JP2005129783A - Semiconductor resin sealing die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an expensive semiconductor resin sealing die which can eliminate the need of a flash removal step and solve problems of scratches in the contact of a substrate caused by resin flashes and a connection failure caused by the deposition of the resin flashes, and can prevent wire damage caused by the warpage of the substrate in a resin filling direction by a simple structure and high versatility, by removing resin flashes resulting from a gap between the die and the substrate. <P>SOLUTION: Approaching pins 1 each having a tilted surface in its lower end are provided to be projected at positions which are located at edges of opposing surfaces of an upper cavity block 23 adjacent to cull blocks 25, and correspond to positioning holes 71a of a substrate 70. When the substrate 70 is clamped by the upper and lower cavity blocks 23, 53, the tilted surface provided in the lower end 1a of the approaching pin 1 is pushed against the opening edge of the positioning hole 71a of the substrate 70 so that the substrate 70 is slidably moved while being pushed. Consequently, the side end face 72 of the substrate 70 is pushed against the inner side surface of the lower cavity block 53. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor resin sealing mold for sealing and molding an IC chip (hereinafter referred to as “semiconductor chip”), which is a semiconductor device such as an integrated circuit or a large-scale integrated circuit, with a substrate on which the IC chip is mounted. About. In particular, the present invention relates to a semiconductor resin sealing mold that can prevent the occurrence of resin burrs in the gap between the resin sealing mold and the substrate. The substrates in the present invention include resin substrates such as lead frames and substrates, TAB tapes, ceramic substrates and the like unless otherwise specified.

  Conventionally, as a semiconductor resin sealing mold, for example, in FIG. 5 and FIG. 6 showing the conventional example of Patent Document 1, the pin hole 8 of the semiconductor lead frame 14 is a gauge pin 7 implanted in the lower mold 21. There are some that perform positioning together. However, in order to align the pin hole 8 of the semiconductor lead frame 14 with the gauge pin 7 of the lower mold 21, it is necessary to provide a clearance between the pin hole 8 and the gauge pin 7. Positioning accuracy is low. For this reason, there is a problem that a gap is generated between the upper mold (not shown) and the semiconductor lead frame 14, and the resin enters from the gap and a resin burr is generated. Further, in Patent Document 1, in FIG. 1 to FIG. 4, either one of the contact block 5 or the contact pin 6 is provided for the lower mold 11, and the semiconductor lead frame 4 is attached to one of them. Accordingly, a mold for a semiconductor device molding machine for positioning is disclosed.

However, the mold is merely abutted and positioned, and positional deviation is likely to occur due to fine vibration after positioning, which may cause a decrease in positioning accuracy. Further, in Patent Document 1, it is necessary to provide a driving means for applying the semiconductor lead frame 4 to either the contact block 5 or the contact pin 6, and the semiconductor lead frame 4 can be automatically positioned. There wasn't. Further, in the mold 11, the resin melted from the gate 2 disposed on the opposite side of the contact block 5 or the contact pin 6 is filled in the cavity and molded. For this reason, there is a problem that the lead frame is compressed in the resin injection direction by the resin pressure and is easily warped, and the bonding wire is damaged by a wire sweep or the like.

  For example, as shown in FIGS. 1 (a) and 1 (b) of Patent Document 2, as positioning means by automatically abutting in order to eliminate the above-mentioned problems, positioning holes of the lead frame 21 are provided in the pins 6. After performing the rough positioning by inserting 22, the frame presser 25 is rotated to press the lead frame 21, and is slid to a predetermined position for positioning.

However, the molding apparatus according to Patent Document 2 can only be applied to a lead frame having high rigidity, is difficult to apply to a flexible resin substrate, and lacks versatility. Furthermore, since it is necessary to provide a special frame presser 25 in order to move the lead frame 21, there is a problem that the structure becomes complicated and the cost increases.
Japanese Utility Model Publication No. 3-73442 Japanese Patent Laid-Open No. 2-17652

  In view of the above problems, the present invention eliminates the resin burr caused by the gap between the mold and the substrate, thereby eliminating the burr processing step and scratching the substrate contact portion that has occurred due to the resin burr, This eliminates poor connection due to the adhesion of resin burrs. Furthermore, the present invention provides a semiconductor resin sealing mold that has a simple structure and high versatility while preventing damage to the bonding wire caused by the warping of the substrate that has occurred in the resin filling direction. The purpose is to do.

Means for solving the problems and effects of the invention

  In view of the above-mentioned object, a mold for semiconductor resin sealing according to the present invention includes a cavity adjacent to one of the molds in a cavity formed by holding a substrate on which a semiconductor element is mounted with a pair of molds. In a mold for semiconductor resin sealing, in which a semiconductor element is sealed by filling a resin through a runner from a cull of a block, an edge portion on a side of the cull block among opposed surfaces of the mold adjacent to the cull block At the position corresponding to the positioning hole of the substrate, and a protruding pin having an inclined surface at a free end, and when the substrate is clamped by a pair of the molds, A structure in which the inclined surface provided at the free end of the substrate is brought into pressure contact with the opening edge of the positioning hole of the substrate, and the substrate is slid while being pressed, whereby the side end surface of the substrate is pressed against the inner surface of the cavity. age A. In the present invention, the cavity is not limited to a space sealed with resin, but refers to an internal space including a space for storing a substrate or the like.

  Alternatively, the semiconductor resin sealing mold according to the present invention is a cavity block formed by holding a substrate on which a semiconductor element is mounted with a lower mold and an upper mold, and is adjacent to the upper mold. In a semiconductor resin sealing mold for sealing the semiconductor element by filling a resin through a runner from a cull, on the edge of the upper block adjacent to the cull block on the edge on the calblock side When a clamping pin having an inclined surface is projected at a lower end at a position corresponding to the positioning hole of the substrate and the substrate is clamped by the upper and lower molds, The inclined surface provided at the lower end is brought into pressure contact with the opening edge portion of the positioning hole of the substrate, and the substrate is slid while being pressed, whereby the side end surface of the substrate is pressed against the inner surface of the cavity. May

According to the present invention, no gap is formed between the side end surface of the substrate and the inner side surface of the cavity, and no resin burr is generated due to the intrusion of the resin. This eliminates the need for a resin burr removal process and prevents connection defects due to scratches on the substrate contact portion and resin burr caused by the resin burr.
In addition, according to the present invention, since one end side of the substrate is positioned by the approach pin arranged in the vicinity of the cull block, the substrate is not warped as in the conventional example, and damage to the bonding wire due to wire sweep or the like can be prevented.
Furthermore, it is possible to position the substrate with high positioning accuracy simply by projecting a pin toward a predetermined position of one mold, and to obtain a semiconductor resin sealing mold with a simple structure and high versatility. effective.

As an embodiment of the present invention, a close pin may be implanted in a mold via a cylindrical elastic member.
According to the present embodiment, the contact pin is easily elastically deformed in a direction orthogonal to the axis, and the degree of freedom of adjustment is increased, and breakage of the contact pin due to an excessive load can be prevented.

As other embodiment, you may form the slit which divides the lower end part of a close-up pin into two.
According to this embodiment, one of the two divided lower ends of the contact pin is more easily elastically deformed, and the substrate is slid to a predetermined position, so that the degree of freedom of adjustment is increased and an excessive load is applied. Breakage of the contact pin can be prevented.

In another embodiment, the slit may be filled with an elastic material.
According to the present embodiment, there is no possibility that a resin or the like enters the slit, and there is an effect that breakage of the contact pin or defective molding can be prevented in advance.

Embodiments of a semiconductor resin sealing mold according to the present invention will be described with reference to the accompanying drawings of FIGS.
As shown in FIGS. 1 to 6, the mold for semiconductor resin sealing according to the first embodiment is roughly an upper mold set 10 incorporating an upper mold chess 20 and a lower mold incorporating a lower mold chess 50. It consists of a mold set 30.

  In the upper mold set 10, side blocks 12 and 12 are arranged on both side edges of the lower surface of the upper mold base plate 11. And the guide protrusions 13 and 13 are each provided in the inward surface which the said side block 12 opposes, and it has the structure which can carry out the slide fitting of the upper type | mold chess 20 mentioned later from the side.

The upper chess 20 has a pin plate (not shown) and an ejector plate 26 sequentially stacked at the center of the upper surface of the holder base plate 21, and chess space blocks 27 and 27 are arranged on both sides of the upper chess 20. A groove 28 is formed. On the other hand, as shown in FIG. 3, the holder base plate 21 has a cull block 25 provided with a cull 24 at the center of its lower surface and upper mold cavity blocks 23, 23 provided with cavities 22 on both sides thereof. Each is arranged. As shown in FIGS. 3 and 5, close pins 1 are planted at a predetermined pitch at the edge adjacent to the cull block 25 in the lower surface of the upper mold cavity block 23. The outer pin 1 has a substantially frustoconical outer peripheral surface, and the cross section is cut into a substantially trapezoidal shape (FIG. 4). And the narrow part of the said lower end part 1a is facing the cull block 25 (FIG. 5). The cavity 22 and the cull 24 communicate with each other via a runner 26 and a gate 27 (FIG. 2). In general, the cull block and the cavity are composed of parts that can be separated in consideration of the maintenance of the mold, but there is no particular problem even if they are integrated.

  As shown in FIG. 1, the lower mold set 30 is obtained by assembling a lower chess base plate 33 via space blocks 32 and 32 arranged on both side edges of the upper surface of the lower mold base plate 31. The lower chess base plate 33 has side blocks 36 and 36 disposed on both side edges of the upper surface thereof, and an end block 37 disposed on one end portion of the upper surface thereof. Further, guide ridges 36a and 36a for slidingly fitting a lower chess 50, which will be described later, are formed on the opposing inner side surfaces of the side blocks 36 and 36, respectively. Further, a plunger isobaric cylinder block 34 is arranged in the center between the chess base plates 32 and 32. As shown in FIG. 3, the plunger isobaric cylinder block 34 can reciprocate in the axial direction through a through hole 56 a provided in a center block 56 of the lower chess 50 described later. .

The lower mold chess 50 have guide grooves 51 and 51 (the inner side guide grooves 51 are not shown) formed on opposite side surfaces, respectively, and a center block 56 is disposed in the center thereof. Through holes 56a are formed in the center block 56 at a predetermined pitch, and the plunger 35 can extrude the molding resin tablet 60 inserted into the through holes 56a (FIG. 3). Further, on both sides of the center block 56, a lower mold cavity block 53 for forming a substrate mounting surface 52 is disposed. A positioning pin 54 for rough positioning is projected from the upper surface of the lower mold cavity block 53 to the edge adjacent to the center block 56 (FIG. 3).
In FIG. 1, a lower mold set block 50 a for positioning the upper mold set block 20 a of the upper mold chess 20 on the lower mold chess 50 is illustrated.

Next, the sealing process by the resin sealing mold apparatus comprising the above-described components will be described.
As shown in FIG. 3, a positioning hole 71 of a resin substrate 70 (FIG. 2) on which a semiconductor chip is mounted is loosely fitted on a positioning pin 54 protruding from the lower mold cavity block 53, and is disposed on the mounting surface 52. The solid tablet 60 is inserted into the through hole 56a. Then, the lower mold chess 50 are pushed up by pushing up the lower mold set 30 via a drive mechanism (not shown). Thereby, the upper mold cavity block 23 of the upper mold chess 20 and the lower mold cavity block 53 of the lower mold chess 50 clamp the substrate 70.

  In particular, when the lower mold chess 50 incorporated in the lower mold set 30 is raised, the narrow lower end 1a, which is the inclined surface of the shifting pin 1, immediately before clamping, is formed on the substrate 70 as shown in FIGS. 5A to 5C. The substrate 70 is slid and moved toward the center block 56 while pressing the substrate 70 with its component force while pressing and contacting the opening edge of the positioning hole 71a. Therefore, the lower end 1 a is lowered to the pin hole 57 while the side end surface 72 of the substrate 70 is pressed against the outer surface of the center block 56. Next, the lower mold block 53 and the upper mold block 23 clamp the substrate 70, and the through hole 56a, the cull 24, the runner 26, the gate 27, and the cavity 22 communicate with each other.

Then, by raising the plunger 35 of the isobaric cylinder block 34, the solid tablet 60 is heated and compressed to form a fluid, and the molten resin is injected into the cavity 22 to seal and mold the substrate 70. Next, the entire lower mold set 30 is lowered and the mold is opened. Further, the plunger 35 of the isobaric cylinder block 34 is raised again to lift the molded product from the lower mold cavity block 53, and then the molded product is gripped by a carrier (not shown) and the product is taken out.
Note that a relief (not shown) may be formed in a part of the lower mold set 30, and the molded product may be taken out only by the carrier without raising the plunger 35. Further, an ejector mechanism that is normally used may be provided and ejected.

  According to the present embodiment, no gap is generated between the substrate 70, the center block 56, and the lower mold block 53, and no resin burr is generated. This eliminates the need to remove the resin burrs, and can prevent defects such as scratches on the substrate contact portions due to the resin burrs and poor connection due to adhesion of the resin burrs. Further, the substrate 70 is positioned by the contact pin 1 disposed in the vicinity of the cull block 25 and the edge portion of the substrate 70 located on the opposite side of the contact pin 1 is not restrained. For this reason, even if the molten resin flows into the cavity 22, only a simple compressive force in the thickness direction is applied to the substrate 70, and no wire sweep or the like occurs in the bonding wires of the semiconductor chip. There is an advantage that the bonding wire is not damaged.

  As shown in FIG. 7, in the second embodiment, the lower end of the upper chess space block 23 has an edge adjacent to the cull block 25, and the pin 2 is placed at a predetermined pitch via the cylindrical elastic member 3. This is the case of planting in As for the said approach pin 2, the outer peripheral surface of the lower end part 2a is a substantially truncated cone shape. For this reason, as shown in FIG. 8, even when the substrate 70 is displaced from the predetermined position by the distance β, the lower end portion 2a of the shift pin 2 is located at the opening edge of the positioning hole 71a of the substrate 70. The substrate 70 is slid while being pressed and pressed against the substrate 70 by the component force. Therefore, the side end surface 72 of the substrate 70 is in pressure contact with the inner surface of the center block 56. The other parts are the same as those in the first embodiment, and the same parts are denoted by the same reference numerals and the description thereof is omitted.

In addition, as a cylindrical elastic member concerning this embodiment, what consists of silicon | silicone, urethane, a polyfluorinated ethylene (brand name Teflon) can be considered, for example.
Of course, the shape of the lower end 2a may be the same as that of the lower end 1a of the first embodiment.

In the third embodiment, as shown in FIGS. 9 to 11, the slit 5 is provided on the lower end side of the shifting pin 4 and divided into two, thereby forming the lower end portions 4a and 4b and further elastically deforming. This is the case. For this reason, as shown in FIG. 11, even when the substrate 70 is displaced from the predetermined position by the distance Γ, the substrate 70 slides in the same manner as in the first embodiment.
That is, as shown in FIGS. 10A to 10C, immediately before clamping, one lower end portion 4a of the contact pin 4 is in pressure contact with the opening edge of the positioning hole 70a of the substrate 70, and the substrate 70 is pressed by the component force. The center block 56 is slid by a distance Γ. Then, the lower end portions 4 a and 4 b are fitted into the pin holes 57 while the side end surface 72 of the substrate 70 is pressed against the inner surface of the center block 56. The other parts are the same as those in the first embodiment, and the same parts are denoted by the same reference numerals and the description thereof is omitted.

  In the present embodiment, an elastic material such as silicon rubber may be filled in order to prevent a problem caused by resin or the like entering the slit 5. Moreover, the lower end part 5b is not necessarily required and may be cut off.

  The mold for semiconductor resin sealing according to the present invention can be applied not only to a substrate on which a semiconductor is mounted but also to a normal substrate.

It is a disassembled perspective view which shows 1st Embodiment of the metal mold | die for semiconductor resin sealing concerning this invention. It is a top view which shows arrangement | positioning of the board | substrate concerning 1st Embodiment. It is sectional drawing which shows the metal mold | die for semiconductor sealing of 1st Embodiment. 4A, 4B, and 4C are a front view, a right side view, and a partial plan view showing a closing pin according to the first embodiment. 5A, 5B and 5C are explanatory diagrams of a resin sealing process showing before, during and after mold clamping according to the first embodiment. It is explanatory drawing which shows the positional relationship of the approach pin concerning 1st Embodiment, and the positioning hole of a board | substrate. 7A, 7B and 7C are explanatory diagrams of a resin sealing process showing before, during and after mold clamping according to the second embodiment. It is explanatory drawing which shows the positional relationship of the approach pin concerning 2nd Embodiment, and the positioning hole of a board | substrate. 9A, 9B, and 9C are a front view, a right side view, and a partial plan view showing a closing pin according to a third embodiment. 10A, 10B, and 10C are explanatory diagrams of a resin sealing process showing before, during, and after mold clamping according to the third embodiment. It is explanatory drawing which shows the positional relationship of the approach pin concerning 3rd Embodiment, and the positioning hole of a board | substrate.

Explanation of symbols

1, 2, 4: Leading pins 1a, 2a, 4a, 4b: Lower end portion 3: Cylindrical elastic member 5: Slit 10: Upper mold set 20: Upper mold chess 22: Cavity 23: Upper mold cavity block 24: Cull 25: Cull block 30: Upper mold set 50: Lower mold chess 52: Mounting surface 53: Lower mold cavity block 54: Positioning pin 56: Center block 56a: Through hole 57: Pin hole 60: Tablet 70: Substrate 71: Positioning hole 71a: Positioning hole 72: Side end face

Claims (5)

A cavity formed by holding a substrate on which a semiconductor element is mounted with a pair of molds is filled with resin from a cull of a cull block adjacent to one of the molds via a runner to seal the semiconductor element. In the mold for semiconductor resin sealing to stop,
Of the opposing surfaces of the mold adjacent to the cull block, a close-up pin having an inclined surface at a free end is located at the edge on the cull block side and at a position corresponding to the positioning hole of the substrate. When projecting and clamping the substrate with the pair of molds, the inclined surface provided at the free end of the leading pin is brought into pressure contact with the opening edge of the positioning hole of the substrate while pressing the substrate A mold for semiconductor resin sealing, wherein the side end surface of the substrate is brought into pressure contact with the inner side surface of the cavity by sliding. Filling a cavity formed by holding a substrate on which a semiconductor element is mounted with a lower mold and an upper mold from a cull block adjacent to the upper mold through a runner, the resin is filled. In the semiconductor resin sealing mold to be sealed,
Among the opposing surfaces of the upper mold adjacent to the cull block, a close pin having an inclined surface at the lower end is located at the edge on the cull block side and at a position corresponding to the positioning hole of the substrate. When projecting and clamping the substrate with the upper and lower molds, the inclined surface provided at the lower end portion of the leading pin is pressed against the opening edge of the positioning hole of the substrate while pressing the substrate A mold for semiconductor resin sealing, wherein the side end surface of the substrate is brought into pressure contact with the inner side surface of the cavity by sliding.   The mold for semiconductor resin sealing according to claim 1 or 2, wherein the close-up pin is implanted in the mold through a cylindrical elastic member.   The semiconductor resin sealing mold according to any one of claims 1 to 3, further comprising a slit that divides the lower end portion of the closing pin into two. The mold for semiconductor resin sealing according to claim 4, wherein an elastic material is filled in the slit.

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