JP2002313990A - Semiconductor device, its manufacturing method, and mounting method of the semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device which can improve the mounting efficiency of board mounting. SOLUTION: This semiconductor device has a semiconductor chip (7), an insulation layer (8) which is formed on the main surface of the semiconductor chip (7) except regions on which a plurality of electrode pads (6) are formed, a plurality of contact pads (10) arranged on the insulation layer (8), a wiring layer (9) which is electrically connected with at least one of the plurality of electrode pads (6) and with at least one of the contact pads (10) to perform re-wiring connection, an insulating resin layer (11) which is formed on the main surface of the semiconductor chip (7) except regions on which the plurality of contact pads (10) are formed, protruding electrodes (12) formed on the plurality of contact pads (10) respectively, and an underfill material layer (13) formed on the insulating resin layer (11) so as to expose the tip parts of the protruding electrodes (12).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device, a method of manufacturing the same, and a method of mounting the semiconductor device. In particular, the present invention relates to a chip-shaped semiconductor device capable of increasing the efficiency of mounting on a wiring board, enabling high-density mounting, and realizing highly reliable board mounting, a method of manufacturing the same, and a method of mounting the semiconductor device. The present invention also relates to a semiconductor device in which electrode pads for external terminals are re-wired on a semiconductor chip and external terminals are arranged in a two-dimensional area, a method of manufacturing the same, and a method of mounting the semiconductor device.

[0002]

2. Description of the Related Art In recent years, as portable devices have become lighter and smaller and have higher densities, semiconductor packages having lead terminals as external terminals have been increasingly mounted at high density. In such a situation, a technique for mounting a chip-shaped semiconductor device on a wiring board or the like of an electronic device has been developed to achieve higher-density mounting.

A conventional semiconductor device mounted on a wiring board and a method of mounting the semiconductor device will be described below with reference to the drawings.

FIG. 9 schematically shows a cross-sectional configuration of a conventional semiconductor device. The semiconductor device shown in FIG. 9 is a chip-shaped semiconductor device used for bare chip mounting. The semiconductor device includes a semiconductor chip 1 having a semiconductor integrated circuit formed on an upper surface thereof.
An electrode pad (not shown) electrically connected to the semiconductor integrated circuit is provided, and the electrode pad (not shown) is provided.
The protruding electrode 2 is formed thereon.

The protruding electrodes 2 are formed on the periphery of the semiconductor chip 1 and constitute external terminals for electrical connection with the outside. The protruding electrodes 2 are formed of conductive metal protrusions such as bumps and solder balls. Although not shown, an insulating layer is formed on the upper surface of the semiconductor chip 1 except for the electrode pads.

Next, a conventional semiconductor device mounting method will be described with reference to FIGS. 10 (a) to 10 (c).

When a semiconductor device as shown in FIG. 9 is mounted on a wiring board, first, a wiring board 3 such as a printed board to be incorporated in an electronic device is prepared, and then, as shown in FIG. Wiring electrode 4 for connection on the upper surface side of substrate 3
And the protruding electrode 2 on the main surface side of the semiconductor chip 1 of the semiconductor device
Next, as shown in FIG. 10B,
The wiring electrodes 4 of the wiring board 3 are connected to the protruding electrodes 2 of the semiconductor device. At this time, when the protruding electrode 2 is a solder ball,
In the state where the solder balls are melted, the wiring electrodes 4 of the wiring board 3
To join.

Thereafter, as shown in FIG. 10C, in a state where the protruding electrodes 2 of the semiconductor device are connected to the wiring board 3, the gap between the semiconductor chip 1 and the wiring board 3 of the semiconductor device is filled with an insulating resin or the like. The underfill material 5 is filled and sealed.
The mounting of the substrate is completed by curing the underfill material 5.

Further, another mounting method is shown in FIGS. 11 (a) to 11 (c). This mounting method is a method in which an underfill material is supplied in advance on a wiring board, and a semiconductor device is pressed and connected so as to sandwich the underfill material. This will be further described below.

First, as shown in FIG. 11A, wiring electrodes 4 of a wiring board 3 such as a printed board to be incorporated in an electronic device.
An underfill material 5 made of an insulating resin sheet having a desired thickness and area is attached thereon.

Next, as shown in FIG. 11B, the wiring electrodes 4 of the wiring board 3 are aligned with the projecting electrodes 2 of the semiconductor device, and then the insulating resin sheet is supplied onto the wiring board 3. The semiconductor device is pressed face-down under heating and pressing conditions so as to sandwich the underfill material 5 and breaks the underfill material 5 with the protruding electrode 2, thereby connecting the protruding electrode 2 of the semiconductor chip 1 to the wiring electrode 4. To connect.

Thereafter, as shown in FIG. 11C, the sheet-like underfill material 5 is cured to complete the mounting of the substrate.

As described above, conventionally, the wiring electrodes of the wiring board and the chip-shaped semiconductor device used for bare chip mounting are connected via the protruding electrodes, and an underfill material is formed in the gap between the two to mount. In this case, the underfill material is supplied and formed before or after the connection between the two.

[0014]

In the above-mentioned conventional semiconductor device, the structure of the semiconductor device is such that a protruding electrode is provided on an electrode pad arranged around a semiconductor chip, and the electrode pad itself is not provided. Since the electrode pad is formed in a peripheral region out of the region of the semiconductor integrated circuit element, a two-dimensional area arrangement on the chip surface of the electrode pad cannot be performed. Conversion was limited.

Therefore, recently, a type in which electrode pads of a semiconductor chip are routed by wiring (rewiring), and contact pads connected to the electrode pads in a two-dimensional area on the main surface of the semiconductor chip (on the semiconductor integrated circuit element) is formed. Semiconductor devices have been developed. However, there are various restrictions in connecting such a semiconductor device (that is, a semiconductor device in which a contact pad connected to an electrode pad is formed on a semiconductor integrated circuit element region) to a wiring substrate.

For example, when a sheet-like or film-like underfill material is supplied onto a wiring board, and a bump electrode formed on a contact pad of a semiconductor device is pressed with the underfill material being sandwiched between the wiring board and the substrate, the board is mounted. Pressure is applied to the semiconductor device. For this reason, there is a problem that the semiconductor integrated circuit element region under the contact pad of the semiconductor device is damaged by the pressing force, and there is a restriction in mounting on the substrate. Further, in the case where the underfill material is filled and sealed in the gap between the wiring electrode of the wiring board and the contact pad after the connection, the problem that voids occur in the underfill material also occurs.

Furthermore, in the conventional method of mounting a semiconductor device, it is necessary to fill or attach an underfill material to the wiring substrate for each semiconductor device, and mount the substrate. There is also a problem from the viewpoint of implementation efficiency of implementation. In addition, there is also a problem that mounting cost is increased by newly introducing high-precision mounting equipment used for mounting the substrate.

The present invention has been made in view of the above points, and a main object of the present invention is to provide a semiconductor device and a mounting method capable of improving the mounting efficiency of mounting on a substrate. It is another object of the present invention to provide a semiconductor device capable of realizing substrate mounting with excellent reliability, a method of manufacturing the same, and a method of mounting the semiconductor device.

[0019]

A semiconductor device according to the present invention includes a semiconductor chip having a main surface provided with a plurality of electrode pads, and a semiconductor chip having a main surface excluding the plurality of electrode pads on the main surface of the semiconductor chip. The formed insulating layer, a plurality of contact pads arranged in a region within the main surface of the semiconductor chip and on the insulating layer, and electrically connected to at least one of the plurality of electrode pads, and A wiring layer electrically connected to at least one of the contact pads and thereby performing rewiring connection, and an insulating resin formed in a region excluding the plurality of contact pads and on a region in the main surface of the semiconductor chip Layer, a protruding electrode provided on each of the plurality of contact pads, and an underfill material provided on the insulating resin layer, exposing a top of the protruding electrode. Provided with a door.

Another semiconductor device according to the present invention provides a semiconductor chip having a main surface on which a plurality of electrode pads are provided, and an elastic chip formed on a region of the main surface of the semiconductor chip other than the plurality of electrode pads. A body layer, a plurality of contact pads two-dimensionally arranged in a region within the main surface of the semiconductor chip and on the elastic body layer, and electrically connected to at least one of the plurality of electrode pads; A wiring layer electrically connected to at least one of the plurality of contact pads and thereby performing rewiring connection, and formed on a region excluding the plurality of contact pads and on a region within a main surface of the semiconductor chip; An insulating resin layer, a protruding electrode provided on each of the plurality of contact pads, and an underfill provided on the insulating resin layer by exposing a top portion of the protruding electrode. And a wood layer.

In one embodiment, an upper surface of the underfill material layer is substantially flush with a top of the bump electrode.

In one embodiment, the top of the bump electrode is 1 μm to 1 μm from the top surface of the underfill material layer.
The projection is exposed at 200 [μm].

In one embodiment, the protruding electrode is
It is a solder ball.

It is preferable that the protruding electrode is a solder ball, and the underfill material layer is made of a thermoplastic resin.

The elastic layer has a Young's modulus of 10 to 200.
It is preferably in the range of 0 [kg / mm ² ].

In one embodiment, the underfill material layer is an epoxy resin layer.

It is preferable that an end of the elastic layer has a hypotenuse in a cross-sectional shape.

According to the method of manufacturing a semiconductor device of the present invention, there is provided a step of preparing a semiconductor chip having a main surface on which a plurality of electrode pads are formed, and a method of forming a semiconductor chip on an area of the main surface excluding the plurality of electrode pads. Forming an elastic layer made of a low elastic material, connecting one end to at least one of the plurality of electrode pads, and extending the other end onto the elastic layer. Forming a wiring layer having a configuration of two-dimensionally disposing the wiring layer, and covering at least the wiring layer and the electrode pads on a region in the main surface of the semiconductor chip except for the plurality of contact pads. A step of forming an insulating resin layer; a step of forming a bump electrode made of a conductive material on the contact pad; and a step of forming a bump electrode on a region in the main surface of the semiconductor chip. Including exposing the top of the electrode, and forming the underfill material layer.

It is preferable that the step of preparing the semiconductor chip is a step of preparing a semiconductor wafer having a plurality of semiconductor chips formed on the surface thereof.

A method of mounting a semiconductor device according to the present invention includes a semiconductor chip having a main surface provided with a plurality of electrode pads; and a semiconductor chip formed on a region of the main surface of the semiconductor chip excluding the plurality of electrode pads. An elastic body layer; a plurality of contact pads two-dimensionally arranged in a region within the main surface of the semiconductor chip and on the elastic body layer; and electrically connected to at least one of the plurality of electrode pads. A wiring layer that is at least electrically connected to the plurality of contact pads and thereby performs rewiring connection; and an insulating layer formed in a region excluding the plurality of contact pads and on a region in a main surface of the semiconductor chip. A projecting electrode provided on each of the plurality of contact pads; and an underfill provided on the insulating resin layer to expose a top of the projecting electrode. A semiconductor device comprising: a material layer; and electrically mounting the semiconductor device on a wiring board having wiring electrodes, and mounting the semiconductor device on the main surface side of the semiconductor device and the main surface of the wiring board. A step of positioning the protruding electrode of the semiconductor device and the wiring electrode of the wiring substrate so that the protruding electrode of the semiconductor device faces the surface side, and contacting the protruding electrode of the semiconductor device with the wiring electrode of the wiring substrate. And a step of softening and melting the underfill material layer of the semiconductor device by heating and filling and sealing a gap between a main surface of the semiconductor device and a main surface of the wiring board with the underfill material layer. I do.

In one embodiment, the step of contacting the projecting electrode of the semiconductor device with the wiring electrode of the wiring board includes the step of contacting the top of the projecting electrode exposed from the underfill material layer with the wiring of the wiring board. This is carried out by pressing the electrode to make it bite into contact with the electrode.

In one embodiment, a top of the protruding electrode of the semiconductor device is protruded and exposed from an upper surface of the underfill material layer, and the protruding electrode is a solder ball. The layer is made of a thermoplastic resin, and further, a step of applying a solder paste having a melting point lower than the melting point of the solder balls on the wiring electrodes of the wiring board,
A step of melting the applied solder paste at a temperature lower than the melting point of the solder ball after contacting the projecting electrode with the wiring electrode.

[0033]

Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numeral for simplification of description. Note that the present invention is not limited to the following embodiments.

First, a semiconductor device according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 schematically shows a configuration of a chip-shaped electrode rewiring type semiconductor device which is a prerequisite structure of the semiconductor device of the present embodiment. FIG. 1A is a perspective view, partially cut away to make the structure easier to see. In FIG. 1A, some components are hatched for visual convenience. FIG. 1B is a diagram showing the IB-I in FIG.
It is sectional drawing which followed the B 'line.

As shown in FIGS. 1A and 1B, the prerequisite structure of the semiconductor device according to this embodiment includes a semiconductor chip 7 having a main surface provided with a plurality of electrode pads 6;
An elastic layer 8 is formed on a region of the main surface of the semiconductor chip 7 other than the electrode pads 6. A plurality of contact pads 10 are two-dimensionally arranged in a region within the main surface of the semiconductor chip 7 and on the elastic layer 8, and at least one of the plurality of electrode pads 6 and the plurality of contact pads The wiring layer 9 is connected to at least one of the wirings 10 again. In the present embodiment, one contact pad 10 is connected via one wiring layer 9 to one contact pad 10.
Connected to one electrode pad 6. Further, the contact pad 10 and the wiring layer 9 are formed integrally. An insulating resin layer 11 is formed on a region excluding the contact pad 10 and on a region within the main surface of the semiconductor chip 7,
On each contact pad 10, a protruding electrode (solder ball) 12 is provided.

The structure shown in FIGS. 1A and 1B will be described below in detail. The structure shown in FIG. 1 includes a semiconductor chip 7 having a plurality of electrode pads 6 connected to an internal semiconductor integrated circuit element in a peripheral region on one main surface, and a main surface region of the semiconductor chip 7 excluding each electrode pad 6. And an elastic layer 8 made of a low elastic resin formed thereon. The elastic layer 8 formed in the main surface of the semiconductor chip 7 has a metal layer connected to each electrode pad 6. A plurality of contact pads 10 two-dimensionally arranged by being re-wired and connected by a wiring layer 9 made of a conductor are provided. An insulating resin layer 11 such as a solder resist for protecting the electrode pads 6 and the wiring layer 9 is formed on the main surface of the semiconductor chip 7 except for the contact pads 10, and on each contact pad 10, Protruding electrodes 1 such as solder balls
2 are provided. All contact pads 1
It is not always necessary to provide the protruding electrodes (solder balls) 12 on the 0, and the number and pitch of the protruding electrodes 12 may be set in accordance with the wiring electrodes of the wiring board.

As shown in FIG. 2A, the semiconductor device of this embodiment has an underfill material layer 13 in addition to the configuration shown in FIG. The underfill material layer 13 is formed on the insulating resin layer 1 so that the top of the bump electrode 12 is exposed.
1 is formed. Unlike the conventional configuration shown in FIG. 9, the semiconductor device according to the present embodiment has a contact pad 10
The top of the upper protruding electrode 12 is exposed, and the insulating resin layer 11 is exposed.
It has a configuration having an underfill material layer 13 provided thereon. The underfill material layer 13 is formed of, for example, an epoxy resin. Other than the epoxy resin, any other material that can be hermetically sealed when mounted on a substrate and has an insulating property can be used. It can be used as a material.

In FIG. 2A, the underfill material layer 13 is formed.
The upper surface of the bump electrode 12 is substantially flush with the top of the bump electrode 12, but depending on the mounting method at the time of mounting on the substrate, the top of the bump electrode 12 may be
A configuration may be employed in which the projections 3 project from the upper surface of 3 to 1 μm to 200 μm, preferably about 50 μm, and are exposed. Further, as shown in FIG.
May be made thicker. More specifically, the underfill material layer 13 located outside of the outermost contact pad of the contact pad 10 may be configured so that its upper surface is higher than the top of the bump electrode 12. Good. When the film thickness is adjusted so that the upper surface of the underfill material layer 13 is higher than the top of the protruding electrode 12, when the substrate is mounted, the gap between the wiring substrate and the semiconductor device is hermetically sealed. A fillet portion made of an underfill material can be formed, thereby improving mounting reliability. 2A and 2B, the solder balls are used as the protruding electrodes 12. However, the present invention is not limited to this, and bump-shaped protruding electrodes made of a metal material may be used.

The elastic modulus (Young's modulus) of the elastic layer 8 is 10
It is preferably in the range of ~2000 [kg / mm ^2], further more preferably in the range of 10~1000 [kg / mm ^2]. The coefficient of linear expansion of the elastic layer 8 is preferably in the range of 5 to 200 [ppm / ° C.], and more preferably in the range of 10 to 100 [ppm / ° C.]. The elastic layer 8 may be made of, for example, a polymer such as an ester-bonded polyimide or an acrylate-based epoxy, and may be made of any suitable material as long as it has a low elastic modulus and shows insulation. The thickness of the elastic layer 8 is, for example, 1 to 100 [μm], and preferably 30 [μm].

As shown in FIGS. 1 and 2, the elastic layer 8
Is preferably configured to have a hypotenuse in the cross-sectional shape. With such a configuration, it is possible to improve the formation accuracy of the wiring layer 9 used for routing the electrode pads 6 and prevent disconnection, and as a result, it is possible to increase the reliability. In the present embodiment,
The elastic layer 8 is formed of an elastic resin, but may be, for example, 5 [μm] depending on the mounting method when mounting the substrate.
It may be formed from an insulating layer such as polyimide having a thickness greater than or equal to the thickness.

Next, a method for manufacturing a semiconductor device according to the present embodiment will be described with reference to FIGS. 3A to 4B. FIGS. 3A to 4B are process cross-sectional views showing main processes for describing the manufacturing method of the present embodiment.

First, as shown in FIG. 3A, a plurality of electrode pads 6 are formed in a peripheral portion on one main surface, and a semiconductor chip 7 on which a semiconductor integrated circuit element is formed is prepared. Instead of a chip unit, a semiconductor wafer in which a plurality of semiconductor chips are formed in the plane may be prepared and manufactured at a wafer level. In that case, the production at a mass production level becomes possible, and the merit in the production process is great.

Next, as shown in FIG. 3B, a main surface area on the main surface of the prepared semiconductor chip 7 or each semiconductor chip in the semiconductor wafer, excluding a plurality of peripheral electrode pads 6. The elastic layer 8 is formed by depositing a low elastic material so as to cover the elastic layer.

Specifically, first, a photosensitive insulating low-elastic material is coated on the electrode pad 6 and the passivation film (not shown) formed on the main surface of the semiconductor chip 7 by 100 [m]. [mu] m] and dried to form an elastic layer film. Exposure and development are sequentially performed on the dried elastic layer film to form the elastic layer 8 in which the portion of the electrode pad 6 of the semiconductor chip 7 is opened. In this case, for example, scattered light is used instead of parallel light in the exposure, and the elastic layer 8 in the opening is used.
Is not perpendicular to the main surface of the semiconductor chip 7 and has an oblique side without an acute angle portion. That is, the elastic layer 8 is formed such that the angle formed by the upper surface (main surface) and the slope forms an obtuse angle (for example, about 100 to 140 degrees). In the present embodiment, since the end of the opening of the elastic layer 8 is formed so as to be smoothly connected to the surface of the semiconductor chip 7, the wiring layer 9 is easily formed and a structure that is hard to be disconnected is manufactured. can do.

From the viewpoint of reducing the thermal stress when the semiconductor device is mounted on the substrate, the thickness of the elastic layer 8 is preferably as large as possible without impairing the process after coating.
It may be about 0 [μm] or about 1 [mm]. Further, as the low elastic material having photosensitivity, for example, a polymer such as an ester bond type polyimide or an acrylate-based epoxy may be used, as long as it has a low elastic modulus and an insulating property. Further, the photosensitive low elasticity material does not need to be formed by drying a liquid material, and a material formed in a film shape in advance may be used. In that case, an opening can be formed in the low-elasticity material by bonding a film-like low-elasticity material on the semiconductor chip 7, exposing and developing, thereby exposing the electrode pads 6 on the semiconductor chip 7. be able to. Further, it is not necessary that the insulating low-elastic material forming the elastic layer 8 has photosensitivity. When a non-photosensitive material is used, the electrode pads 6 on the semiconductor chip 7 can be exposed by mechanical processing using laser or plasma or chemical processing such as etching.

Next, as shown in FIG. 3C, on the main surface of the semiconductor chip 7, one end is connected to the electrode pad 6, the other end is extended on the elastic layer 8, and the two-dimensional arrangement is performed. To form the wiring layer 9 constituting the contact pad 10.

More specifically, first, the thickness of the main surface of the semiconductor chip 7 is, for example, 0.2 [μm] by a vacuum evaporation method, a sputtering method, a CVD method, or an electroless plating method.
A titanium (Ti) film having a thickness of about 0.5 μm and a thin metal layer formed of a copper (Cu) film having a thickness of about 0.5 μm formed thereon are formed. Then, a negative photosensitive resist is applied on the thin metal layer, and a portion other than a desired pattern portion of the finished product is cured, and a reaction portion is removed to form a plating resist film. Here, a negative photosensitive resist is used when forming the plating resist film, but it goes without saying that a positive photosensitive resist may be used. Next, a thick metal layer made of, for example, a Cu film is selectively formed to a thickness of, for example, about 20 [μm] on the thin film metal layer other than the portion where the plating resist film is formed by an electrolytic plating method.

After the formation of the thick metal layer, the plating resist film is melted and removed. Next, an etching solution capable of melting the thin film metal layer and the thick film metal layer, such as a cupric chloride solution for a Cu film and an EDTA solution for a Ti film, gives a thick film. The thin-film metal layer having a smaller thickness than the metal layer is removed first. By this step, the electrode pad 6 and the wiring layer 9 are formed on the main surface of the semiconductor chip 7.
And a predetermined metal wiring pattern including the contact pads 10 can be formed.

Although Cu was used as a material for forming the thin film metal layer or the thick film metal layer, Cr, W,
Ti / Cu, Ni or the like may be used. Alternatively, the thin-film metal layer and the thick-film metal layer may be made of different metal materials, and an etchant that selectively etches only the thin-film metal layer may be used in a final etching step.

Next, as shown in FIG. 3D, on the main surface of the semiconductor chip 7, at least the wiring layer 9 and the electrode pads 6 except for the contact pads 10 are covered with an insulating resin to thereby provide an insulating material. The conductive resin layer 11 is formed.

More specifically, after a photosensitive solder resist (insulating resin) is applied on the elastic layer 8, the solder pad is exposed using photolithography so that only the contact pads 10 are exposed. A resist film (insulating resin layer 11) is formed. This solder resist film protects the electrode pad 6 and the wiring layer 9 other than the contact pad 10 from molten solder during mounting.

Next, as shown in FIG. 4A, a bump electrode 12 is formed on the contact pad 10 on the semiconductor chip 7 by using a conductive material. Specifically, a metal ball made of solder, solder-plated copper, nickel, or the like is placed on the contact pad 10, and the metal ball and the contact pad 10 are melt-bonded to form the protruding electrode 12.

Thereafter, as shown in FIG. 4B, an underfill material layer 13 is formed on the main surface of the semiconductor chip 7 so as to expose the tops of the projecting electrodes 12 on the contact pads 10. In the present embodiment, the underfill material layer 13 is formed such that the upper surface of the underfill material layer 13 is substantially flush with the top of the bump electrode 12. The top is 1 [μm] to 200 [μm] from the upper surface of the underfill material layer 13.
m], preferably 50 [μm]. An underfill material layer 13 is formed on the top of the bump electrode 12.
By projecting from the surface, during mounting on the board, the protruding electrode can bite into the wiring electrode of the wiring board by pressing, and the underfill material layer 13 can be brought into close contact with the wiring board side. Can be improved.

Further, as shown in FIG. 2B, the underfill material layer 13 located at the peripheral portion of the semiconductor chip 7 is formed.
The underfill material layer 13 may be formed so that the height of the underfill material 13 is increased. More specifically, the upper surface of the underfill material layer 13 located outside the outermost contact pad of the contact pads 10 is formed on the protruding electrode 12.
Adjust the thickness so that it is above the top of the
An underfill material layer 13 may be formed. In this way, when mounted on a board, the gap between the wiring board and the semiconductor device can be hermetically sealed, and a fillet portion made of an underfill material can be formed. As a result, mounting reliability can be improved.

Specifically, after an underfill material is applied on the insulating resin layer 11 on the semiconductor chip 7, the top of the contact pad 10 is exposed using photolithography and etching techniques. An underfill material layer 13 is formed. Here, an epoxy resin is used as a material of the underfill material layer.

Through the steps described above, a chip-shaped high-density semiconductor device suitable for mounting on a substrate can be realized.

As described above, in the present embodiment, the manufacturing process using the semiconductor chip has been described. However, the step of preparing the semiconductor chip having the electrode pads formed on the main surface includes the step of preparing the semiconductor chip within the surface. A plurality of semiconductor wafers may be prepared and manufactured in units of semiconductor wafers. Thus, since the elastic layers and the wiring layers in a large number of semiconductor chip regions are formed without changing the semiconductor wafer before being divided into the semiconductor chips, the manufacturing cost can be significantly reduced.

Next, a method for mounting the semiconductor device according to the present embodiment will be described with reference to FIGS. FIGS. 5A to 5C are process cross-sectional views showing main processes for describing a method of mounting the semiconductor device according to the present embodiment.

First, as shown in FIG.
The main surface side of the semiconductor device of the present embodiment shown in (a) and the wiring electrode surface side of the wiring substrate 15 having the wiring electrodes 14 are opposed to each other, and the electrodes are aligned. As described above, the semiconductor device of the present embodiment is a semiconductor device including the underfill material layer 13. More specifically, the semiconductor device includes a semiconductor chip 7 having a plurality of electrode pads 6 on a main surface and an electrode pad 7. The elastic layer 8 formed on the main surface of the semiconductor chip 7 excluding 6 and the wiring layer 9 connected to each electrode pad 6 on the elastic layer 8 within the main surface of the semiconductor chip 7 in a rewiring arrangement. A plurality of contact pads 10 arranged two-dimensionally, an insulating resin layer 11 formed on the main surface of the semiconductor chip 7 excluding the plurality of contact pads 10, and a bump electrode 12 provided on each of the contact pads 10; , Projecting electrode 12
And an underfill material layer 13 provided on the insulating resin layer 11 by exposing a top portion of the semiconductor device.

Next, as shown in FIG. 5B, the protruding electrodes 12 of the semiconductor device are brought into contact with the wiring electrodes 14 of the wiring board 15. Here, a more reliable connection can be obtained by pressing the top of the protruding electrode 12 exposed from the underfill material layer 13 against the wiring electrode 14 of the wiring board 15 so as to make it abut.

Thereafter, as shown in FIG. 5C, the underfill material layer 13 of the semiconductor device is softened and melted by heating, and the gap between the main surface of the semiconductor device and the main surface of the wiring board 15 is reduced. Filling and sealing with 13 completes the mounting of the substrate. As the heating condition, the underfill material layer 13 is softened and melted by heating at 150 ° C., and the gap can be filled without voids.

According to the semiconductor device mounting method of the present embodiment, the semiconductor device having the underfill material layer 13 is brought into contact with the wiring electrode 14 of the wiring board 15 and then the underfill material layer 13 is subjected to heat treatment. In addition, electrical connection and sealing between electrodes can be performed, and highly efficient and highly reliable substrate mounting can be realized.

As described above, according to the semiconductor device of this embodiment, since the semiconductor device has the underfill material layer 13 required for mounting the substrate, it is more efficient,
A highly reliable board mounting can be realized. Further, since the protruding electrodes 12 such as solder balls are provided on the contact pads 10 connected to the wiring layer 9, a structure for mounting the semiconductor device on the wiring board can be performed extremely easily and quickly. I have. In the semiconductor device of the present embodiment, since the elastic layer 8 is interposed between the protruding electrode 12 to be connected and the semiconductor integrated circuit element region of the semiconductor chip 7, the element is pressed by the pressing force during mounting. It has a structure that prevents breakage and, as a result, can be efficiently mounted.

Further, since the wiring layer 9 is provided on the elastic layer 8 serving as a base, when the semiconductor device is mounted on a wiring board such as a printed board, the heating and cooling of the semiconductor device may be accompanied. Even if stress such as thermal stress is applied to the wiring layer 9, the stress applied to the wiring layer 9 is reduced. Therefore,
Disconnection of the wiring layer 9 at the time of mounting on a substrate or the like can be prevented, and a highly reliable wiring structure can be realized. Further, the elastic layer 8 has an advantage that thermal stress generated from the solder ball 12 having a large heat capacity can be absorbed.

In addition, since the contact pads 10 serving as external terminals are two-dimensionally arranged on the main surface of the semiconductor device, it is possible to provide a large number of external terminals in a small area and to form a pattern. The structure is such that the electrode pad 6 and the contact pad 10 can be connected by a simple wiring layer 9. Therefore, a semiconductor device which is a small and thin semiconductor device and can cope with an increase in the number of pins is realized. Moreover, it has a structure suitable for fine processing and capable of responding to increase in the number of pins.

In the semiconductor device of the present embodiment, when the height of the underfill material layer 13 is smaller than the height of the ball electrode 12, there is also an advantage that the self-alignment of the semiconductor device with respect to the wiring board 15 can be improved. can get. Self-alignment refers to wiring board 15
Wiring electrode 14 and the ball electrode 12 of the semiconductor device
Automatic alignment (alignment) without regulation of external force. If self-alignment is good, connection reliability and yield are improved, and semiconductor devices with excellent reliability can be manufactured efficiently. It is possible to do. Hereinafter, further description will be made with reference to FIGS. 6, 7 and 8.

As shown in FIG. 6, the semiconductor device according to the present embodiment having excellent self-alignment property has a configuration in which the height of the ball electrode 12 is made larger than that of the underfill material layer 13 so that the ball electrode 12 made of a solder ball is formed. The underfill layer 13 has a configuration in which the top protrudes from the upper surface of the underfill material layer 13 and is exposed, and the underfill layer 13 is made of a thermoplastic resin. Note that components other than the semiconductor chip 7, the ball electrode 12, and the underfill layer 13 are omitted in FIG.

Wiring board 15 on which this semiconductor device is mounted
A solder paste 20 having a softening point of the thermoplastic resin forming the underfill material layer 13 and a melting point lower than the melting point of the ball electrode 12 is applied on the wiring electrode (land) 14. The wiring electrode 1 of the wiring board 15
It is preferable that a solder resist 21 is formed on portions other than the portion where 4 is located, as shown in FIG.

Explaining the configuration of the semiconductor device shown in FIG. 6 as an example, the diameter of the ball electrode 12 is 0.3 to 0.3.
5 mm, and the pitch of the ball electrodes 12 is 0.5 mm
It is. The pitch of the wiring electrodes 14 of the wiring board 15 is also matched with the pitch of the ball electrodes 12. The number of the ball electrodes 12 is, for example, 4 to 400, and the thickness of the underfill material layer 13 is 0.15 to 0.25 mm.

As shown in FIG. 6, after the ball electrode 12 of the semiconductor device is aligned with the wiring electrode 14 of the wiring board 15, the ball electrode 12 and the wiring electrode 14 are brought into contact with each other.
Next, a reflow process is performed. FIG. 8 shows a reflow profile of the reflow step. The horizontal axis in FIG. 8 is time,
The vertical axis represents temperature. RT, T1, T2, T3 are
The room temperature, the resin softening point of the underfill material layer 13, the melting point of the solder paste, and the melting point of the ball electrode are shown, respectively, and S1, S2, and S3 represent the self-alignment step, the ball electrode melting step, and the cooling step, respectively. Is shown.

First, as a premise, when the ball electrode 12 and the wiring electrode 14 are brought into contact with each other, depending on the accuracy of the mounting device, as shown in FIG. A mounting displacement (S) may occur in between.

Next, in the self-alignment step S1,
When the solder paste 20 is melted, as shown in FIG. 7B, the solder paste 20 is self-aligned, that is, both are positioned at a desired position C due to the surface tension of the melted solder paste 20.

In the present embodiment, the melting point of the solder paste 20 is, for example, 150 ° C. to 200 ° C., and as shown in FIG.
Further, the treatment is performed at a temperature lower than the melting point of the ball electrode 12. The melting point of the ball electrode 12 is, for example, 220 ° C. to 25 ° C.
0 ° C. The softening point of the thermoplastic resin constituting the underfill material layer 13 is 80 to 120 ° C., and this resin has a property of not being carbonized and thermoset at the melting point of the ball electrode.

In the structure of the present embodiment, the height of the underfill material layer 13 is made smaller than the height of the ball electrode 12 so that the ball electrode 12 protrudes from the underfill material layer 13. In the above, self-alignment can be effectively realized. That is, the portion of the ball electrode 12 protruding from the underfill material layer 13 moves in the direction of the molten solder paste, thereby realizing self-alignment. By setting the temperature lower than the melting point of the ball electrode 12 and higher than the melting point of the solder paste 20, the portion of the ball electrode 12 protruding from the underfill material layer 13 is not melted, and And self-alignment can be effectively realized.

Next, in the ball electrode melting step S2,
As shown in FIG. 7C, the ball electrode 12 is melted,
Then, the semiconductor device (semiconductor chip 7) is connected to the wiring board 15.
To bring the underfill material layer 13 and the solder resist 21 into contact with each other. Thereafter, in the cooling step S3, the temperature is lowered to about room temperature, and the underfill material layer 1
When 3 is cured, the underfill adhesion is completed.
In this way, while obtaining the self-alignment effect,
The underfill material can be efficiently formed on the mounting body including the semiconductor device and the wiring board 15.

In this embodiment, the underfill material layer 13
Is composed of a thermoplastic resin for the following reason. If the underfill material layer 13 is made of a thermosetting resin, it is carbonized and hardened at the temperature of the melting point of the ball electrode 12, and as a result, the underfill material layer 13 serving to support the ball electrode 12 is formed. Will be less reliable. Further, since the resin has been cured at the stage shown in FIG. 7C, when the thickness of the underfill material layer 13 is small when the semiconductor device (semiconductor chip 7) is pressed against the wiring board 15, In some cases, contact failure between the ball electrode 12 and the wiring electrode 14 may occur. On the other hand, when the underfill material layer 13 is made of a thermoplastic resin as in this embodiment,
The semiconductor device (semiconductor chip 7) can be pressed against the wiring board 15 in a state where the resin (underfill resin) constituting the semiconductor device is soft, so that the thickness of the underfill material layer 13 is reduced, and the ball electrode 12 and the wiring electrode 14 can be securely connected.

As described above, in the semiconductor device of this embodiment, since the contact pads 10 connected to the wiring layer 9 are formed on the elastic layer 8, the semiconductor device is mounted on the wiring board 15 such as a mother board. Later, the stress applied to the connection part due to the difference in thermal expansion coefficient between the wiring board 15 and the semiconductor device can be absorbed by the elasticity of the elastic layer 8, that is,
In addition to the configuration that can realize a semiconductor device with a high stress relaxation function, it also has an underfill material required when mounting the board, so that a more efficient and highly reliable board mounting can be realized. It has become. More specifically, the semiconductor device of the present embodiment has a structure that can be formed in a semiconductor wafer shape, is a small and thin semiconductor device. Therefore, the semiconductor device is suitable for fine processing and can cope with increase in the number of pins. Further, since the wiring layer 9 integrated with the external electrode (10) is formed on the elastic layer 8 as a base, disconnection of the wiring layer 9 can be prevented, and thermal stress of the external electrode can be buffered. In addition, the reliability of bonding at the time of mounting on a substrate can be improved. Most of all, since it has the underfill material 13 required for mounting on the substrate, it has a structure that can realize more efficient and highly reliable mounting on the substrate.

Further, according to the method of manufacturing a semiconductor device of the present embodiment, a chip-shaped high-density semiconductor device suitable for mounting on a substrate can be manufactured. The manufacturing method is a manufacturing method that can efficiently realize a chip-shaped high-density type semiconductor device suitable for mounting on a board, and is compatible with a mass production level. Furthermore, the method for mounting a semiconductor device according to the present embodiment provides a highly efficient and highly reliable semiconductor device having the underfill material layer 13 by contacting the semiconductor device with the wiring electrode 14 of the wiring board 15 and heating the underfill material. A highly flexible substrate mounting can be realized.

Although the preferred embodiment of the present invention has been described above, such description is not restrictive and, of course, various modifications are possible.

[0081]

According to the present invention, the underfill material layer for exposing the top of the bump electrode is formed on the insulating resin layer, so that the mounting efficiency of the substrate mounting can be improved. In addition, a semiconductor device having an underfill material layer is brought into contact with a wiring electrode of a wiring board and the underfill material is subjected to a heat treatment, so that highly efficient and highly reliable board mounting can be realized.

In the method of manufacturing a semiconductor device according to the present invention, an elastic layer, a wiring layer, and an underfill material layer in a large number of semiconductor chip regions are formed in a state of a semiconductor wafer before being divided into semiconductor chips. So you can
When semiconductor chips used for manufacturing are prepared in a state of a semiconductor wafer, manufacturing costs can be significantly reduced. In addition, in the case where the protruding electrode of the semiconductor device is a solder ball, and the top is made to project from the upper surface of the constituent underfill material layer from the thermoplastic resin and is exposed, the melting point is lower than the melting point of the solder ball. The self-alignment function can be effectively performed by applying a solder paste having a shape on the wiring electrode of the wiring board, and then bringing the bump electrode into contact with the wiring electrode, and then melting the solder paste at a temperature lower than the melting point of the solder ball. Can be demonstrated.

[Brief description of the drawings]

FIG. 1A is a perspective view schematically showing a prerequisite structure of a semiconductor device according to an embodiment of the present invention, and FIG.
It is sectional drawing along the IB-IB 'line in (a).

FIG. 2A is a cross-sectional view schematically illustrating a configuration of a semiconductor device according to an embodiment of the present invention, and FIG. 2B is a cross-sectional view illustrating a modified example of the semiconductor device according to the embodiment of the present invention. It is sectional drawing which shows typically.

FIGS. 3A to 3D are process cross-sectional views illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIGS. 4A and 4B are process cross-sectional views illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIGS. 5A to 5C are process cross-sectional views illustrating a method for mounting a semiconductor device according to an embodiment of the present invention.

FIG. 6 is a cross-sectional view illustrating a configuration of a semiconductor device and a wiring board according to the embodiment of the present invention.

FIGS. 7A to 7D are process cross-sectional views for explaining a self-alignment function.

FIG. 8 is a graph showing a reflow profile of a reflow step.

FIG. 9 is a cross-sectional view schematically showing a configuration of a conventional semiconductor device.

FIG. 10 is a process sectional view showing a conventional method for mounting a semiconductor device.

FIG. 11 is a process sectional view showing another mounting method of the conventional semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor chip 2 Protruding electrode 3 Wiring board 4 Wiring electrode 5 Underfill material 6 Electrode pad 7 Semiconductor chip 8 Elastic layer 9 Wiring layer 10 Contact pad 11 Insulating resin layer 12 Protruding electrode 13 Underfill material layer 14 Wiring electrode 15 Wiring Substrate 16 Underfill sheet 20 Solder paste 21 Solder resist

Claims (14)

[Claims] A semiconductor chip having a main surface provided with a plurality of electrode pads; an insulating layer formed on a region of the main surface of the semiconductor chip other than the plurality of electrode pads; A plurality of contact pads arranged in a region within the main surface and on the insulating layer; electrically connected to at least one of the plurality of electrode pads; and electrically connected to at least one of the plurality of contact pads. A wiring layer that performs rewiring connection thereby; an insulating resin layer formed in a region excluding the plurality of contact pads and on a region in the main surface of the semiconductor chip; A semiconductor device comprising: a provided protruding electrode; and an underfill material layer provided on the insulating resin layer, exposing a top of the protruding electrode. 2. A semiconductor chip having a main surface on which a plurality of electrode pads are provided; an elastic layer formed on a region of the main surface of the semiconductor chip other than the plurality of electrode pads; A plurality of contact pads two-dimensionally arranged in a region within the main surface of the elastic layer and at least one of the plurality of contact pads electrically connected to at least one of the plurality of electrode pads A wiring layer electrically connected to one and thereby performing rewiring connection; and an insulating resin layer formed on a region excluding the plurality of contact pads and on a region within the main surface of the semiconductor chip; A semiconductor device comprising: a protruding electrode provided on each of the plurality of contact pads; and an underfill material layer provided on the insulating resin layer, exposing a top of the protruding electrode. . 3. The semiconductor device according to claim 1, wherein an upper surface of the underfill material layer is substantially flush with a top of the bump electrode. 4. The semiconductor device according to claim 2, wherein a top of said bump electrode protrudes and is exposed from an upper surface of said underfill material layer by 1 μm to 200 μm. 5. The semiconductor device according to claim 1, wherein said protruding electrode is a solder ball. 6. The semiconductor device according to claim 4, wherein said projecting electrode is a solder ball, and said underfill material layer is made of a thermoplastic resin. 7. The elastic layer has a Young's modulus of 10 to 20.
The semiconductor device according to claim 2, wherein the range is 00 [kg / mm ² ]. 8. The semiconductor device according to claim 1, wherein said underfill material layer is an epoxy resin layer. 9. The semiconductor device according to claim 2, wherein an end of said elastic layer has an oblique side in a cross-sectional shape. 10. A step of preparing a semiconductor chip having a main surface on which a plurality of electrode pads are formed, and comprising a low elastic material on a region of the main surface of the semiconductor chip other than the plurality of electrode pads. Forming one of the plurality of electrode pads, one end of the plurality of electrode pads being connected, and the other end extending over the elastic body layer, and the contact pads being two-dimensionally arranged. Forming a wiring layer having: and a step of forming an insulating resin layer covering at least the wiring layer and the electrode pads on a region in the main surface of the semiconductor chip except for the plurality of contact pads. Forming a projecting electrode made of a conductive material on the contact pad; exposing a top of the projecting electrode on a region in a main surface of the semiconductor chip; Comprising a step of forming a Firu material layer, a method of manufacturing a semiconductor device. 11. The step of preparing the semiconductor chip,
The method of manufacturing a semiconductor device according to claim 10, wherein the method is a step of preparing a semiconductor wafer having a plurality of semiconductor chips formed on the surface. 12. A semiconductor chip having a main surface provided with a plurality of electrode pads; an elastic layer formed on a region of the main surface of the semiconductor chip other than the plurality of electrode pads; A plurality of contact pads two-dimensionally arranged in a region within the main surface of the elastic layer and on the elastic body layer; at least one of the plurality of contact pads electrically connected to at least one of the plurality of electrode pads; A wiring layer that is electrically connected to thereby perform rewiring connection; an insulating resin layer formed in a region excluding the plurality of contact pads and on a region in a main surface of the semiconductor chip; A semiconductor device comprising: a protruding electrode provided on each of the contact pads; and an underfill material layer provided on the insulating resin layer, exposing a top of the protruding electrode. A method of mounting a semiconductor device, wherein the semiconductor device is electrically connected to a wiring substrate having line electrodes and mounted on the substrate, wherein the main surface side of the semiconductor device and the main surface side of the wiring substrate are opposed to each other. Aligning the projecting electrode of the semiconductor device with the wiring electrode of the wiring substrate; contacting the projecting electrode of the semiconductor device with the wiring electrode of the wiring substrate; and underfilling the semiconductor device. A method for softening and melting a material layer by heating, and filling and sealing a gap between a main surface of the semiconductor device and a main surface of the wiring board with the underfill material layer. 13. The step of bringing the protruding electrode of the semiconductor device into contact with the wiring electrode of the wiring substrate includes pressing the top of the protruding electrode exposed from the underfill material layer against the wiring electrode of the wiring substrate. 13. The method of mounting a semiconductor device according to claim 12, wherein the method is performed by making a cut and making contact. 14. The semiconductor device according to claim 1, wherein a top of the protruding electrode of the semiconductor device is protruded and exposed from an upper surface of the underfill material layer, and the protruding electrode is a solder ball. A step of applying a solder paste having a melting point lower than the melting point of the solder balls to the wiring electrodes of the wiring board, wherein the projecting electrodes and the wiring electrodes are formed of a thermoplastic resin. The method according to claim 12, further comprising: melting the applied solder paste at a temperature lower than the melting point of the solder ball after the contacting.