JP2010283158A - Semiconductor device and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin semiconductor device and a method for manufacturing the same. <P>SOLUTION: A method for manufacturing a semiconductor device includes a process of mounting a semiconductor chip 11 and a metal plate 12 apart on a first resin sheet 30 and pressing the semiconductor chip 11 to embed a part in the first resin sheet 30; a process of connecting the semiconductor chip 11 and the metal plate 12 via a connection conductor 14; a process of laminating a second resin sheet 34 on the first resin sheet 30, in such a manner as to cover the semiconductor chip 11, the metal plate 12 and the connection conductor 14; a process of removing the first resin sheet 30 and a part embedded in the first resin sheet 30 to expose the semiconductor chip 11 and the metal plate 12; a process of forming a protection film 18, having a first opening 18a exposing the semiconductor chip 11 on the second resin sheet 34 and a second opening 18b exposing the metal plate 12; and a process of forming first and second external electrodes 16 and 17 in the semiconductor chip 11 and the metal plate 12 with the protection film 18 as a mask. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a semiconductor device and a manufacturing method thereof.

  In recent years, along with the widespread use of various small electronic devices typified by mobile phones and mobile portable terminals, surface-mount packages in which electrode leads can be soldered directly to a substrate have become mainstream in resin-encapsulated semiconductor devices. It is coming.

  2. Description of the Related Art Conventionally, a semiconductor device in which a semiconductor chip is mounted on a first electrode lead, the semiconductor chip and the second electrode lead are connected via a wire, and is molded with a resin is a first electrode lead that supports a semiconductor chip that is not originally required ( Since the support substrate is used, there is a problem that it is difficult to reduce the thickness of the semiconductor device.

On the other hand, a semiconductor device is known that is thinned without using a support substrate that supports a semiconductor chip (see, for example, Patent Document 1 or Patent Document 2).
In the semiconductor device disclosed in Patent Document 1, after forming a separation groove in a conductive foil, a circuit element is mounted and wire-bonded, an insulating resin is applied using the conductive foil as a supporting substrate, and then inverted. This time, the conductive foil is polished using the insulating resin as a supporting substrate to separate the conductive path, and the insulating resin located outside the conductive path is cut to form one package.

  The semiconductor device disclosed in Patent Document 2 is sealed with resin by wire bonding in a state where a semiconductor element is bonded and fixed on a metal plate on which electroforming for external electrodes is formed. And it cuts the resin sealing body obtained by peeling a metal plate after resin sealing, and it is set as 1 package.

  The height of the semiconductor device depends on the thickness of the external chip, the thickness of the semiconductor chip, the height of the wire loop, the thickness of the mold resin, and the like, but is mainly limited by the thickness of the semiconductor chip. In other words, the semiconductor chip is not originally necessary, but since it has a semiconductor substrate having a thickness necessary for securing the handling property when mounting the semiconductor chip and the shock resistance when bonding, the mounting and bonding If the thickness of the semiconductor chip can be reduced afterwards, the semiconductor device can be further reduced in thickness.

However, the semiconductor device disclosed in Patent Document 1 or Patent Document 2 has a semiconductor chip having the same thickness as the semiconductor wafer when dicing, and it is difficult to further reduce the thickness of the semiconductor device. There is.
Furthermore, there is no disclosure or suggestion about reducing the thickness of the semiconductor chip later in the assembly process.

JP 2001-217372 A JP 2006-351835 A

  The present invention provides a thin semiconductor device and a method for manufacturing the same.

  In the method for manufacturing a semiconductor device of one embodiment of the present invention, a semiconductor chip and a metal plate are placed separately on a first resin sheet, the semiconductor chip is pressed, and a part of the semiconductor chip is transferred to the first resin sheet. A step of embedding in a resin sheet; a step of electrically connecting the semiconductor chip and the metal plate via a connection conductor; and a second resin sheet covering the semiconductor chip, the metal plate, and the connection conductor. Laminating on the first resin sheet, removing the first resin sheet, removing a part of the semiconductor chip embedded in the first resin sheet exposed earlier in the middle, A step of exposing the semiconductor chip and the metal plate, and forming a protective film having a first opening exposing the semiconductor chip and a second opening exposing the metal plate on the second resin sheet. It is characterized by comprising the steps of forming first and second external electrodes on the semiconductor chip and the metal plate the protective film as a mask.

  A semiconductor device of one embodiment of the present invention includes a semiconductor chip, a metal plate that is spaced apart on the same plane as the semiconductor chip, and one electrode connected to an electrode pad formed on the first surface of the semiconductor chip. And the other is a connection conductor connected to the first surface of the metal plate, a second surface facing the first surface of the semiconductor chip, and a second surface facing the first surface of the metal plate. A first surface formed on the second surface of the semiconductor chip, the second surface of the semiconductor chip, and the resin that seals the semiconductor chip, the metal plate, and the connection conductor, respectively. And a second external electrode, and a protective film formed on the resin so as to surround the first and second external electrodes.

  According to the present invention, a thin semiconductor device and a manufacturing method thereof can be obtained.

1A and 1B are diagrams illustrating a semiconductor device according to a first embodiment of the present invention, in which FIG. 1A is a plan view thereof, and FIG. 1B is cut along a line AA in FIG. FIG. 1C is a sectional view taken along the line BB in FIG. 1A and viewed in the direction of the arrow. Sectional drawing which shows the manufacturing method of the semiconductor device which concerns on the Example of this invention in process order. Sectional drawing which shows the manufacturing method of the semiconductor device which concerns on the Example of this invention in process order. 4A and 4B are diagrams showing a semiconductor device according to an embodiment of the present invention in comparison with a semiconductor device of a comparative example, in which FIG. 4A is a cross-sectional view showing the semiconductor device of the present embodiment, and FIG. Sectional drawing which shows an apparatus. FIG. 5A is a plan view of another semiconductor device according to an embodiment of the present invention, and FIG. 5B is a cross-sectional view taken along the line CC in FIG. A cross-sectional view. FIG. 6A is a plan view of another semiconductor device according to an embodiment of the present invention, and FIG. 6B is a cross-sectional view taken along line DD in FIG. FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  A semiconductor device according to an embodiment of the present invention will be described with reference to FIGS. 1A and 1B are diagrams showing the semiconductor device of this embodiment, FIG. 1A is a plan view thereof, and FIG. 1B is cut along the line AA in FIG. 1C is a cross-sectional view taken along the line BB in FIG. 1A and viewed in the direction of the arrow, and FIGS. 2 and 3 are cross-sectional views sequentially showing the manufacturing steps of the semiconductor device. 4 is a view showing the semiconductor device in comparison with the semiconductor device of the comparative example. FIG. 4A is a cross-sectional view showing the semiconductor device of this embodiment, and FIG. 4B is a cross-sectional view showing the semiconductor device of the comparative example. It is.

  As shown in FIG. 1, the semiconductor device 10 of the present embodiment includes a semiconductor chip 11, a metal plate 12 that is spaced apart on the same plane as the semiconductor chip 11, and one of the first surfaces of the semiconductor chip 11. A wire (connecting conductor) 14 connected to the electrode pad 13 formed on 11 a and the other connected to the first surface 12 a of the metal plate 12, and a second facing the first surface 11 a of the semiconductor chip 11. A resin 15 that seals the semiconductor chip 11, the metal plate 12, and the wire 14 is provided by exposing the surface 11 b and the second surface 12 b facing the first surface 12 a of the metal plate 12.

  Furthermore, the semiconductor device 10 includes first and second external electrodes 16 and 17 formed on the second surface 11b of the semiconductor chip 11 and the second surface 12b of the metal plate 12, and first and second external electrodes. 16 and 17 and a protective film 18 formed on the resin 15 so as to surround the periphery.

  The semiconductor chip 11 is, for example, a vertical diode having a thickness t1 of about 50 μm, and has an anode on the first surface 11a side and a cathode on the second surface 11b side, an electrode pad 13 is an anode terminal, and a first external electrode Reference numeral 16 denotes a cathode terminal.

The metal plate 12 is an electrode lead of a lead frame having a thickness t2 equal to the thickness t1 of the semiconductor chip 11, for example, an alloy material of iron and copper (main component is iron) plated with nickel or solder.
The electrode pad 13 is, for example, an aluminum pad that is in ohmic contact with the anode of a vertical diode.
The wire 14 is, for example, a gold (Au) wire having a bonding loop height of about 20 μm that is ultrasonically bonded to the electrode pad 13 and the metal plate 12.

  The resin 15 is, for example, a mold resin obtained by curing after curing a semi-cured epoxy resin film. The height from the top of the bonding loop to the upper surface of the mold resin is about 50 μm.

The first and second external electrodes 16 and 17 are, for example, copper (Cu) plating electrodes having a thickness of about 40 μm, and tin (Sn) plating or nickel gold (Ni / Au) plating is packaged on the Cu. Yes.
For example, as will be described later, the protective film 18 is a film in which a resist film is left as a mask when the first and second external electrodes 16 and 17 are plated.

  Therefore, the height H of the semiconductor device 10 is the thickness of the first and second external electrodes 16 and 17, the thickness of the semiconductor chip 11, the height of the bonding loop, and the height from the top of the bonding loop to the upper surface of the mold resin. The sum is about 160 μm.

  Next, a method for manufacturing the semiconductor device 10 will be described. 2 and 3 are cross-sectional views showing the manufacturing process of the semiconductor device 10 in order.

First, as shown in FIG. 2A, a semiconductor chip 11 having a thickness t0, for example, 150 μm, which is the same as the thickness of the semiconductor wafer when diced, and a metal t2, for example, 50 μm, which is thinner than the thickness t0. The plate 12 is placed on the first resin sheet 30, for example, a semi-cured epoxy resin sheet having a thickness of 200 μm so as to be spaced apart.
In this embodiment, a set of a plurality of semiconductor chips 11 and metal plates 12 are placed on a long first resin sheet 30 at a predetermined interval, and finally cut along a dicing line 31. 1 package.

Next, as shown in FIG. 2B, since the thickness t0 of the semiconductor chip 11 is thicker than the thickness t2 of the metal plate 12, the first resin sheet 30 is placed on the base 32, and the semiconductor chip 11 is mounted. The pressure plate 33 is pressed.
Next, as shown in FIG. 2C, a part of the semiconductor chip 11 is embedded in the first resin sheet 30 so that the height of the upper surface of the semiconductor chip 11 and the height of the upper surface of the metal plate 12 are aligned.
Next, as shown in FIG. 2D, the wire 14 is ultrasonically bonded to the electrode pad 13 and the metal plate 12 of the semiconductor chip 11, and the electrode pad 13 and the metal plate 12 of the semiconductor chip 11 are electrically connected. Connect.

  Next, as shown in FIG. 3A, for example, a second resin sheet 34 made of the same material as the first resin sheet 30 and having a thickness of about 120 μm covers the semiconductor chip 11, the metal plate 12, and the wires 14. After filling the first resin sheet 30 with pressure and maintaining the clearance (the height of the package), it fills the shape of the semiconductor chip 11, the metal plate 12 and the wire 14 to be wrapped without gaps, and after-cure Apply.

  Thereby, the 1st resin sheet 30 and the 2nd resin sheet 34 are integrated, and it becomes the same as the normal thermosetting epoxy resin, and the semiconductor chip 11, the metal plate 12, and the wire 14 are molded with resin.

  In the present specification, even after the first resin sheet 30 and the second resin sheet 34 are integrated by after-curing, they are referred to as the first resin sheet 30 and the second resin sheet 34 for convenience.

Next, as shown in FIG. 3B, the first resin sheet 30 is removed by, for example, lapping, and the portion embedded in the first resin sheet 30 that is exposed first in the middle is wrapped to form a semiconductor chip. 11 and the metal plate 12 are exposed.
As a result, the thickness of the semiconductor chip 11 is subsequently reduced from t0 to t1, and the thickness t1 of the semiconductor chip 11 is equal to the thickness t2 of the metal plate 12.

  Next, as shown in FIG. 3C, a protective film 18 having a first opening 18a exposing the entire semiconductor chip 11 and a second opening 18b exposing a part of the metal plate 12, for example, A resist film patterned by photolithography is formed on the second resin sheet 34.

Next, as shown in FIG. 3D, Cu is plated to a thickness of about 40 μm by electroplating using the protective film 18 as a mask, and Sn or nickel gold (Ni / Au) exterior plating is formed on the Cu. Apply. As a result, the first external electrode 16 is formed on the semiconductor chip 11 and the second external electrode 17 is formed on the metal plate 12.
Next, the second resin sheet 34 is diced along the dicing line 31 using the blade 35, and separated into individual packages.

  As a result, a thin semiconductor having a semiconductor chip 11 having a thickness t0 necessary to ensure handling at the time of mounting and impact resistance at the time of bonding in the assembly process, and having a thickness reduced to t1 after the bonding is completed. Device 10 is obtained.

Since the support substrate and the metal plate are not disposed in the portion corresponding to the dicing line 31, the wear and breakage of the blade 35 during dicing can be greatly reduced. Since the first and second resin sheets 30 and 34 are stacked and molded by after-curing, a mold for molding is unnecessary.
Further, by reducing the thickness of the semiconductor chip 11, it is possible to expect improvement in characteristics of the semiconductor device 10 such as reduction of conduction resistance and improvement of heat dissipation.

  4A and 4B are diagrams showing the semiconductor device of this embodiment in comparison with the semiconductor device of the comparative example. FIG. 4A is a cross-sectional view showing the semiconductor device of this embodiment, and FIG. It is sectional drawing which shows a semiconductor device. Here, the comparative example is a semiconductor device assembled by pressing the semiconductor chip 11 without embedding a part of the semiconductor chip 11 in the first resin sheet 30. First, a semiconductor device of a comparative example will be described.

As shown in FIG. 4B, the semiconductor device 50 of the comparative example has a thickness necessary for securing handling properties when mounted on the first resin sheet 30 and impact resistance when bonding the wire 14. A semiconductor chip 51 having t0 is provided.
As a result, the height H2 of the semiconductor device 50 is limited by the thickness t0 of the semiconductor chip 51, and it is difficult to make the semiconductor device 50 thinner.

On the other hand, the semiconductor device 10 according to the present embodiment has a thickness t0 necessary for securing handling properties when mounted on the first resin sheet 30 and impact resistance when bonding the wire 14 before assembly. However, the semiconductor chip 11 is reduced in thickness from t0 to t1 by removing a semiconductor substrate that is not necessary after mounting and bonding.
As a result, the height H1 of the semiconductor device 10 is lowered according to the reduction amount of the thickness of the semiconductor chip 11, so that a thinner semiconductor device can be obtained.

As described above, in the present embodiment, the thickness t0 necessary for securing the handling property when mounted on the first resin sheet 30 and the shock resistance when bonding the wire 14 is obtained before assembly. The semiconductor chip 11 is thinned from t0 to t1 afterwards by removing the semiconductor substrate which is not necessary after the mounting and bonding.
As a result, the semiconductor device can be reduced in thickness while maintaining sufficient assembly. Therefore, a thin semiconductor device and a manufacturing method thereof can be obtained.

  Here, the case where the first resin sheet 30 and a part of the semiconductor chip 11 embedded in the first resin sheet 30 are removed to expose the semiconductor chip 11 and the metal plate 12 has been described. It is also possible to polish the sheet 34, the semiconductor chip 11 and the metal plate 12, and further reduce the thickness of the second resin sheet 34, the semiconductor chip 11 and the metal plate 12. According to this, it is possible to further reduce the thickness of the semiconductor device without being controlled by the thickness t2 of the metal plate 12.

  Although the case where the semiconductor chip 11 is embedded in the first resin sheet 30 has been described so that the upper surface 11a of the semiconductor chip 11 and the upper surface 12a of the metal plate 12 are on the same plane, the amount embedded is not particularly limited.

The upper surface 11a of the semiconductor chip 11 may be higher than the upper surface 12a of the metal plate 12, that is, not on the same plane, as long as a target thin semiconductor device can be obtained.
Further, the upper surface 11 a of the semiconductor chip 11 does not need to be lower than the upper surface 12 a of the metal plate 12. This is because the thickness of the semiconductor device is controlled by the thickness t2 of the metal plate 12.

  The case where the thickness t0 of the semiconductor chip 11 is larger than the thickness t2 of the metal plate 12 has been described. However, when the thickness t0 of the semiconductor chip 11 is smaller than the thickness t2 of the metal plate 12, the metal plate 12 is changed to the first plate. By embedding in the resin sheet 30, it can implement similarly.

Although the case where the semiconductor chip 11 is a two-terminal vertical diode has been described, the present invention can be similarly implemented even if it is a three-terminal vertical transistor.
5A and 5B are diagrams showing a semiconductor device having a semiconductor chip in which a three-terminal vertical transistor is formed. FIG. 5A is a plan view thereof, and FIG. 5B is a CC line in FIG. It is sectional drawing which cut | disconnected along and was seen in the arrow direction.

  As shown in FIG. 5, the semiconductor device 60 includes a semiconductor chip 61 in which a three-terminal vertical transistor is formed, and a metal that is arranged on the same plane as the semiconductor chip 61 so as to sandwich the semiconductor chip 61. The plates 12 and 62, one of which is connected to the electrode pad 13 formed on the first surface 61a of the semiconductor chip 61 and the other of which is connected to the first surface 12a of the metal plate 12 and one of which is a semiconductor A wire 64 connected to the electrode pad 63 formed on the first surface 61 a of the chip 61 and the other connected to the first surface 62 a of the metal plate 62.

  Further, the semiconductor device 60 exposes the second surface 61b facing the first surface 61a of the semiconductor chip 61 and the second surfaces 12b and 62b facing the first surfaces 12a and 62a of the metal plates 12 and 62, respectively. The resin 15 for sealing the semiconductor chip 61, the metal plates 12, 62 and the wires 14, 64, the first external electrode 16 formed on the second surface 61b of the semiconductor chip 61, and the metal plate 12 are formed. On the resin 15 so as to surround the second external electrode 17 formed, the third external electrode 65 formed on the second surface 62b of the metal plate 62, and the first to third external electrodes 16, 17, 65. And a protective film 18 formed on the substrate.

  The semiconductor chip 61 is thinned after completion of mounting and bonding, and the thickness t1 of the semiconductor chip 61 and the thickness t2 of the metal plates 12 and 62 are set to be equal to each other. A thin semiconductor device 60 having a semiconductor chip 61 having a three-terminal vertical transistor is obtained.

  Although the case where the connecting conductor is the wire 14 has been described, it may be a plate or a strip-like connecting conductor. 6A and 6B are diagrams showing a semiconductor device having a plate-like connection conductor, FIG. 6A being a plan view thereof, and FIG. 6B being cut along the line DD in FIG. It is sectional drawing seen.

As shown in FIG. 6, the semiconductor device 70 includes a plate-like connection conductor 71 having one end connected to the electrode pad 13 of the semiconductor chip 11 and the other end connected to the metal plate 12. The plate-like connection conductor 71 is an alloy containing, for example, aluminum as a main component and a small amount of silicon added.
Since the upper surface of the semiconductor chip 11 and the upper surface of the metal plate 12 are on the same plane, the plate-like connection conductor 71 can be easily ultrasonically bonded to the semiconductor chip 11 and the metal plate 12.

  By changing the connecting conductor from the wire 14 to the plate-like connecting conductor 71, the height of the loop of the wire 14 becomes unnecessary, so that the height H3 of the semiconductor device 70 is lower than the height H1 of the semiconductor device 10 by δ, It is possible to further reduce the thickness of the semiconductor device 70.

The present invention can be configured as described in the following supplementary notes.
(Supplementary Note 1) After the semiconductor chip and the metal plate are exposed, the second resin sheet, the semiconductor chip, and the metal plate are further polished, and the second resin sheet, the semiconductor chip, and the metal plate are further polished. The method of manufacturing a semiconductor device according to claim 12, wherein the semiconductor device is thinned.

(Additional remark 2) The said metal plate is a lead terminal of a lead frame, The manufacturing method of the semiconductor device of Claim 1 thru | or 3 characterized by the above-mentioned.

(Supplementary note 3) The method of manufacturing a semiconductor device according to claim 1, wherein the connection conductor is a wire, plate, or strip-shaped connection conductor.

10, 50, 60, 70 Semiconductor device 11, 51, 61 Semiconductor chip 12, 62 Metal plate 13, 63 Electrode pad 14, 64 Wire (connection conductor)
15 Resin 16 1st external electrode 17 2nd external electrode 18 Protective film 18a, 18b 1st, 2nd opening 30 1st resin sheet 31 Dicing line 32 Base 33 Holding plate 34 2nd resin sheet 35 Blade 65 3rd external electrode 71 Plate connection conductor

Claims (5)

Placing the semiconductor chip and the metal plate separately on the first resin sheet, pressing the semiconductor chip, and embedding a part of the semiconductor chip in the first resin sheet;
Electrically connecting the semiconductor chip and the metal plate via a connection conductor;
Laminating a second resin sheet on the first resin sheet so as to cover the semiconductor chip, the metal plate and the connection conductor;
Removing the first resin sheet, removing a part of the semiconductor chip embedded in the first resin sheet exposed earlier in the middle, and exposing the semiconductor chip and the metal plate;
A protective film having a first opening for exposing the semiconductor chip and a second opening for exposing the metal plate is formed on the second resin sheet, and the semiconductor chip and the protective film are used as a mask. Forming first and second external electrodes on a metal plate;
A method for manufacturing a semiconductor device, comprising:   2. The semiconductor device according to claim 1, wherein a part of the semiconductor chip is embedded in the first resin sheet so that an upper surface of the semiconductor chip and an upper surface of the metal plate are aligned on the same plane. Manufacturing method.   2. The method of manufacturing a semiconductor device according to claim 1, wherein the first and second external electrodes are formed by a plating method. A semiconductor chip;
A metal plate spaced apart on the same plane as the semiconductor chip;
A connection conductor, one connected to the electrode pad formed on the first surface of the semiconductor chip and the other connected to the first surface of the metal plate;
The second surface facing the first surface of the semiconductor chip and the second surface facing the first surface of the metal plate are exposed to seal the semiconductor chip, the metal plate, and the connection conductor. Resin to stop,
First and second external electrodes formed on the second surface of the semiconductor chip and the second surface of the metal plate;
A protective film formed on the resin so as to surround the first and second external electrodes;
A semiconductor device comprising:   6. The semiconductor device according to claim 5, wherein the upper surface of the semiconductor chip and the upper surface of the metal plate are on the same plane, and the thickness of the semiconductor chip is equal to the thickness of the metal plate.

Images