JPH11121641A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a semiconductor device very thin and to provide a satisfactory connection to a mounting board or the like, by providing a semiconductor device with a substantially flat back surface including a semiconductor chip, a sealed resin and externally connecting electrodes. SOLUTION: A semiconductor device has a substrate 1 having on its back a recessed cavity 1a, interconnections 2 provided on the surface of the substrate 1 and on the bottom of the cavity 1a, a semiconductor chip 3 electrically connected to the electrodes of the interconnections 2 by facedown bonding, add a sealed resin 4 for sealing the periphery of the chip 3 inserted into the cavity 1a of the substrate 1. The device also has externally connecting electrodes 5 and electronic parts 6. The electrodes 5 provided on side surfaces of the substrate 1 are electrically connected to the interconnection 2. The parts 6 are electrically connected to the interconnection 2 provided on the surface of the substrate 1. The back surface of the semiconductor device is formed into a substantially flat surface formed of the substrate l, the semiconductor chip 3, the sealed resin 4, and the externally connecting electrodes 5. As a result of this construction, an extremely thin semiconductor device can be achieved, and hence electronic equipment and the like can be downsized and reduced in weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device and a method of manufacturing the same, and more particularly, to a leadless chip carrier (LCC) type semiconductor device and a method of manufacturing the same.

[0002]

2. Description of the Related Art A conventional LCC type semiconductor device is disclosed in, for example, JP-A-9-8167. FIG.
1 is a longitudinal sectional view showing a conventional semiconductor device.

As shown in FIG. 6, a conventional semiconductor device is
A substrate 21 made of a base material such as a glass-epoxy material and having a cavity 21a formed on the back surface; a wiring 22 made of a conductive circuit pattern provided on the surface of the substrate 21 and the bottom of the cavity 21a of the substrate 21; 21
Back electrode 23 provided on the back surface of the substrate 21, an end face through-hole electrode 24 formed on the side surface of the substrate 21 and electrically connecting the back electrode 23 and the wiring 22, and fixed to the bottom of the cavity 21a of the substrate 21. Semiconductor chip 25, pads of semiconductor chip 25 and cavity 21a of substrate 21
A bonding wire 26 for electrically connecting the electrodes of the wiring 22 formed at the bottom of the semiconductor chip 25 to a bonding wire 26 for sealing the semiconductor chip 25;
Electronic components 28 such as semiconductor elements, resistance elements, and capacitance elements electrically connected to the wiring 22 provided on the surface of the substrate 21
And

[0004] Further, the prior art related to the present invention is as follows.
For example, it is disclosed in JP-A-63-147352, JP-A-4-346250 and JP-A-60-141129.

Japanese Patent Application Laid-Open No. 63-147352 discloses a module substrate having a wiring layer and external lead-out terminals on the top and bottom surfaces and internally connecting the wiring layer and the external lead-out terminals through through holes. A semiconductor laminated on an end and forming a cavity of a module substrate and a semiconductor storage container, and a lead of a film carrier tape connected to an electrode terminal. A semiconductor face-bonded to a wiring layer of the module substrate in the cavity. A thin module including a chip and a sealing resin for filling the semiconductor chip in a resin dam, wherein the back surface of the semiconductor chip to be face-bonded is ground or polished to near the element functional portion together with the resin dam surface and the sealing resin surface. Is disclosed.

[0006] Japanese Patent Application Laid-Open No. 4-346250 discloses that an IC chip is face-down in a cavity formed in a substrate, and an electrode of the IC chip and an electrode of a wiring of the substrate are joined via bumps. A semiconductor device in which the back surface and the side wall of the cavity are sealed with a resin is disclosed.

Japanese Utility Model Application Laid-Open No. 60-141129 discloses a leadless chip carrier having a large number of terminals on the outer peripheral side surface of the chip, and the terminal portions are inclined inward from the upper surface to the lower surface of the chip. A terminal structure is disclosed.

[0008]

In the conventional semiconductor device shown in FIG. 6, since the wiring 22 of the substrate 21 and the semiconductor chip 25 are connected by the bonding wires 26, it is necessary to seal the loop-shaped wires 26. Sealing resin 2
7 becomes thicker, and accordingly, the whole semiconductor device becomes thicker. As a result, there is a problem that it is not possible to reduce the size and weight of electronic devices and the like.

On the other hand, Japanese Patent Application Laid-Open No. 63-147352 discloses that the back surface of a semiconductor chip and a sealing resin surface are shaved to form a substantially flat shape. However, the back surface including external connection electrodes is shaved. However, there is no disclosure of the point of forming a substantially flat shape, and there is no description suggesting this.

Japanese Patent Application Laid-Open No. 4-346250 discloses that a semiconductor chip is face-down and an electrode of the semiconductor chip is connected to an electrode of a wiring.
It does not disclose that the back surface including the semiconductor chip, the sealing resin, and the external connection electrodes is formed in a substantially flat shape.

Further, Japanese Utility Model Laid-Open No. 60-141129 discloses that the terminal portion is inclined inward from the upper surface to the lower surface, but the lower portion of the terminal portion reaches the lower surface of the chip. There is no disclosure of forming a substantially flat back surface including a semiconductor chip, a sealing resin, and external connection electrodes.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a semiconductor device which is very thin and has good connection with a mounting board or the like, and a method of manufacturing the same. I do.

[0013]

According to the present invention, there is provided a semiconductor device comprising:
A substrate having a concave cavity on the back side, a wiring provided at the bottom of the cavity of the substrate, a semiconductor chip which is electrically connected face down to an electrode of the wiring, and a A sealing resin that is inserted and seals the periphery of the semiconductor chip, and an external connection electrode electrically connected to the wiring, and has a substantially flat back surface including the semiconductor chip, the sealing resin, and the external connection electrode. It is characterized by having.

The semiconductor device of the present invention also includes a substrate having a concave cavity formed on the back surface, a wiring provided at the bottom of the cavity of the substrate, and a face-down and electrically connected to an electrode of the wiring. Having a semiconductor chip, a sealing resin inserted into a cavity of the substrate and sealing the periphery of the semiconductor chip, and an external connection electrode provided on a side surface of the substrate and electrically connected to wiring, It has a substantially flat back surface comprising a substrate, a semiconductor chip, a sealing resin, and an external connection electrode.

It is preferable that the external connection electrode is provided so as to be inclined inward from the front side to the rear side of the substrate.

According to another aspect of the present invention, there is provided a semiconductor device including a substrate having a concave cavity formed on the back surface thereof, a wiring provided at the bottom of the cavity of the substrate, and an electrode which is face-down with the electrode of the wiring. Semiconductor chip, a sealing resin inserted into the cavity of the substrate and sealing the periphery of the semiconductor chip, and electrically connected to the wiring, and provided at a peripheral portion on the back surface side of the substrate. And a substantially flat back surface comprising a semiconductor chip, a sealing resin and an external connection electrode.

The electrodes of the semiconductor chip and the electrodes of the wiring of the substrate are electrically connected via bumps.

The semiconductor device may further include a wiring provided on the surface of the substrate, and an electronic component electrically connected to the wiring.

The method of manufacturing a semiconductor device according to the present invention comprises the steps of (1)
(2) a step of forming a substrate having a concave cavity formed on the back surface side and having a wiring provided at the bottom of the cavity and an external connection electrode electrically connected to the wiring;
A step of electrically connecting the semiconductor chip to a wiring electrode provided at the bottom of the cavity of the substrate by face-down, and (3) inserting a resin into the cavity of the substrate and surrounding the semiconductor chip. Sealing the
(4) a step of shaving the back surface including the semiconductor chip, the sealing resin and the external connection electrodes to a substantially flat shape to a predetermined thickness, and performing the steps in the order of (1) to (4). It is a feature.

According to the present invention, the semiconductor chip is face-down and electrically connected to the electrodes of the wiring provided at the bottom of the cavity of the substrate. Can be very low. Further, since the back surface of the semiconductor device is formed of a substantially flat surface including the semiconductor chip, the sealing resin, and the external connection electrodes, the back surface of the semiconductor chip can be ground without affecting the circuit, and the external connection can be performed. The connection between the electrodes and the mounting board is improved.

In particular, when the external connection electrode is provided to be inclined inward from the front surface side to the rear surface side of the substrate, the end thereof comes into contact with the rear surface of the semiconductor device in an inclined manner, so that the external connection electrode is mounted on the mounting board. The solder paste is easily brought into contact with the solder paste and the solder paste crawls along the external connection electrodes during reflow, so that good soldering is possible.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B show a semiconductor device according to a first embodiment of the present invention, wherein FIG. 1A is a longitudinal sectional view and FIG. 1B is a side view.

As shown in FIG. 1, the semiconductor device according to the first embodiment of the present invention has a concave cavity 1 on the back side.
a, a wiring 2 provided on the surface of the substrate 1 and at the bottom of the cavity 1a, a semiconductor chip 3 electrically connected face down to electrodes of the wiring 2; A sealing resin 4 inserted into the cavity 1a to seal the periphery of the semiconductor chip 3, and an external connection electrode 5 provided on the side surface of the substrate 1 and electrically connected to the wiring 2.
And an electronic component 6 electrically connected to the wiring 2 provided on the surface of the substrate 1.

The substrate 1 is made of, for example, an organic base material such as glass-epoxy or polyimide or a ceramic base material such as alumina. The thickness of the substrate 1 is, for example, about 600 μm.
m, and the depth of the cavity 1a is, for example, about 40
It is about 0 μm.

The thickness of the semiconductor chip 3 is, for example, about 100
μm, and the back surface of the semiconductor chip 3 is exposed to the back surface of the semiconductor device and becomes a part thereof.

As shown in FIG. 1B, a plurality of external connection electrodes 5 are provided in a slit shape from the peripheral portion to the side surface of the back surface of the semiconductor device.

The external connection electrode 5 may have any shape as long as it has a sufficient connection property. However, since the end face exposed on the back surface of the semiconductor is as small as the thickness of the conductor, the semiconductor device can be mounted. When mounted on the surface of the board, the external connection electrodes 5 extend inward from the front side of the substrate 1 toward the back side so that the contact with the solder paste is increased and good solder mounting is performed. Preferably, it is provided at an inclination. In this case, the end of the external connection electrode 5 is in contact with the back surface of the semiconductor device in an inclined manner. The lower part of the external connection electrode 5 may be coated with solder or the like in advance.

The conductor serving as the external connection electrode 5 is formed by forming a groove or a hole in the base material of the substrate 1 on the side to be the back surface of the semiconductor device and attaching the conductor to the inner surface by plating or the like.
Conductors are formed on the wiring 2 by plating or soldering.

For the face-down connection, a bump 7 made of gold or the like is formed on the semiconductor chip 3 or the substrate 1 side, and thermocompression bonding, solder, conductive paste, anisotropic conductive resin or the like is applied to the electrodes of the wiring 2 of the substrate 1. The method of connection is taken.

As the sealing resin 4, a resin such as epoxy, phenol or acrylic resin is used.
Protect the connection with

The back surface of the semiconductor chip 3 is ground together with the part of the substrate 1 by a polishing device or the like for grinding a silicon wafer to finish the semiconductor device thinly. At this time, the conductor serving as the external connection electrode 5 is also ground. The back surface of the semiconductor device is formed on a substantially flat surface including the substrate 1, the semiconductor chip 3, the sealing resin 4, and the external connection electrodes 5.

The external connection electrode 5, which is a part of the back surface of the semiconductor device, is electrically connected to a mounting board or the like.

FIGS. 2 and 3 are process diagrams showing a method for manufacturing a semiconductor device according to the present invention.

First, the substrate 1 is manufactured in the same manner as in a normal printed wiring board manufacturing process. On the back side of the substrate 1, a cavity 1a provided with an electrode for connecting the semiconductor chip 3 face-down to the bottom is formed by cutting with a cutting machine such as a router. Further, after the peripheral portion is cut in a slit shape with a disk-shaped cutting tooth, a conductor serving as the external connection electrode 5 is provided by forming a plated conductor on the inner surface (see FIG. 2A). The thickness of the substrate 1 is about 600
μm, and the depth of the cavity 1a is about 400 μm.

Next, a semiconductor chip 3 having a thickness of about 400 μm and having a gold bump 7 as an electrode is face-down connected to the electrode of the wiring 2 provided at the bottom of the cavity 1a by soldering.

Next, the gap in the cavity 1a is filled with the sealing resin 4, cured, and sealed (see FIG. 2B).

Next, the semiconductor chip 3 is ground from the back surface and thinned to about 100 μm, and at the same time, the whole semiconductor device is thinned to about 300 μm and the back surface is flat. At this time, the end of the external connection electrode 5 is formed so as to contact the back surface of the semiconductor device in an inclined manner (FIG. 3).
(A)).

By the above steps, a very thin layer of about 300 μm
A semiconductor device of about m is completed. A mounting board (not shown) is electrically connected to the external connection electrode 5 on the back surface of the semiconductor device, and an electronic component 6 is electrically connected to the wiring 2 provided on the surface of the substrate 1 on the front surface of the semiconductor device. (See FIG. 3B). Thus, a thin, high-density semiconductor device can be realized.

FIG. 4A is an explanatory view showing a mounting state when the external connection electrode 5 is formed to be inclined inward.
(B) is an explanatory view showing a mounting state when the external connection electrodes 5 are formed vertically.

The external connection electrode 5 is provided to be inclined inward from the front surface side of the substrate 1 to the rear surface side, so that the end on the rear surface side is in contact with the rear surface of the semiconductor device in an inclined manner. Therefore, when the back surface of the semiconductor device of the present invention is placed on the land 10 of the mounting board 9 on which the solder paste 11 is printed and aligned, the external connection electrode 5 (FIG. (A) is easier to contact the solder paste 11 than the external connection electrode 5 formed vertically (see FIG. 4B), and the solder paste 11 is connected to the external paste during reflow. Since it crawls along the electrode 5, good soldering becomes possible.

FIG. 5 is a longitudinal sectional view showing a semiconductor device according to the second embodiment of the present invention. As shown in FIG. 5A, the semiconductor device according to the second embodiment of the present invention
A substrate 1 having a concave cavity 1a formed on the back side;
Wiring 2 provided at the bottom of cavity 1a of substrate 1
And a semiconductor chip 3 electrically connected face down to the electrodes of the wiring 2 and a sealing resin 4 inserted into the cavity 1 a of the substrate 1 and sealing the periphery of the semiconductor chip 3.
And a substantially flat external connection electrode 5 which is electrically connected to the wiring 2 and is provided at a peripheral position on the back surface side of the substrate 1.

The back surface of the semiconductor device is formed as a substantially flat surface including the semiconductor chip 3, the sealing resin 4 and the external connection electrodes 5.

The substrate 1 is a flexible wiring board having a thickness of about 50 μm using a polyimide film as a base material. The thickness of the semiconductor chip 3 is, for example, about 100 μm.

The substrate 1 has a reinforcing plate 12 having a thickness of 150 μm adhered to the periphery of the surface thereof, and a concave cavity 1 a is formed on the back surface side at the center. The semiconductor chip 3 is face-down connected to the electrode of the wiring 2 provided at the bottom of the cavity 1 a via the bump 7.

A conductor forming the external connection electrode 5 is provided in the peripheral portion on the back surface of the substrate 1 by forming a metal such as solder into a convex shape.

In manufacturing, after the semiconductor chip 3 is sealed with the sealing resin 4, the back surface side of the semiconductor device is ground to form the semiconductor device as thin as about 300 μm. External connection electrodes 5 are exposed in a land-grid array form such that they are in horizontal contact with each other on the back surface of the ground semiconductor device.

As shown in FIG. 5B, a wiring 2 may be provided on the surface of the semiconductor device, and an electronic component 6 electrically connected to the wiring 2 may be mounted.

The present invention is not limited to the above embodiment, and various changes can be made within the scope of the technical matters described in the claims.

[0049]

According to the present invention, the following excellent effects can be obtained. (1) Since the semiconductor chip is face-down and electrically connected to the wiring electrodes provided at the bottom of the cavity of the substrate, the height of the sealing resin is extremely reduced as compared with the case where bonding wires are used. Can be lowered. In addition, since the back surface of the semiconductor device is formed as a substantially flat surface including the semiconductor chip, the sealing resin, and the external connection electrodes, the back surface of the semiconductor chip can be ground without affecting the circuit. Therefore, a very thin semiconductor device can be realized, and the size and weight of electronic devices and the like can be reduced. (2) Since the back surface of the semiconductor device is formed as a substantially flat surface including the semiconductor chip, the sealing resin, and the external connection electrodes, the external connection electrodes can be connected well to the mounting board and the like. it can. Therefore, a highly reliable semiconductor device can be realized.

In particular, when the external connection electrode is provided to be inclined inward from the front surface side to the rear surface side of the substrate, the end thereof comes into contact with the rear surface of the semiconductor device in an inclined manner, so that (3) Good soldering is possible because the solder paste creeps along the external connection electrodes during reflow. (3) Electronic components and the like are mounted on the surface of the semiconductor device. Since the semiconductor device can be mounted, a high-density semiconductor device can be realized.

[Brief description of the drawings]

FIG. 1A is a longitudinal sectional view showing a semiconductor device according to a first embodiment of the present invention, and FIG. 1B is a side view thereof.

FIGS. 2A and 2B are process diagrams showing a method for manufacturing a semiconductor device according to the present invention.

FIGS. 3A and 3B are process diagrams showing a method for manufacturing a semiconductor device according to the present invention.

FIG. 4A is an explanatory view showing a mounting state when an external connection electrode is formed to be inclined inward, and FIG.
FIG. 9 is an explanatory diagram showing a mounting state when the external connection electrodes are formed vertically.

FIG. 5 is a longitudinal sectional view showing a semiconductor device according to a second embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a conventional semiconductor device.

[Explanation of symbols]

 1: substrate 1a: cavity 2: wiring 3: semiconductor chip 4: sealing resin 5: external connection electrode 6: electronic component 7: bump 9 mounting board 10 land 11 solder paste 12 reinforcing plate

Claims (7)

[Claims] A substrate provided with a concave cavity on the back surface side, a wiring provided at a bottom of the cavity of the substrate, a semiconductor chip electrically connected face down to an electrode of the wiring; A sealing resin inserted into a cavity of the substrate to seal around the semiconductor chip; and an external connection electrode electrically connected to the wiring, wherein the semiconductor chip, the sealing resin, and the external connection A semiconductor device having a substantially flat back surface including electrodes. 2. A substrate having a concave cavity formed on the back side, a wiring provided at the bottom of the cavity of the substrate, and a semiconductor chip which is electrically connected face down to an electrode of the wiring. A sealing resin inserted into a cavity of the substrate to seal around the semiconductor chip, and an external connection electrode provided on a side surface of the substrate and electrically connected to the wiring, A semiconductor device having a substantially flat back surface comprising a semiconductor chip, a sealing resin, and an external connection electrode. 3. The semiconductor device according to claim 2, wherein the external connection electrode is provided to be inclined inward from the front side to the back side of the substrate. 4. A substrate having a concave cavity formed on the back side, a wiring provided at the bottom of the cavity of the substrate, and a semiconductor chip which is electrically connected face down to an electrode of the wiring. A sealing resin inserted into the cavity of the substrate and sealing the periphery of the semiconductor chip; and a substantially flat external part electrically connected to the wiring and provided at a peripheral portion on the back side of the substrate. A semiconductor device comprising: a connection electrode; and a substantially flat back surface including the semiconductor chip, a sealing resin, and an external connection electrode. 5. The semiconductor device according to claim 1, wherein the electrodes of the semiconductor chip and the electrodes of the wiring of the substrate are electrically connected via bumps. . 6. The semiconductor device according to claim 1, further comprising a wiring provided on a surface of the substrate, and an electronic component electrically connected to the wiring. Semiconductor device. 7. A step of forming a substrate in which a concave cavity is formed on the back surface side, the substrate provided with a wiring provided at the bottom of the cavity, and an external connection electrode electrically connected to the wiring. (2) a step of face-down electrically connecting the semiconductor chip to an electrode of a wiring provided on a bottom of the cavity of the substrate; and (3) inserting a resin into the cavity of the substrate, (1) a step of sealing the periphery of the semiconductor chip, and (4) a step of shaving the back surface including the semiconductor chip, the sealing resin, and the external connection electrode to a substantially flat shape to a predetermined thickness. ) To (4), in which order.