WO2018088080A1

WO2018088080A1 - Semiconductor device and method for producing same

Info

Publication number: WO2018088080A1
Application number: PCT/JP2017/036353
Authority: WO
Inventors: 啓年草間; 匠野村
Original assignee: 株式会社デンソー
Priority date: 2016-11-14
Filing date: 2017-10-05
Publication date: 2018-05-17
Also published as: JP2018081967A

Abstract

This semiconductor device is provided with: a lead (2) which has one surface (21), the other surface (22) that is on the reverse side of the one surface (21), and a lateral surface (23) that connects the one surface (21) and the other surface (22) to each other; a sealing body which is integrated with the lead (2) by means of a resin; and a resin burr (4) which is composed of a part of the resin and adheres to the lead (2), while protruding from the sealing body. A peel-off prevention part (25) which prevents the resin burr (4) from peeling off from the lead (2) by enhancing the adhesion between the lead (2) and the resin burr (4) is formed at a corner part (24) between the one surface (21) and the lateral surface (23).

Description

Semiconductor device and manufacturing method thereof

Cross-reference to related applications

This application is based on Japanese Patent Application No. 2016-221771 filed on Nov. 14, 2016, the contents of which are incorporated herein by reference.

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

In the manufacture of semiconductor devices, after the step of resin-sealing semiconductor chips and die pads, etc., the sealing body, ie, the package and the lead are supported by the die, and the tie bar that connects the leads is cut by shearing with a cut punch. A process is performed.

In the tie bar cutting process, in order to avoid the cut punch coming into contact with the sealing body, a place slightly separated from the sealing body is cut. In a region surrounded by the sealing body, two adjacent leads, and a tie bar, resin burrs are generated due to the resin flowing out from between the molds during resin sealing. A part of the resin burr is removed by tie bar cutting, and the remaining part protrudes from the sealing body and remains attached to the lead.

Residual resin burrs are in a state where cracks are generated due to impact during shearing and chipping is likely to occur. In particular, since the lead is made of metal, the adhesiveness is low at the interface between the residual resin burr and the lead, and peeling between the residual resin burr and the lead tends to occur or chipping easily occurs.

Therefore, residual resin burrs easily fall off the leads due to vibrations and impacts applied during handling and conveyance in the post-process. If the resin burr falls off and adheres to the lead frame or package of the next product, when the lead frame is clamped with a cutting die or the like, a step may be generated due to the presence of the adhered resin. A large force acts on the package portion at the base of the lead, and the package may be cracked or chipped.

In this regard, Patent Document 1 proposes a method for suppressing resin burrs from remaining during tie bar cutting. Specifically, the die and the resin burr are separated from each other, and the resin burr between the leads is hit with a cut punch to cut. Then, since the resin burr adhering to the side surface of the lead is not supported by the die, it peels off at the interface with the side surface of the lead.

JP 2003-17643 A

However, since the resin burr is integrated with the sealing body, even if it is peeled off from the side surface of the lead, it may remain in a state of protruding from the sealing body. As a result, there is a possibility that the resin burrs are likely to fall off in a subsequent process, and there is a possibility that problems such as biting of foreign matter may occur.

This indication aims at providing the semiconductor device which can suppress generation | occurrence | production of the malfunction by a resin burr | flash, and its manufacturing method in view of the said point.

According to one aspect of the present disclosure, a semiconductor device includes a lead having one side, another side opposite to the one side, and a side connecting the one side and the other side, and a seal integrated with the lead by a resin And a resin burr that protrudes from the sealing body and adheres to the lead, and adheres between the lead and the resin burr at the corner between one side and the side. A peeling prevention part is formed to prevent the resin burr from peeling off from the lead.

According to this, since the peeling prevention part which improves adhesion between the lead and the resin burr and prevents the resin burr from peeling off from the lead is formed, it is possible to suppress the occurrence of problems due to the peeling of the resin burr. it can.

According to another aspect, a method of manufacturing a semiconductor device includes: forming a lead frame having one surface, another surface opposite to the one surface, and a side surface connecting the one surface and the other surface; Forming an integrated sealing body, and removing a tie bar connecting the leads of the lead frame together with a part of the resin burr attached to the lead frame by forming the sealing body. Before forming the sealing body, in the portion of the lead frame outside the sealing body, the adhesion between the resin burr and the lead frame is increased at the corner between one surface and the side surface. Forming a peeling prevention portion for preventing the lead from peeling off from the lead frame.

According to this, the adhesion prevention between the resin burr and the lead frame is improved, and the peeling prevention part for preventing the resin burr from peeling off from the lead frame is formed. Can do.

1 is a plan view of a semiconductor device according to a first embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a cross-sectional view showing a manufacturing process of the semiconductor device shown in FIG. 1. FIG. 3B is a cross-sectional view showing the manufacturing process of the semiconductor device, following FIG. 3A; FIG. 3B is a cross-sectional view showing the manufacturing process of the semiconductor device, following FIG. 3B. FIG. 3D is a cross-sectional view showing a manufacturing step of the semiconductor device following that of FIG. 3C; FIG. 3D is a cross-sectional view showing the manufacturing process of the semiconductor device, following FIG. 3D. FIG. 3 is a plan view showing a manufacturing process of the semiconductor device shown in FIG. 1. It is sectional drawing of the semiconductor device concerning 2nd Embodiment, Comprising: It is a figure corresponded in FIG. 2 of 1st Embodiment. It is sectional drawing of the semiconductor device concerning 3rd Embodiment, Comprising: It is a figure corresponded in FIG. 2 of 1st Embodiment. FIG. 7 is a cross-sectional view showing a manufacturing step of the semiconductor device shown in FIG. 6. FIG. 7B is a cross-sectional view showing the manufacturing process of the semiconductor device, following FIG. 7A;

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
A first embodiment will be described. The semiconductor device according to the present embodiment is a resin-encapsulated semiconductor device, and includes a sealing body 1, leads 2, tie bars 3, and resin burrs 4, as shown in FIG.

The sealing body 1 is a resin sealing body including a semiconductor chip, a die pad, and the like inside. The sealing body 1 is composed of a general epoxy resin or the like, and is molded by a transfer molding method using a mold or the like.

The semiconductor device includes a plurality of leads 2, and the sealing body 1 is integrated with the plurality of leads 2 by resin. The lead 2 is for connecting a semiconductor chip included in the sealing body 1 to an external circuit, and extends from the inside to the outside of the sealing body 1.

The lead 2 is a part of a lead frame 6 to be described later. As shown in FIG. 2, the lead 2 includes one surface 21, another surface 22 opposite to the one surface 21, and a side surface 23 that connects the one surface 21 and the other surface 22. Have. The resin burr 4 is attached to the side surface 23, and the adhesiveness between the lead 2 and the resin burr 4 is enhanced at the corner portion 24 between the one surface 21 and the side surface 23, and the resin burr 4 is peeled off from the lead 2. A peeling prevention portion 25 is formed to prevent this.

In the present embodiment, the surface of the corner portion 24 is a curved inclined surface 26 that is inclined with respect to the one surface 21 and the side surface 23, and fine unevenness is formed on the inclined surface 26. The peeling prevention part 25 is comprised by the inclined surface 26 in which the unevenness | corrugation was formed. In this way, by forming irregularities on the inclined surface 26, irregularities are formed on the inclined surface 26 due to an increase in the contact area between the lead 2 and the resin burr 4 and an anchor effect due to the resin burr 4 entering the irregularities. The adhesion between the lead 2 and the resin burr 4 is improved as compared with the case where it is not performed.

As will be described later, the lead frame 6 is formed by pressing a metal plate 5. The inclined surface 26 is formed by the processing sag generated during the press processing. In the present embodiment, the inclined surface 26 has a length in the normal direction of the side surface 23 of 0.2 mm or less, and a length of the one surface 21 in the normal direction of 0.1 mm or less. By this press working, a protrusion 27 that is a processing burr that protrudes from the other surface 22 to the opposite side of the one surface 21 is formed on the other surface 22.

As will be described later, the lead 2 and the tie bar 3 are integrated as a part of the lead frame 6 before the tie bar cut is performed, and the two adjacent leads 2 are connected by the tie bar 3. A part of the tie bar 3 is removed by tie bar cutting, and the other part is left protruding from the lead 2.

As shown in FIG. 1, a resin burr 4 is formed in a region surrounded by the sealing body 1, two adjacent leads 2, and a tie bar 3. The resin burr 4 is constituted by a part of the resin used for forming the sealing body 1, protrudes from the sealing body 1 and adheres to the lead 2 and the tie bar 3. In the lead 2, the resin burr 4 is attached to the side surface 23, the surface of the corner portion 24, and the surface of the protruding portion 27.

Such a semiconductor device is manufactured by the steps shown in FIGS. 3A to 4. In the step shown in FIG. 3A, a metal plate 5 having a structure in which a metal thin film is formed on the surface of a substrate is prepared. The base material of the metal plate 5 is made of, for example, Cu, Fe, Al, Ni, an iron alloy, or the like, and the metal thin film is made of, for example, Ni, Au, Ag, or the like.

3B, a lead frame 6 having leads 2 and tie bars 3 is formed by pressing the metal plate 5. In the present embodiment, the press work is performed so that a curved inclined surface 26 is formed at the corner portion 24 between the one surface 21 and the side surface 23 of the lead 2. As a result, a protrusion 27 that is a processing burr that protrudes to the opposite side of the one surface 21 is formed at the tip of the other surface 22.

In the step shown in FIG. 3C, fine irregularities are formed on the inclined surface 26 that is the surface of the corner portion 24, thereby forming the peeling prevention portion 25. In the present embodiment, the lead frame 6 is irradiated with a pulse laser from the one surface 21 side. Specifically, the light source or the lead frame 6 is moved so that the irradiation point of the laser light moves on the one surface 21 and the inclined surface 26 while periodically blinking the light source of the laser light. Then, the surface 21 and the inclined surface are formed by a portion cut by the laser and a portion in which the metal oxide produced by the laser irradiation or the alloy of the base material of the metal plate 5 and the metal thin film material is accumulated. Unevenness is formed in 26.

After the step shown in FIG. 3C, a semiconductor chip (not shown) is mounted on the lead frame 6, the semiconductor chip is resin-sealed by a transfer molding method using a mold, etc., and the sealing body 1 integrated with the lead frame 6. Form.

At this time, a resin burr 4 is formed in a region surrounded by the sealing body 1, the lead 2 and the tie bar 3 by the resin flowing out from the mold, as shown in FIGS. The resin burr 4 adheres to the side surface 23 and the inclined surface 26 on which the unevenness is formed. Further, the resin burr 4 covers the protruding portion 27 and adheres to the end portion of the other surface 22.

In the process shown in FIG. 3E, the lead frame 6 is sheared so that a part of the tie bar 3 is punched from the one surface 21 toward the other surface 22. Specifically, the lead frame 6 and the resin burr 4 are supported by the die 7, and the cut punch 8 is applied to the one surface 21 side of the lead frame 6 to perform shearing. Although not shown in FIG. 3E, the sealing body 1 is also supported by the die 7. As a result, a part of the tie bar 3 is removed, and the two adjacent leads 2 are separated. At this time, a part of the resin burr 4 is removed together with the tie bar 3.

The remaining part of the resin burr 4 protrudes from the sealing body 1 and is attached to the lead 2 as shown in FIG. In this embodiment, the peeling prevention part 25 is formed, and the adhesiveness of the resin burr | flash 4 and the lead frame 6 is high, and also from the side in which the peeling prevention part 25 was formed among the one surface 21 and the other surface 22. Cut punch 8 enters. Thereby, peeling of the resin burr 4 left in the region surrounded by the sealing body 1 and the two adjacent leads 2 is suppressed.

After the tie bar cut, a lead cut process for separating an island (not shown) on which a semiconductor chip is mounted and the lead 2 is performed. A semiconductor device is manufactured as described above.

As described above, in the present embodiment, by forming the peeling prevention portion 25, peeling of the resin burr 4 remaining after the tie bar cut is suppressed. Therefore, it is possible to suppress the occurrence of problems due to the peeling of the resin burr 4.

(Second Embodiment)
A second embodiment will be described. In the second embodiment, the configuration of the peeling prevention unit 25 is changed with respect to the first embodiment, and the other parts are the same as those in the first embodiment. Therefore, only different parts from the first embodiment will be described. .

As shown in FIG. 5, in the present embodiment, a planar inclined surface 28 that is inclined with respect to the one surface 21 and the side surface 23 is formed in the corner portion 24, and the peeling prevention portion 25 is formed by the inclined surface 28. It is configured. The area of the inclined surface 28 is made larger than the area of the inclined surface formed by machining sagging. Such an inclined surface 28 is formed by grinding the corner portion 24 and the like after forming the sealing body 1 after performing the steps shown in FIGS. 3A and 3B as in the first embodiment. The

In this embodiment, by increasing the area of the inclined surface 28, the contact area between the lead 2 and the resin burr 4 is increased, and the peeling of the resin burr 4 is suppressed. In this embodiment, the unevenness is not formed on the one surface 21 and the inclined surface 28, but the unevenness may be formed on the inclined surface 28 as in the first embodiment. Thereby, the adhesiveness between the lead 2 and the resin burr 4 is further improved.

(Third embodiment)
A third embodiment will be described. In the third embodiment, the configuration of the peeling prevention unit 25 is changed with respect to the first embodiment, and the other parts are the same as those in the first embodiment. Therefore, only different parts from the first embodiment will be described. .

In the present embodiment, as shown in FIG. 6, a protruding portion 29 is formed at the tip of the corner portion 24 so as to protrude from the one surface 21 toward the opposite side to the other surface 22. In the present embodiment, the peeling prevention part 25 is constituted by a protrusion 29. The surface of the corner between the other surface 22 and the side surface 23 is a curved inclined surface that is inclined with respect to the other surface 22 and the side surface 23.

That is, in this embodiment, as shown in FIG. 7A, when the lead frame 6 is formed, processing sagging occurs at the corner between the other surface 22 and the side surface 23, and processing burrs occur at the corner 24. The metal plate 5 is pressed so that the protrusions 29 are formed.

Then, as shown in FIG. 7B, the lead frame 6 and the resin burr 4 are supported by the die 7 and the cut punch 8 is applied to the one surface 21 side of the lead frame 6 on which the protrusion 29 is formed, so that the tie bar 3 is one surface. Shearing is performed so that the sheet 21 is punched from 21 toward the other surface 22.

As described above, in the present embodiment in which the cut punch 8 is applied to the side on which the protruding portion 29 is formed and shearing is performed, the peeling of the resin burr 4 is suppressed by the close contact between the protruding portion 29 and the resin burr 4.

In this embodiment, no irregularities are formed on the surface 21 and the surface of the projection 29, but irregularities may be formed on the surface of the projection 29 as in the first embodiment. Thereby, the adhesiveness between the lead 2 and the resin burr 4 is further improved.

(Other embodiments)
Note that the present disclosure is not limited to the above-described embodiment, and can be modified as appropriate. Further, the above embodiments are not irrelevant to each other, and can be combined as appropriate unless the combination is clearly impossible. In each of the above-described embodiments, it is needless to say that elements constituting the embodiment are not necessarily essential unless explicitly stated as essential and clearly considered essential in principle. Yes. Further, in each of the above embodiments, when numerical values such as the number, numerical value, quantity, range, etc. of the constituent elements of the embodiment are mentioned, it is clearly limited to a specific number when clearly indicated as essential and in principle. The number is not limited to the specific number except for the case. Further, in each of the above embodiments, when referring to the shape, positional relationship, etc. of the component, etc., the shape, unless otherwise specified and in principle limited to a specific shape, positional relationship, etc. It is not limited to the positional relationship or the like.

For example, in the first embodiment, irregularities are formed in the corners 24 by laser processing, but irregularities may be formed by etching the corners 24. Further, irregularities may be formed by blasting the corners 24, and irregularities may be formed by roughening the corners 24.

Further, the corners 24 may be uneven only in the portion of the lead 2 located outside the sealing body 1. Further, the unevenness may be formed only in a part of the lead 2 where the resin burr 4 adheres. Moreover, in the said 1st Embodiment, although the unevenness | corrugation was formed in the one surface 21 and the inclined surface 26, you may form an unevenness | corrugation only in the inclined surface 26. FIG.

Claims

A semiconductor device,
A lead (2) having one surface (21), the other surface (22) opposite to the one surface, and a side surface (23) connecting the one surface and the other surface;
A sealing body (1) integrated with the lead by resin;
A resin burr (4) that is formed of a part of the resin and protrudes from the sealing body and adheres to the lead;
The corner portion (24) between the one surface and the side surface is formed with a peeling prevention portion (25) that improves the adhesion between the lead and the resin burr and prevents the resin burr from peeling off the lead. Semiconductor device.
2. The semiconductor device according to claim 1, wherein the peeling prevention portion is configured by a curved inclined surface (26) that is inclined with respect to the one surface and the side surface and has unevenness.
2. The semiconductor device according to claim 1, wherein the exfoliation preventing portion is constituted by a planar inclined surface (28) inclined with respect to the one surface and the side surface.
2. The semiconductor device according to claim 1, wherein the exfoliation preventing portion is constituted by a protruding portion (29) protruding from the one surface toward the opposite side to the other surface.
5. The semiconductor device according to claim 3, wherein unevenness is formed on a surface of the peeling prevention portion.
A method for manufacturing a semiconductor device, comprising:
Forming a lead frame (6) having one surface (21), another surface (22) opposite to the one surface, and a side surface (23) connecting the one surface and the other surface;
Forming a sealing body (1) integrated with the lead frame by resin;
Removing the tie bar (3) for connecting the lead (2) of the lead frame together with a part of the resin burr (4) attached to the lead frame by forming the sealing body,
Before forming the sealing body, the resin burr and the lead frame are formed at a corner (24) between the one surface and the side surface in a portion of the lead frame outside the sealing body. A method for manufacturing a semiconductor device, comprising: forming a peeling prevention portion (25) that enhances adhesion to the lead frame and prevents the resin burr from peeling off from the lead frame.
Part of forming the peeling prevention part is performed simultaneously with forming the lead frame,
In forming the lead frame, the lead frame is formed by pressing a metal plate (5),
The method of manufacturing a semiconductor device according to claim 6, wherein forming the peeling preventing portion includes forming irregularities on a surface of the corner portion.
The method for manufacturing a semiconductor device according to claim 6, wherein forming the peeling preventing portion includes forming a flat inclined surface (28) inclined with respect to the one surface and the side surface.
Part of forming the peeling prevention part is performed simultaneously with forming the lead frame,
By forming the lead frame, the metal plate (5) is pressed so that a protrusion (29) protruding from the one surface toward the opposite side to the other surface is formed at the corner. Forming the lead frame;
The semiconductor device manufacturing method according to claim 6, wherein in the removal, the lead frame is sheared by applying a cut punch (8) to the one surface so that the tie bar is punched from the one surface toward the other surface. Method.
10. The method for manufacturing a semiconductor device according to claim 8, wherein forming the peeling preventing portion includes forming irregularities on a surface of the corner portion.
11. The method of manufacturing a semiconductor device according to claim 7, wherein forming the unevenness irradiates the corner with a laser.
The method for manufacturing a semiconductor device according to claim 7 or 10, wherein the corners are etched by forming the irregularities.
The method of manufacturing a semiconductor device according to claim 7 or 10, wherein the corners are blasted by forming the irregularities.
The method of manufacturing a semiconductor device according to claim 7 or 10, wherein the corners are subjected to rough plating treatment by forming the irregularities.