connected with a circuit board using an anisotropic conductive member in which the number of particles being captured can be increased without sacrifice of insulation performance. SOLUTION: The semiconductor device comprises a semiconductor chip in which circuit elements are fabricated, a plurality of protruding electrodes 6 are arranged while forming gap parts and a plurality of particle guide protrusions 11 are arranged such that gap parts are located between the gap parts of the protruding electrodes 6 on the inside thereof, a circuit board 8 having a wiring layer with a plurality of circuit board electrodes 9 corresponding to the protruding electrodes 6 being formed on the surface, an insulating resin and conductive particles 2 dispersed into the insulating resin. The semiconductor device further comprises an anisotropic conductive film for bonding the semiconductor chip and the circuit board 8 by thermocompressing them thereby capturing the conductive particles 2 between the protruding electrodes 6 and the circuit board electrodes 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure of a semiconductor device, and more particularly, to a flip-chip mounting structure for connecting a semiconductor chip and a circuit board face down using an adhesive made of conductive particles and an insulating resin. It is.

[0002]

2. Description of the Related Art Flip-chip mounting, in which a semiconductor chip and a circuit board are directly connected face-down, has the advantage that the mounting area can be significantly reduced as compared with a conventional package in which a semiconductor chip is protected and molded with resin. It is a technology that is expected in the future.

[0003] Here, an anisotropic conductive film (Anisotropic Co., Ltd.) comprising conductive particles and an insulating resin is used.
A conventional flip-chip mounting technology using a negative film (hereinafter, referred to as “ACF”) will be described with reference to the drawings.

FIG. 18 is a perspective view showing a conventional flip-chip mounted semiconductor device, FIG. 19 is a cross-sectional view taken along the line BB 'of FIG. 18, and FIG. FIG. 21 is a perspective view showing a semiconductor device obtained through the manufacturing process of FIG. 20, and FIG.
23 is an explanatory diagram showing the portion B of FIG. 21 enlarged together with the flow of the conductive particles at the time of manufacturing, and FIG. 23 is an explanatory diagram showing the portion B of FIG. 21 together with the conductive particles.

The semiconductor device shown in the figure is formed by joining a protruding electrode (hereinafter referred to as a “bump”) 6 formed by a ball bonding method using a wire bonding technique and a circuit board 8 using an ACF 1. .

As shown in FIG. 19, a semiconductor chip 4 on which a predetermined circuit element is formed is provided on a main surface of the semiconductor chip 4.
A passivation film 7 as a surface protection film and a metal thin-film electrode 5 are formed.
Are formed.

The circuit board 8 on which such a semiconductor chip 4 is mounted is a multilayer circuit board in which wiring layers 8a are formed in multiple layers, and a circuit board electrode (hereinafter, referred to as a "pad") is provided on the surface thereof. 9 are formed corresponding to the bumps 6.

The ACF 1 for joining the semiconductor chip 4 and the circuit board 8 includes an insulating resin (binder) 3 and conductive particles 2 dispersed in the insulating resin 3.

Here, the metal thin-film electrode 5 is made of, for example, an aluminum thin film and has a thickness of several μm to 1 μm.
m and very thin. For this reason, the bumps 6 are formed on the metal thin-film electrodes 5 and are connected to the pads 9 of the circuit board 8 via the bumps 6 to ensure conduction.

Next, a manufacturing process of the semiconductor device having the above configuration will be described with reference to FIG.

First, as shown in FIG. 20A, a gap between a semiconductor chip 4 on which bumps 6 are formed and a circuit board 8 is set.
CF1 is provided, and the bumps 6 of the semiconductor chip 4 and the circuit board 8 are provided.
The upper pad 9 is aligned.

Next, as shown in FIG.
At the same time, the ACF 1 is heated to a predetermined temperature at which the insulating resin 3 in the resin 1 is melted and hardened, and at the same time, a predetermined pressure is applied to cause the conductive particles 2 to be captured at the joint between the bump 6 and the pad 9. Note that the conductive particles 2 exist in the ACF 1 at a predetermined density.

As a result, the space between the semiconductor chip 4 and the circuit board 8 is filled while the insulating resin 3 in the ACF 1 is melted, and the curing reaction of the insulating resin 3 is completed. Are joined. And FIG.
As shown in FIG. 1C, conduction between the semiconductor chip 4 and the circuit board 8 is obtained via the conductive particles 2.

Here, the conductive particles 2 captured between the bumps 6 and the pads 9 after the mounting (FIG. 21) contribute to the electrical connection, and thus have the desired characteristics. As the density of the conductive particles 2 present in the ACF 1 increases, the number of particles captured at the bonding site increases, but the conductive particles 2 existing near the bump 6 but not captured at the bonding site are removed from the semiconductor chip 4. When pushed out toward the outer edge of the bump 6
Then, the particles flow in the gap between the bumps 6 (FIG. 22), and the particle distribution density at this portion locally increases (FIG. 23).

The conductive particles 2 flowing into the gap between the bumps 6 cause a decrease in insulation.

[0016]

As described above, in the conventional flip-chip mounting technology using an anisotropic conductive member such as ACF, the number of trapped particles (that is, the maximum characteristic of the particle distribution density) and the insulating property are reduced. (The desired characteristic of the particle distribution density) is a trade-off.

It is an object of the present invention to provide a semiconductor device in which a semiconductor chip and a circuit board are electrically connected to each other by using an anisotropic conductive member without increasing the number of trapped particles and causing a decrease in insulation. With the goal.

[0018]

In order to solve this problem, a semiconductor device according to the present invention has a circuit element formed therein, a gap portion is formed, a plurality of projecting electrodes are arranged, and a projecting electrode is formed. A semiconductor chip in which a plurality of particle guiding protrusions are arranged such that a gap is located between the gaps of the protruding electrodes on the inside of the semiconductor chip, and a plurality of circuit boards on which a wiring layer is formed and corresponding to the protruding electrodes on the surface A circuit board on which electrodes are formed, and an insulating resin and conductive particles dispersed in the insulating resin. The semiconductor chip and the circuit board are thermocompression-bonded between the protruding electrodes and the circuit board electrodes. And an anisotropic conductive member that joins the semiconductor chip and the circuit board by capturing the conductive particles.

As a result, the conductive particles existing in the vicinity of the particle-guiding projection move outward through the gap between the particle-guiding projections, so that the particle density on the protruding electrode increases, and As the particle density decreases and the number of particles trapped between the protruding electrodes and the circuit board electrode increases, and the number of particles located between the protruding electrodes decreases, the number of trapped particles increases and the insulating property decreases. The semiconductor chip and the circuit board can be electrically connected without using the anisotropic conductive member.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a circuit element is formed, a gap is formed, a plurality of projecting electrodes are arranged, and a projecting electrode is formed inside the projecting electrode. A semiconductor chip in which a plurality of particle guiding projections are arranged such that gaps are located between gaps between electrodes, and a wiring layer is formed, and a plurality of circuit board electrodes corresponding to the projecting electrodes are formed on the surface. A circuit board, made of an insulating resin and conductive particles dispersed in the insulating resin, and conductively pressed between the semiconductor chip and the circuit board to form conductive particles between the protruding electrode and the circuit board electrode; A semiconductor device having an anisotropic conductive member that captures and joins a semiconductor chip and a circuit board, and conductive particles existing in the vicinity of the particle guiding protrusion move outward through a gap between the particle guiding protrusion. Go to the projecting electricity Particle density is high on,
As the particle density in the gap decreases, the number of particles trapped by the protruding electrodes and the circuit board electrode increases, and the number of particles located between the protruding electrodes decreases. This has the effect that it becomes possible to electrically connect the semiconductor chip and the circuit board using an anisotropic conductive member without lowering the performance.

According to a second aspect of the present invention, in the first aspect, the particle guiding projection is a semiconductor device having a columnar shape, and the particle guiding projection is substantially equal to the area of the chip electrode. Since the crown area can be obtained, the number of conductive particles guided on the protruding electrodes by the particle guiding protrusions increases, and the number of particles captured by the protruding electrodes and the circuit board electrode further increases. Has the effect that a more stable electrical connection can be obtained.

According to a third aspect of the present invention, in the second aspect, the particle guiding projection has a triangular prism shape in which one of the edge portions composed of two side faces is arranged inward. In a certain semiconductor device, since the conductive particles are smoothly guided outward by the particle guiding protrusions, the number of conductive particles guided on the protruding electrodes by the particle guiding protrusions is further increased, and more stable. It has an effect that an excellent electrical connection can be obtained.

According to a fourth aspect of the present invention, there is provided a semiconductor chip in which a circuit element is formed, a gap is formed and a plurality of protruding electrodes are arranged, a wiring layer is formed, and a protrusion is formed on the surface. A circuit board in which a plurality of circuit board electrodes corresponding to the shape electrode are formed and a particle guiding groove extending inward from the circuit board electrode is formed, and the insulating resin and the conductive particles dispersed in the insulating resin are used. A semiconductor having an anisotropic conductive member that joins the semiconductor chip and the circuit board by capturing conductive particles between the protruding electrode and the circuit board electrode by thermocompression bonding the semiconductor chip and the circuit board. The conductive particles flow outward while having a higher density through the particle guiding grooves and reach between the protruding electrodes and the circuit board electrodes. Grain caught The number is increased, an effect that it is possible to electrically connect the semiconductor chip and the circuit board using an anisotropic conductive member without causing insulation decreases with increasing the number of capture particles.

According to a fifth aspect of the present invention, there is provided a semiconductor chip in which a circuit element is formed, a gap is formed and a plurality of protruding electrodes are arranged, a wiring layer is formed, and a protrusion is formed on the surface. A circuit board on which a plurality of circuit board electrodes corresponding to the shape electrodes are formed and a particle guiding member extending inward from between the circuit board electrodes and the board electrode, and an insulating resin and dispersed in the insulating resin. Anisotropic conductive material that is made of conductive particles that are bonded by thermocompression bonding between a semiconductor chip and a circuit board, thereby capturing the conductive particles between the protruding electrodes and the circuit board electrodes and joining the semiconductor chip and the circuit board. A semiconductor device having a conductive member, wherein the conductive particles flow outward while increasing in density between the particle guide member and the particle guide member and flow between the protruding electrode and the circuit board electrode. To reach, The number of particles trapped by the raised electrode and the circuit board electrode increases, and the number of trapped particles increases, and the semiconductor chip and the circuit board are electrically connected using an anisotropic conductive member without causing a decrease in insulation. Has the effect that it becomes possible to connect to

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In these drawings, the same members are denoted by the same reference numerals, and duplicate description is omitted.

(Embodiment 1) FIG. 1 is a perspective view showing a semiconductor device according to Embodiment 1 of the present invention, and FIG.
FIG. 3 is an explanatory diagram showing an enlarged view of the portion B together with the flow of the conductive particles during manufacturing, and FIG. 3 is an explanatory diagram showing the portion B of FIG. 1 together with the conductive particles.

Since the external structure and cross-sectional structure of the semiconductor device, including the embodiment described below, are substantially the same as those shown in FIGS. 18 and 19 described in the prior art, FIG. Description is omitted.

As shown in FIG. 2, in the semiconductor device of the present embodiment, a bump having a predetermined width is formed in the outer periphery of the main surface of the semiconductor chip 4 and the bumps 6 are arranged in a line. Inside the bump 6, a bump 6 not intended for conduction, that is, a dummy bump (particle guiding projection) 1
1 are arranged in a row so that the gaps are located between the gaps of the bumps 6.

Next, a manufacturing process of a semiconductor device having such a configuration will be described with reference to FIGS.

ACF (anisotropically conductive member) 1 softens and flows in an initial stage of mounting in which a load and heat are applied,
It is extruded outward while being filled in the gap between the semiconductor chip 4 and the circuit board 8.

Then, as shown in FIG. 2, the conductive particles 2 existing in the vicinity of the dummy bumps 11 in the ACF 1 flow outward while increasing in density through the gaps of the dummy bumps 11 to form bumps 6. It reaches between the pad 9.

As a result, as shown in FIG.
The density of the distribution increases, with the particle density at the top increasing and the particle density at the gap decreasing. Therefore, the number of particles captured by the bump 6 and the pad 9 increases and the number of particles located between the bumps 6 decreases, so that
The semiconductor chip 4 and the circuit board 8 can be electrically connected by using the ACF 1 without increasing the number of trapped particles and causing a decrease in insulation.

(Second Embodiment) FIG. 4 is a sectional view showing a semiconductor chip constituting a semiconductor device according to a second embodiment of the present invention, FIG. 5 is a perspective view showing dummy bumps formed on the semiconductor chip, and FIG. FIG. 5C is an explanatory view showing the flow of the conductive particles at the time of manufacturing when the dummy bump shown in FIG. 5C is used, and FIG. 7 is an explanatory view showing the state shown in FIG. 6 after manufacturing.

The dummy bumps 11 formed on the semiconductor chip 4 can be formed in the same shape as the bumps 6 for the purpose of conduction as shown in the above-described first embodiment, but are shown in FIGS. As described above, when the bumps 6 are formed by plating, the bumps 6 may have different shapes.

That is, generally, the cross-sectional shape of the bump 6 is circular, and the vertical cross-sectional shape is a two-step projection shape as shown in FIG. On the other hand, the vertical cross-sectional shape of the dummy bump 11 can be rectangular. However, the shape of the opening of the photomask for forming the dummy bump 11 can be variously changed by changing the shape, for example, as shown in FIG.
5 (b), a columnar shape as shown in FIG. 5 (b), and a triangular prism type as shown in FIG. 5 (c).

With such a column shape, the dummy bump 11 can obtain a wide bump top area substantially equal to the area of the chip electrode 5 as compared with the bump 6. As a result, the number of conductive particles 2 induced on the bumps 6 by the dummy bumps 11 increases, so that the number of particles trapped between the bumps 6 and the pads 9 further increases, resulting in more stable electrical connection. Can be obtained.

The dummy bump 11 and the metal thin film electrode 5
Between them, a metal film (barrier metal) 13 is formed.

Here, FIG. 6 shows a main part of a semiconductor device using the triangular prism type dummy bumps 11 shown in FIG. 5C.

As shown in the figure, when the dummy bump 11 is formed in a triangular prism shape, one of the edge portions constituted by two side surfaces is formed.
It is desirable to place the two inwards.

In this way, the conductive particles 2 are smoothly guided outward by the dummy bumps 11, and as shown in FIG. 7, the number of the conductive particles 2 guided on the bumps 6 by the dummy bumps 11 is increased. , And a more stable electrical connection can be obtained.

(Embodiment 3) FIG. 8 is a perspective view showing a semiconductor device studied by the present inventor, FIG. 9A is a sectional view taken along the line AA 'of FIG. 8, and FIG. b) is B- of FIG.
FIG. 10 is a cross-sectional view taken along line B ′, FIG. 10 is an explanatory view showing an example of a resist application state in the semiconductor device of FIG. 8, and FIG. 11 is an explanatory view showing another example of a resist application state in the semiconductor device of FIG. 12 is an explanatory view showing a main part of the semiconductor device according to the third embodiment of the present invention, and FIG.
FIG. 14 is a sectional view taken along the line A ′, and FIG.
FIG. 15 is an explanatory view showing a main part of a semiconductor device as a modification of FIG.
FIG. 15 is a sectional view taken along line AA ′ of FIG.

As shown in FIG. 8, a resist (surface protective layer) 10 may be applied to the surface of the circuit board 8 except for a portion of a pad 9 connected to a bump formed on the semiconductor chip 4. .

In this case, as shown in FIG.
The pad 9 is exposed in the area where there is no 0, and the resist 1
The pad 9 is covered with the resist 10 at a portion where there is zero. Further, as shown in FIG. 10, the resist 10 is not coated around the pad 9 as shown in FIG. 10, and the resist 10 covers all parts except the pad 9 as shown in FIG. There is.

Since these structures do not control the flow of the conductive particles, the distribution density of the conductive particles is low at the joint between the bump and the pad 9, and the distribution density between the bumps and the bump is low. The phenomenon of becoming high occurs.

Therefore, as shown in FIG. 12 and FIG. 13, a particle guiding groove 12 extending inward from the pad 9 is formed by the resist 10.

As a result, as shown in FIG. 13, the conductive particles 2 flow outward while increasing in density through the particle guiding grooves 12 and reach between the bumps and the pads 9. The number of particles trapped on the semiconductor chip 4 and the circuit board 8 can be increased by using the ACF 1 without increasing the number of trapped particles and lowering the insulating property. become.

As shown in FIGS. 14 and 15,
The resist 10 may be present between the pads 9.

The particle guiding groove 12 may be formed of an insulating member other than the resist 10.

(Embodiment 4) FIG. 16 is an explanatory view showing a main part of a semiconductor device according to Embodiment 4 of the present invention.
FIG. 17 is a sectional view taken along line AA ′ of FIG.

As shown, in this embodiment, a dummy pad (particle guiding member) 16 extending inward from between the pads 9 and not intended for electrical connection is formed.

As a result, as shown in FIG. 17, the conductive particles 2 flow between the dummy pad 16 and the dummy pad 16 and move outward while increasing the density, and the space between the bump and the pad 9 is increased. To reach the bumps and pads 9
The number of particles captured by the ACF1 increases without increasing the number of captured particles and causing a decrease in insulation.
To electrically connect the semiconductor chip 4 and the circuit board 8.

In this embodiment, the flip-chip mounting using the ACF1 has been described. However, the present invention is not limited to the case where the ACF1 is used, but the anisotropic conductive paste-ACP (Anisotropic).
(Conductive Paste)-is applied to flip chip mounting for obtaining electrical connection through various anisotropic conductive members in which conductive particles are dispersed.

[0053]

As described above, according to the present invention, the particle density on the protruding electrode is increased, and the particle density in the gap is reduced, so that the particles captured by the protruding electrode and the circuit board electrode are reduced. As the number increases and the number of particles located between the protruding electrodes decreases, the number of trapped particles is increased and the semiconductor chip and the circuit board are electrically connected using an anisotropic conductive member without causing a decrease in insulation. An effective effect that it becomes possible to connect to the terminal is obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a semiconductor device according to a first embodiment of the present invention;

FIG. 2 is an explanatory diagram showing part B of FIG. 1 in an enlarged manner together with a flow of conductive particles during manufacturing.

FIG. 3 is an explanatory view showing part B of FIG. 1 in an enlarged manner together with conductive particles.

FIG. 4 is a sectional view showing a semiconductor chip included in a semiconductor device according to a second embodiment of the present invention;

FIG. 5 is a perspective view showing a dummy bump formed on a semiconductor chip;

FIG. 6 is an explanatory diagram showing a flow of conductive particles during manufacturing when the dummy bump shown in FIG. 5C is used.

FIG. 7 is an explanatory view showing a state of the portion shown in FIG. 6 after manufacturing;

FIG. 8 is a perspective view showing a semiconductor device studied by the present inventors.

9A is a sectional view taken along line A-A 'in FIG. 8; FIG. 9B is a sectional view taken along line B-B' in FIG.

FIG. 10 is an explanatory diagram showing an example of a resist application state in the semiconductor device of FIG. 8;

FIG. 11 is an explanatory diagram showing another example of the resist application state in the semiconductor device of FIG. 8;

FIG. 12 is an explanatory diagram showing a main part of a semiconductor device according to a third embodiment of the present invention;

13 is a sectional view taken along the line A-A 'in FIG.

FIG. 14 is an explanatory diagram showing a main part of a semiconductor device according to a modification of the third embodiment of the present invention;

15 is a sectional view taken along the line A-A 'in FIG.

FIG. 16 is an explanatory diagram showing a main part of a semiconductor device according to a fourth embodiment of the present invention;

FIG. 17 is a sectional view taken along the line A-A ′ in FIG. 16;

FIG. 18 is a perspective view showing a conventional flip-chip mounted semiconductor device.

19 is a sectional view taken along the line B-B 'of FIG.

FIG. 20 is an explanatory view showing the manufacturing process of the semiconductor device of FIG. 18 continuously;

FIG. 21 is a perspective view showing a semiconductor device obtained through the manufacturing process of FIG. 20;

FIG. 22 is an explanatory diagram showing part B of FIG. 21 in an enlarged manner together with the flow of conductive particles during manufacturing.

FIG. 23 is an explanatory view showing part B of FIG. 21 in an enlarged manner together with conductive particles.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Anisotropic conductive film (anisotropic conductive member, ACF) 2 Conductive particles 3 Insulating resin 4 Semiconductor chip 6 Bump (protruding electrode) 8 Circuit board 8a Wiring layer 9 Pad (circuit board electrode) 11 Dummy bump (particle) Guide protrusion) 12 Particle guide groove 16 Dummy pad (Particle guide member)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masatoshi Takeda 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F-term (reference) 5E319 AA03 AB05 AC11 BB16 CC61 5F044 KK01 KK12 LL09 QQ02

Claims (5)

[Claims] 1. A circuit element is formed, a gap is formed, a plurality of projecting electrodes are arranged, and a gap is located between the gaps of the projecting electrodes inside the projecting electrodes. A semiconductor chip on which a plurality of particle guiding protrusions are arranged as described above; a circuit board on which a wiring layer is formed and a plurality of circuit board electrodes corresponding to the protruding electrodes are formed on the surface; The semiconductor chip is made of conductive particles dispersed in a conductive resin, and the semiconductor chip and the circuit board are thermocompression-bonded to trap the conductive particles between the protruding electrodes and the circuit board electrode, thereby forming the semiconductor. A semiconductor device having an anisotropic conductive member for joining a chip and the circuit board. 2. The semiconductor device according to claim 1, wherein said particle guiding projection is formed in a column shape. 3. The semiconductor device according to claim 2, wherein the particle guiding projection has a triangular prism shape in which one of edge portions formed by two side faces is arranged inward. 4. A semiconductor chip in which circuit elements are formed, a gap portion is formed and a plurality of protruding electrodes are arranged, and a wiring layer is formed, and a plurality of circuit boards corresponding to the protruding electrodes are formed on the surface. A circuit board on which an electrode is formed and a particle guiding groove extending inward from the circuit board electrode is formed; an insulating resin and conductive particles dispersed in the insulating resin; Having an anisotropic conductive member for joining the semiconductor chip and the circuit board by capturing the conductive particles between the protruding electrode and the circuit board electrode by thermocompression bonding a substrate. Characteristic semiconductor device. 5. A semiconductor chip in which circuit elements are formed, a gap is formed and a plurality of protruding electrodes are arranged, and a wiring layer is formed, and a plurality of circuit boards corresponding to the protruding electrodes are formed on the surface. A circuit board on which an electrode is formed and a particle guiding member extending inward from between the circuit board electrode and the board electrode; and an insulating resin and conductive particles dispersed in the insulating resin. Anisotropically conducting the semiconductor chip and the circuit board by thermocompression bonding to capture the conductive particles between the protruding electrode and the circuit board electrode and joining the semiconductor chip and the circuit board. A semiconductor device comprising: a conductive member.