JP2000077450A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce size and to decrease manufacturing cost for a semiconductor. SOLUTION: An anode-side terminal 26 comprising a silver-plated film is formed at an anode electrode 13 of a chip 25, wherein a diode element is formed. A cathode-side terminal 27 made of a conductive plate is formed at a cathode electrode 14. An insulating film 28 is formed between both terminals 26 and 27 at the side surface of the chip 25. When this diode 29 is manufactured, a silver-plated film is formed on the first main surface of a wafer, wherein a chip part is formed. The conductive plate is bonded to the second main surface of the water. A support body is temporarily bonded to the conductive plate of the wafer, and then the is cut into the chip and devided. Thereafter, in a state wherein the chip is supported by the supporting body, the insulating film is formed at the side surface of the chip. Since the device has a chip form in this way, the size of the diode can be reduced. Since the entire process of the diode manufacturing can be performed in a wafer state, manufacturing cost can be decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for manufacturing a semiconductor device, and more particularly to a technique for reducing the size of a semiconductor device, and more particularly to a technique effective for use in producing a diode.

[0002]

2. Description of the Related Art Generally, a diode is constructed as follows. Electrodes are formed on one principal surface of a square-plate-shaped semiconductor pellet (hereinafter, referred to as a pellet) in which a diode element is formed. The pellet is bonded to a tab on a main surface opposite to the electrode, and a first inner lead is integrally connected to the tab. A first outer lead is integrally connected to the first inner lead. On the side opposite to the first inner lead, a second inner lead integrally connected to the second outer lead is arranged, and the second inner lead is electrically connected to the electrode by a wire. Pellets, tabs, both inner leads and wires are resin-sealed by a resin sealing body, and both outer leads projecting outward from a pair of opposing side surfaces of the resin sealing body are bent into a gull-wing shape. .
The resin-sealed package and a pair of outer leads bent in a gull wing form a surface-mounted resin-sealed package.

[0003] Japanese Patent Application Laid-Open No. 9-7905 discloses an example describing a diode manufacturing technique.

[0004]

However, even if the size of the conventional diode is the smallest, it is 1.6 ×.
There is a size of 0.8 × 0.6 mm, and there is a limit in reducing the size and the manufacturing cost.

An object of the present invention is to provide an epoch-making semiconductor device capable of reducing the size and the manufacturing cost.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0007]

The outline of a typical invention among the inventions disclosed in the present application is as follows.

That is, in a semiconductor device, different electrodes are respectively formed on a pair of end surfaces of a semiconductor chip which are opposite to each other, a terminal made of a conductive film is formed on one electrode, and a conductive film is formed on the other electrode. A terminal made of a plate is formed, and an insulating film is formed between both terminals on the side surface of the chip.

In the method of manufacturing a semiconductor device described above, a method for forming a conductive film on one main surface of a semiconductor wafer in which a chip portion is formed, and a method for forming a conductive plate on a main surface on the opposite side of the semiconductor wafer. Bonding a conductive plate, a support bonding step in which a support is temporarily bonded to a conductive plate of the semiconductor wafer, a chip cutting step in which the semiconductor wafer is divided into chips, and the divided chip An insulating film forming step of forming an insulating film on a side surface of the chip while being supported by the support.

According to the above-mentioned means, since the chip is formed in a chip shape, the size can be extremely reduced. Therefore, the mounting area on a printed wiring board or the like can be reduced.

According to the method of manufacturing a semiconductor device described above,
Since all the steps of manufacturing a semiconductor device are performed in a wafer state, the number of parts and the number of processing steps can be reduced, and the manufacturing cost can be significantly reduced.

[0012]

1A and 1B show a diode according to an embodiment of the present invention. FIG. 1A is a perspective view and FIG. 1B is a front sectional view. FIG. 2 is a process chart showing a diode manufacturing method according to one embodiment of the present invention. FIG. 3 and subsequent drawings are schematic views showing the respective steps.

In the present embodiment, the semiconductor device according to the present invention is configured as a chip-type diode.
The diode 10 includes a square plate-shaped chip 25 in which a diode element is formed. A pair of electrodes, ie, an anode electrode 13 and a cathode Electrodes 14 are respectively formed. An anode terminal 26 formed by the silver plating film 18 is mechanically and electrically connected to the anode electrode 13. A cathode terminal 27 formed by a conductive plate 20 is mechanically and electrically connected to the cathode electrode 14 by a silver paste layer 19. An insulating film 28 is formed between the cathode terminal 27 and the anode terminal 26 on the outer peripheral surface of the chip 25.

Next, a method of manufacturing a diode according to an embodiment of the present invention will be described with reference to the process chart shown in FIG. With this description, the details of the configuration of the diode will be made clear together.

As shown in the process diagram of FIG. 2, first,
In a normal so-called pre-process in a diode production process, a diode element is formed for each chip portion arranged in a matrix shape on a silicon wafer as shown in FIG.

That is, in FIG. 3, a diode element (not shown) has a chip portion on a substrate 11 of a diode wafer (hereinafter, referred to as a wafer) 10 as a semiconductor wafer on which an integrated circuit including a semiconductor element is formed. 1
It is made every two. An anode electrode 13 is formed on a first main surface of each chip portion 12, and a cathode electrode 14 is formed on a second main surface on the opposite side. A protective film 15 made of an insulating material such as a polyimide resin is adhered to the first main surface of the substrate 11, and a through hole 16 is formed at a position of the protective film 15 facing the anode electrode 13. The anode electrodes 13 are opened so as to be exposed.

On the wafer 10 manufactured as described above, in the bump forming step shown in FIG. 2, a silver plating film as a conductive film is formed to a thickness of about 50 μm by a plating process as shown in FIG. It is formed to be.

First, as shown in FIG.
A nickel plating film 17 is thinly applied to the entire surface of the first main surface of the wafer 10 by electroless plating (chemical plating).

Next, as shown in FIG.
A silver plating film 18 is deposited on the nickel plating film 17 to a thickness of about 50 μm by electrolytic plating. At this time, the nickel plating film 1 is formed on the first main surface of the wafer 10.
7 is applied to the entire surface, the silver plating film 18 can also be formed on the entire first main surface of the wafer 10 by electrolytic plating.

Thereafter, in the conductive plate bonding step shown in FIG. 2, a conductive plate 20 is bonded to the second main surface of the wafer 10 by the silver paste layer 19 as shown in FIG.

The conductive plate 20 is made of a conductive metal such as copper or iron and is formed in a plate shape having a thickness of about 60 to 100 μm. An anti-oxidation film 21 such as a silver plating film or a solder plating film is formed on the main surface of the conductive plate 20 opposite to the bonding surface to prevent oxidation and enhance solderability.
Has been deposited.

The silver paste layer 19 is a layer formed by applying the silver paste to the bonding surface of the wafer 10 or the conductive plate 20 and then bonding the wafer 10 and the conductive plate 20 to each other. A conductive adhesive prepared by mixing silver powder into a resin-based adhesive.
Therefore, the conductive plate 20 is electrically connected to the cathode electrode 14 of each chip 12 of the wafer 10 via the silver paste layer 19.

Next, in the support plate bonding step shown in FIG. 2, a support 23 is attached to the conductive plate 20 on the second main surface of the wafer 10 by an adhesive layer 22 as shown in FIG. Temporarily bonded.

The support 23 supports the wafer 10 so that it does not fall apart when the wafer 10 is diced into chips in a later dicing step, and is formed in a flat plate shape by a resin such as vinyl chloride or polyethylene. I have. Since the adhesive layer 22 needs to allow peeling of the chip from the support body 23 in a subsequent pickup step, the adhesive layer 22 is formed of an adhesive capable of reducing the adhesive force by applying a solvent, irradiating ultraviolet rays, or the like. .

The conductive plate bonding step and the support plate bonding step may be performed so that the wafer 10 is bonded to the conductive plate 20 that has been bonded to the support 23 in advance.

Thereafter, in the dicing step shown in FIG. 2, the cutting groove 24 is formed along the scribing line which is the boundary between the adjacent chip portions 12 on the first main surface of the wafer 10 as shown in FIG. The wafer 10 is divided into each chip 25. At this time, the wafer 10 is so-called full-cut so that the chips 25 can be separated from each other. However, even if it is fully cut,
Since the chip 25 is in a state of being bonded to and supported by the support body 23 by the adhesive layer 22, the chip 25 does not fall apart.

As shown in FIG. 7, when the wafer 10 is divided into chips 25, an anode-side terminal 26 is formed on each chip 25 by the divided silver plating film 18, and a cathode 22 is formed by the conductive plate 22. The side terminal 27 is formed.

The formation of the cutting groove 24 is not limited to the use of a dicer, but may be, for example, a wire saw or a laser.

Next, in the insulating film forming step shown in FIG. 2, an insulating material such as epoxy resin is used on the side surface of each chip 25 to form an insulating film 28 as shown in FIG. Formed. The insulating film 28 can be formed very simply by pouring a material such as epoxy resin into the cutting groove 24 and attaching it to the side surface of the chip 25 which is the side wall surface of the cutting groove 24.

It is necessary that the insulating film 26 does not cover the anode terminal 26. As a method of preventing the insulating film 28 from covering the anode side terminal 26, for example, the surface of the silver plating film 18 is coated with a resist before dicing, and after the insulating film 28 is formed, the resist is removed. There is a way to remove it.

Thus, the diode 29 having the above configuration is manufactured.

For mounting on a printed wiring board or the like, FIG.
9, the diodes 29 are picked up one by one from the support 23 as shown in FIG.

In FIG. 9, the main surface of the diode 29 on the side of the anode side terminal 26 is held by vacuum suction by the vacuum suction head 30 and is separated from the support 23. On this occasion,
It is desirable to weaken the adhesive strength of the adhesive layer 22 by means such as irradiating ultraviolet rays. The picked-up diode 29 is regularly arranged on a carrier tape or the like,
Packed in packing containers.

When the adhesive is attached to the cathode-side terminal 27 which is the interface with the adhesive layer 22 and the solderability is reduced, the cleaning is performed in the cleaning step shown in FIG. It is desirable to wash the adhered adhesive.

By the way, the diode 2 according to the present embodiment
9 is small, for example, 0.25 × 0.25 × 0.5 mm, so that it is supplied to an automatic mounting device or the like while being supported by the support body 23, and is automatically attached to the printed wiring board. It is desirable to implement it in

However, the diodes 29 are picked up one by one from the support 23 and supplied to the user by being adhered to a carrier tape or the like.
It does not prevent supply to the automatic mounting apparatus by the parts feeder.

The diode 10 according to the above configuration is surface-mounted on a printed wiring board as shown in FIG.
That is, in a state where the anode side terminal 26 and the cathode side terminal 27 are aligned with the pair of lands 32 formed on the printed wiring board 31, respectively, the machine is mounted via the respective soldering portions 33 formed by reflow soldering. And electrically connected.

At this time, since the anode terminal 26 of the diode 29 is formed by the silver plating film 18 and the cathode terminal 27 is formed by the conductive plate 20, a mark such as a cathode band is not displayed. Also, the anode terminal 26 and the cathode terminal 27 can be distinguished. Further, since the diode 29 is not symmetrical, when the diode is supplied to the automatic mounting apparatus using a parts feeder, the mounting direction can be easily identified.

According to the above embodiment, the following effects can be obtained. Since the chip has anode and cathode terminals on both end surfaces and an insulating film on the side surface, the size of the diode can be extremely reduced, and the mounting density on the printed wiring board is improved. be able to.

Since all the steps of manufacturing the diode can be performed in a wafer state, the number of parts and the number of processing steps can be reduced, and the manufacturing cost can be significantly reduced.

Since the anode terminal of the diode is formed by a silver plating film and the cathode terminal is formed by a conductive plate, even if a mark such as a cathode band is not displayed, the anode terminal and the cathode terminal are not displayed. The terminal can be identified.

Since the diodes are not symmetrical, the mounting direction can be easily identified when the diodes are supplied to the automatic mounting apparatus using a parts feeder.

Although the invention made by the inventor has been specifically described based on the embodiment, the invention is not limited to the embodiment, and various modifications can be made without departing from the gist of the invention. Needless to say.

For example, the anode side terminal is not limited to being formed by a conductive film and the cathode side terminal is not necessarily formed by a conductive plate. The anode side terminal may be formed by a conductive plate and the cathode side terminal may be formed by a conductive film.

The conductive film for forming the terminals is not limited to being formed using silver, but may be formed using a conductive metal such as gold or copper.

The conductive plate for forming the terminals is not limited to being formed using copper or iron, but may be formed using a conductive metal such as silver or gold.

The adhesive for bonding the conductive plate and the wafer is not limited to silver paste, but may be solder, silver braze, or the like.

The insulating film is not limited to being formed by being attached to the side wall surface of the cutting groove, but may be formed by filling the cutting groove with an insulating material and cutting the filled resin layer at the center of the cutting groove.

The support is not limited to being formed as rigid as a support plate, but may be formed into a stretchable and flexible sheet or film.

In the above description, the case where the invention made by the present inventor is mainly applied to the diode production technology which is the background of the application has been described. However, the present invention is not limited to this case. And the like can be applied to all semiconductor devices having a pair of electrodes.

[0051]

The effects obtained by typical aspects of the invention disclosed in the present application will be briefly described as follows.

Since the chip has anode and cathode terminals formed on both end surfaces and an insulating film formed on the side surface, the size can be significantly reduced, and the mounting density on a printed wiring board can be improved. can do.

By performing all the manufacturing steps in the state of a wafer, the number of parts and the number of processing steps can be reduced, so that the manufacturing cost can be greatly reduced.

[Brief description of the drawings]

1A and 1B show a diode according to an embodiment of the present invention, wherein FIG. 1A is a perspective view and FIG. 1B is a front sectional view.

FIG. 2 is a process chart showing a method for manufacturing a diode according to an embodiment of the present invention.

FIG. 3 shows a state after a pre-process, where (a) is a plan view,
(B) is bb sectional drawing of (a).

4A and 4B show a silver plating film forming step, wherein FIG. 4A is an enlarged partial cross-sectional view after forming a nickel plating film, and FIG. 4B is an enlarged partial cross-sectional view after forming a silver plating film.

5A and 5B show a conductive plate bonding step, in which FIG. 5A is a partially omitted front view, and FIG. 5B is an enlarged partial sectional view.

6A and 6B show a support plate bonding step, in which FIG. 6A is a partially omitted front view, and FIG. 6B is an enlarged partial cross-sectional view.

7A and 7B show a state after the dicing step, in which FIG. 7A is a partially omitted front view, and FIG. 7B is an enlarged partial sectional view.

8A and 8B show an insulating film forming step, in which FIG. 8A is a partially omitted front view, and FIG. 8B is an enlarged partial sectional view.

FIG. 9 is a partially cutaway front view showing a pickup step, partly omitted.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Diode wafer (semiconductor wafer), 11 ... Substrate, 12 ... Chip part, 13 ... Anode electrode, 1
4: Cathode electrode, 15: Protective film, 16: Through hole, 17: Nickel plating film, 18: Silver plating film,
19: silver paste layer, 20: conductive plate, 21: antioxidant film, 22: adhesive layer, 23: support, 24: cut groove, 2
5 ... chip (semiconductor chip), 26 ... anode side terminal,
27: cathode side terminal, 28: insulating film, 29: diode (semiconductor device), 30: vacuum suction head, 31: printed wiring board, 32: land, 33: soldering part.

Claims (10)

[Claims] A different electrode is formed on each of a pair of front and back end faces of a semiconductor chip, a terminal made of a conductive film is formed on one electrode, and a terminal made of a conductive plate is formed on the other electrode. And an insulating film is formed between both terminals on the side surface of the chip. 2. The semiconductor device according to claim 1, wherein the conductive film forming the terminal is a film formed by plating. 3. The method according to claim 1, wherein the conductive plate is bonded by a conductive adhesive.
3. The semiconductor device according to claim 1. 4. The semiconductor device according to claim 1, wherein the insulating film is formed by being attached to a side surface of the chip. 5. The semiconductor device according to claim 1, wherein a diode element is formed in the semiconductor chip. 6. The method of manufacturing a semiconductor device according to claim 1, wherein a conductive film is formed on one main surface of the semiconductor wafer in which the chip portion is formed; A conductive plate bonding step in which a conductive plate is bonded to the opposite main surface; a support bonding step in which a support is temporarily bonded to the conductive plate of the semiconductor wafer; and a chip cutting step in which the semiconductor wafer is cut into chips. And a step of forming an insulating film on a side surface of the chip while the divided chip is supported by the support. A method for manufacturing a semiconductor device, comprising: 7. The method according to claim 6, wherein the conductive film is formed by plating. 8. The method for manufacturing a semiconductor device according to claim 6, wherein the conductive plate is bonded by a conductive adhesive. 9. The semiconductor device according to claim 6, wherein the insulating film is formed by pouring an insulating material into the cutting groove and attaching the material to a side surface of the chip which is a side wall surface of the cutting groove. 9. The method for manufacturing a semiconductor device according to claim 7, 7 or 8. 10. The method of manufacturing a semiconductor device according to claim 6, wherein the chip is picked up from the support after an insulating film forming step.