JP2018046046A - Hollow package and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow package that is high in productivity and that can be manufactured at low cost, in a semiconductor device that has a package structure having a SAW filter element and a MEMS element in a hollow structure, and to provide a method of manufacturing the same.SOLUTION: In a hollow package having a hollow structure, a step part 4 is formed on an upper surface of a wall part 3 surrounding a chip mounting part 1. By bonding the step part 4 with a lid 7 under a decompressed atmosphere, and then, bonding as a whole by a pressure difference at the time when returned to a normal pressure, the hollow package is formed collectively.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hollow package and a manufacturing method thereof, and more particularly to a hollow package having a hollow element surface for mounting a SAW filter element, a MEMS element, and the like, and a manufacturing method thereof.

  In recent years, electronic components in which a SAW (Surface Acoustic Wave) filter element, a MEMS (Micro Electro Mechanical Systems) element, and the like are mounted on a mounting substrate are widely used. These electronic components are devices that require mechanical operation on the surface of an element (chip), and a hollow package in which the chip surface is hollowed is used.

  In this type of hollow package, a ceramic has been conventionally used as a mounting substrate. For example, after mounting a chip on a substrate on which a recess is formed, the recess of the substrate is sealed with low melting glass, or after mounting the chip on a plate-shaped ceramic substrate, a metal lid is attached. A soldering method or the like is employed (for example, Patent Document 1).

  On the other hand, a chip is formed on a silicon substrate to be a mounting substrate, and another silicon substrate or the like is processed into a shape having a concave portion and a joint portion suitable as a lid, and these silicon substrates are bonded together, and thereafter There has also been proposed a method of manufacturing electronic components having a hollow package in a batch by singulation (for example, Patent Document 2).

  In addition, the applicant of the present application, after connecting the chip to the substrate by wire bonding, applies silicone that can be removed in a later process to the chip surface, transfer molding using a sealing resin, and then removing the silicone to open the chip surface. (Patent Document 3). Specifically, as shown in FIG. 10, after the IC chip 20 is mounted on the substrate 21, the IC chip 20 and the substrate 21 are electrically connected by the wire 22, and a silicone resin is dropped on the surface of the IC chip 20. By doing so, the silicone lump 23 solidified into a gel is formed. Next, the substrate 21 is set in a mold in a state where the upper surface of the silicone lump 23 is in contact with the inner surface of the mold, and the cavity is filled with the sealing resin 24 and molded (FIG. 10a). Thereafter, as shown in FIG. 10B, the silicone lump 23 is removed by a dissolving agent to form a cavity 25 that exposes a part of the surface of the IC chip 20. Furthermore, a hollow package can be formed by bonding the lid 26 on the upper surface of the sealing resin 24 so as to cover the cavity 25 (FIG. 10c).

JP 2014-241495 A JP 2012-84681 A JP 2009-267272 A

  By the way, in the conventionally proposed method for manufacturing a hollow package, the metal lids must be individually joined one by one, which is a low productivity method.

  On the other hand, the method of bonding the silicon substrate that becomes the mounting substrate and the silicon substrate that becomes the lid into individual pieces is to process the silicon substrate that becomes the lid into a concave shape or to form a bonding member for bonding the silicon substrates together. There is a problem that the manufacturing process becomes complicated. In addition, there is a problem that a special apparatus is required when bonding silicon substrates together.

  Furthermore, in the method of forming a hollow structure by forming a silicone lump to form a hollow structure and removing it with a solvent, there is a problem that the manufacturing process becomes complicated and it is difficult to realize downsizing. there were.

  The present invention solves the above-described problems and provides a hollow package and a method for manufacturing the same that can achieve both productivity improvement and cost reduction when forming a hollow package on which chips such as SAW filter elements and MEMS elements are mounted. Objective.

  In order to achieve the above object, an invention according to claim 1 of the present application relates to a hollow package in which a chip is mounted inside a package, a chip mounting portion, a wall portion surrounding the chip mounting portion, and both sides on the upper surface of the wall portion. An adhesive comprising a concave stepped portion communicating with the surface side and a lid bonded to the upper surface of the wall portion, the lid being filled between the stepped portion and upper surface of the wall portion and the lid The layer is bonded to the wall portion without any gap.

  According to a second aspect of the present invention, in a method for manufacturing a hollow package in which a chip is mounted inside a package, a plurality of chip mounting portions, a wall portion surrounding each of the chip mounting portions, and both side surfaces on the upper surface of the wall portion A step of preparing a collective substrate having a concave step portion communicating with the chip, a step of mounting the chip on each of the chip mounting portions, and a sheet-like lid on the wall portion via an adhesive layer The adhesive is made of the adhesive by placing the adhesive layer between the stepped portion and the upper surface of the wall portion and the lid, and mounting the stepped portion and the upper surface of the wall portion. A step of bonding without gaps by layers and a step of cutting and removing a part of the lid, the wall portion, and the aggregate substrate using a dicing saw.

  In order to achieve the above object, the invention according to claim 3 of the present application is the method for manufacturing a hollow package according to claim 2, wherein the lid and the stepped portion and the upper surface of the wall portion are bonded to each other with the adhesive layer without a gap. The step of matching is carried out by placing the lid with a sheet-like adhesive on the wall portion under a reduced pressure atmosphere, and pasting the lid without gaps on at least the outer peripheral portion of the collective substrate as normal pressure, and the pressure difference Thus, the adhesive layer is inserted between the stepped portion and the upper surface of the wall portion surrounded by the outer peripheral portion and the lid.

  According to the hollow package and the manufacturing method thereof of the present invention, a collective substrate is used and a sheet-like lid is bonded to the upper surface of the wall portion so as to be separated into pieces, so that a plurality of electronic components can be easily formed at the same time. It becomes. Particularly in the present invention, since the upper surface of the wall portion is provided with a concave stepped portion that communicates with both side surfaces, when mounting the lid on the upper surface of the wall portion in a reduced pressure atmosphere, each chip mounting portion is recessed. The pressure is equal throughout the collective substrate through the stepped portion of the shape. Therefore, the lid can be bonded to the upper surface of the wall portion with good uniformity over the entire assembly substrate when the atmospheric pressure atmosphere is thereafter set.

  Here, by bonding the lid in a state where the pressure is reduced to a predetermined pressure set in advance, and then setting it to normal pressure, it becomes possible to allow the adhesive formed on the lid to enter the concave stepped portion with good controllability, There is an advantage that an airtight structure can be easily formed.

  In particular, even when warpage or the like occurs in the collective substrate, an airtight structure can be reliably formed, and both productivity improvement and cost reduction can be achieved.

It is explanatory drawing of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of the hollow package of this invention. It is explanatory drawing of the manufacturing method of this kind of conventional hollow package.

  The hollow package of the present invention includes a concave stepped portion on the upper surface of the wall portion surrounding the chip mounting portion, and an adhesive enters the stepped portion. An adhesive is also formed on the upper surface of the wall, and a lid is attached via this adhesive layer. Hereinafter, examples of the present invention will be described in detail according to the manufacturing process.

  First, embodiments of the present invention will be described in detail. FIG. 1 is an explanatory view of a hollow package according to the present invention. FIG. 1 (a) is a plan view showing a state where a lid and an adhesive layer are removed, and FIG. 1 (b) is a cross-sectional view taken along the XY plane of FIG. In the figure, a cross-sectional view of the state where the lid and the adhesive layer are attached is shown, and FIG. 1C is a side view thereof. As shown in FIGS. 1A and 1B, a chip 2 such as a SAW device or a MEMS device is mounted on the chip mounting portion 1. In the present embodiment, the chip mounting portion 1 is formed of a lead frame, and the chip mounting portion 1 is formed with hanging pins extending in four directions. A wall portion 3 is formed around the chip mounting portion 1 on which the chip 2 is mounted. On the upper surface of the wall portion 3, a step portion 4 that communicates with both side surfaces of the wall portion 3 is formed. In the example shown in FIG. 1A, the step portion 4 is formed at one place on each of the four side wall portions 3 formed around the chip mounting portion 1. As an example, the stepped portion 4 can have a width of about 0.2 mm and a depth of about 0.05 mm. The chip 2 mounted on the chip mounting portion 1 is connected to the lead 6 by connecting means such as a wire 5. Between the chip mounting portion 1 and the lead 6 and between the lead 6 and the adjacent lead 6, for example, an epoxy resin is filled, and the space between the leads is fixed.

  The surface side of the chip 2 mounted on the chip mounting portion 1 has a hollow structure, and a lid 7 is attached so as to face the chip mounting portion 1. The lid 7 has a structure attached to the upper surface of the wall portion 3 via an adhesive layer 8. In this embodiment, as shown in FIGS. 1B and 1C, the adhesive layer 8 enters the stepped portion 4 to form an airtight structure.

  The step portion 4 having a characteristic structure in the hollow package of the present invention is an important constituent requirement when following the method for manufacturing a hollow package of the present invention described below.

  Next, the manufacturing method of the hollow package of this invention is demonstrated. 2A is a partial plan view of the collective substrate 10 with the back tape 9 bonded to the back surface, and FIG. 2B is a cross-sectional view taken along the XY plane of FIG. As shown in FIG. 2, the collective substrate 10 has a shape in which a plurality of chip mounting portions 1, leads 6, and the like described in FIG. 1 are continuous, and an outer peripheral portion 11 is formed around the periphery.

  The collective substrate 10 uses a lead frame generally used in the manufacturing process of a semiconductor device, and simultaneously seals between the chip mounting portion 1 and the lead 6 or between the lead 6 and the adjacent lead 6, The wall portion 3 and the outer peripheral portion 11 are formed. This sealing resin is performed, for example, by setting a lead frame in a transfer mold and pouring and curing the resin. Specifically, the sealing resin does not flow into the region where the chip mounting portion 1 is to be formed, the region where the wall portion 3 is to be formed, between the chip mounting portion 1 and the lead 6, between the lead 6 and the adjacent lead 6, The transfer mold is designed so that the sealing resin flows into the outer peripheral portion 11. In addition, by forming the male side of the mold into a convex shape in the region where the stepped portion 4 is to be formed, the wall portion 3 made of a sealing resin and its wall as shown in FIG. A stepped portion 4 is formed on the upper surface by cutting it into a concave shape. As an example, the width of the upper surface of the wall portion 3 is desirably 0.4 mm or more because the lid 7 needs to be sufficiently bonded to the adhesive layer 8. The height of the wall 3 and the outer peripheral part 11 is preferably 0.15 mm higher than the height of the chip 2. Further, the back tape 9 attached to the chip mounting portion 1 and the back surface of the lead 6 is peeled off after being collectively sealed.

  The step portion 4 is formed to communicate with both side surfaces of the wall portion 3 and the outer peripheral portion 11. With such a structure, when the lid 7 is bonded to the outer peripheral portion 11 of the collective substrate 10 through the adhesive layer 8 without any gap in a reduced pressure atmosphere in the manufacturing process described later, each chip mounting portion 1 is It communicates with the level | step-difference part 4 on the wall part 3, and can maintain each space in a uniform pressure reduction state. In the example shown in FIG. 2, the stepped portion 4 is formed on four surfaces constituting the chip mounting portion 1, but it is not always necessary to form on the four surfaces.

  Moreover, the shape of the step part 4 in the outer peripheral part 11 is not necessarily limited to the above-mentioned shape, and may have another shape. Specifically, for example, the step portion 4 formed on the outer peripheral portion 11 may be formed on the upper surface of the outer peripheral portion 11 so as not to communicate with both side surfaces. With such a structure, when the lid 7 is bonded to the outer peripheral portion 11 of the collective substrate 10 in a reduced pressure atmosphere in the manufacturing process described later, the upper surface of the outer peripheral portion 11 is changed from the reduced pressure atmosphere to the normal pressure. It is possible to prevent the adhesive layer 8 from flowing out from the stepped portion 4 formed in the above. On the other hand, each chip mounting part 1 communicates with the step part 4 on the wall part 3, and each space can be maintained in a uniform reduced pressure state.

  Next, the chip 2 is mounted on the chip mounting portion 1 of the collective substrate 10, and the electrodes formed on the chip 2 and the leads 6 of the collective substrate 10 are electrically connected by wires 5 (FIG. 3). The following description will be made using a cross-sectional view of the collective substrate 10 in a state where three chip mounting portions 1 are connected. At this time, the capillary used in the wire bonder device uses a deep access or the like having a thin tip to avoid contact with the wall portion 3 made of the sealing resin, so that a chip close to the area of the chip mounting portion 1 can be obtained. It can be installed.

  Next, the lid 7 in which the adhesive layer 8 is formed on one surface and the dicing sheet 12 is bonded to the opposite surface is prepared. Further, the lid 7 can be made of an organic-inorganic thin film such as a glass epoxy resin or a metal film made of an Fe—Ni alloy. The adhesive layer 8 may be a thermosetting resin in addition to an epoxy resin thermosetting resin. For example, a phenol resin or a silicone resin may be used. The thickness of the adhesive layer 8 only needs to be able to sufficiently enter the stepped portion 4, and more preferably about 0.05 mm thicker than the depth of the stepped portion 4. As the dicing sheet 12, a sheet generally used in the manufacturing process of a semiconductor device can be used. For example, a substrate made of vinyl chloride (PVC) or polyolefin (PO) can be used. Further, the dicing sheet 12 is held in advance by a ring-shaped jig and then bonded to one side of the lid 7. The lid 7 having the above-described configuration is prepared in advance so as to cover the collective substrate 10 and not to be smaller than the outer peripheral portion 11, and above the wall portion 3 and the outer peripheral portion 11 through the adhesive layer 8 in the decompression device 13. The lid 7 is placed on. At this time, the collective substrate 10 is placed on the hot plate 14 (FIG. 4).

Next, the outer peripheral part 11 and the lid 7 are bonded together. Specifically, the air in the decompression device 13 is first expelled to create a decompressed atmosphere (about 1.0 × 10 ⁴ Pa). Further, as the adhesive for the adhesive layer 8, a resin having low fluidity is selected. As an example, A2029 manufactured by Nagase ChemteX Corporation can be used. At this time, the hot plate 14 is heated to 80 ° C. to heat the collective substrate 10, the adhesive layer 8 and the whole. When the adhesive layer 8 is heated and softened, the adhesive layer 8 is brought into close contact with the upper surface of the outer peripheral portion 11 while being pressure-bonded using the roller 15 from above the dicing sheet 12. Layer 8 enters. Further, the adhesive layer 8 may use an adhesive selected from other adhesives. In that case, the temperature of the hot plate 14 may be changed to, for example, 150 ° C. according to the softening temperature of the adhesive to be used. In this step, since the stepped portion 4 communicates with both side surfaces on the upper surface of the outer peripheral portion 11, the inside of the decompression device 13 is heated after the heating of the collective substrate 10, the adhesive layer 8 and the whole by the hot plate 14. A reduced-pressure atmosphere may be used.

  On the other hand, when the stepped portion 4 on the upper surface of the outer peripheral portion 11 described above is formed partway without communicating to both side surfaces, the pressure reducing device 13 is first set in a reduced pressure atmosphere, and then the adhesive layer 8 is removed. After the lid 7 is placed on the wall 3 and the outer peripheral portion 11, the adhesive layer 8 may be inserted into the stepped portion 4 and bonded together while being pressure-bonded using the roller 15.

  After pressing the outer peripheral portion 11 on one side (right side of the drawing) on one side of the collective substrate 10 using the roller 15, the roller 15 is moved in the left direction in FIG. 5 to press the outer peripheral portion 11 (FIGS. 5 and 6). ). Moreover, it crimps | bonds also to the other outer peripheral part 11 which is not shown in figure, and the outer peripheral part 11 (four sides) and the lid 7 are bonded together without gap. At this time, there may be a portion where the adhesive layer 8 does not enter the stepped portion 4 on the upper surface of the wall portion 3 due to warpage of the collective substrate 10 or the like (FIG. 6). The purpose in this step is to bond the outer peripheral portion 11 and the lid 7 with the adhesive layer 8 in the decompression device 13 to bring the hollow structure portion in the collective substrate 10 into a decompressed state. There is no restriction | limiting in the structure of the level | step-difference part 4 in the part 11. FIG.

  Next, the atmosphere is put into the decompression device 13 to return to normal pressure (FIG. 7). At this time, each hollow structure in the collective substrate 10 is in a reduced pressure state because the outer peripheral portion 11 and the lid 7 are adhered by the adhesive layer 8. Moreover, since each hollow structure is connected by the level | step-difference part 4 of the upper surface of the wall part 3, the pressure of each hollow structure is the same. When returning to normal pressure in such a state, the lid 7 is pushed into the hollow structure side due to the pressure difference because the outside of the hollow structure is at normal pressure. If it does in this way, even if it uses the roller 15 by the curvature etc. of the aggregate substrate 10, the level difference part 4 and the lid 7 which were formed in the upper surface of the wall part 3 or the wall part 3 cannot be stuck using the adhesive layer 8 Also, since the adhesive layer 8 is softened by heating, the lid 7 and the stepped portion 4 can be bonded by a pressure difference. At this time, the length of the stepped portion 4 formed on the upper surface of the outer peripheral portion 11 may be set such that the adhesive of the adhesive layer 8 is not washed away to the hollow structure side due to a pressure difference from the outside of the package.

  Further, when the stepped portion 4 described above is formed partway without being communicated to both side surfaces of the outer peripheral portion 11, the stepped portion 4 does not exist on the outer surface of the outer peripheral portion 11. The adhesive of 8 is not pushed away to the hollow structure side. Thereafter, the collective substrate 10 is taken out from the decompression device 13 (FIG. 8).

  Next, using a dicing apparatus, the dicing saw 16 is rotated and cut into pieces while applying water (FIG. 9). That is, with the dicing sheet 12 side down, the collective substrate 10, the outer peripheral portion 11 or the wall portion 3, the adhesive layer 8, and the lid 7 are cut using a dicing saw 16 from the opposite side of the dicing sheet 12. A singulated hollow package can be obtained.

  As mentioned above, although the Example of this invention was described, it cannot be overemphasized that this invention is not limited to these. For example, the step portion 4 is provided on the upper surface of the wall portion 3 and the outer peripheral portion 11 at one place, but two or more steps may be provided. Or it may be on the corner | angular which each crosses instead of the upper surface of the wall part 3 or the outer peripheral part 11. FIG. Moreover, although the shape of the stepped portion 4 is a concave shape, it may be a convex shape, a U shape or a V shape.

1: chip mounting part,
2: Chip,
3: Wall part
4: Stepped part,
5: Wire,
6: Lead,
7: Lid,
8: Adhesive layer
9: Back tape,
10: collective board,
11: outer periphery,
12: dicing sheet,
13: decompression device,
14: Hot plate
15: Roller,
16: Dicing saw.

Claims (3)

In the hollow package where the chip is mounted inside the package,
A chip mounting portion; a wall portion surrounding the chip mounting portion; a concave stepped portion communicating with both side surfaces on the upper surface of the wall portion; and a lid bonded to the upper surface of the wall portion. Is a hollow package that is bonded to the wall portion without any gap by an adhesive layer filled between the step portion and the upper surface of the wall portion and the lid. In the manufacturing method of the hollow package in which the chip is mounted inside the package,
Preparing a collective substrate comprising a plurality of chip mounting portions, a wall portion surrounding each of the chip mounting portions, and a concave stepped portion communicating with both side surfaces on the upper surface of the wall portion;
Mounting the chip on each of the chip mounting portions;
By placing a sheet-like lid on the wall portion through an adhesive layer, and filling the adhesive layer made of the adhesive between the stepped portion and the upper surface of the wall portion and the lid, The step of bonding the lid and the stepped portion and the upper surface of the wall portion without gaps with the adhesive layer;
And a step of cutting and removing the lid, the wall portion, and a part of the collective substrate into pieces by using a dicing saw.   3. The method for manufacturing a hollow package according to claim 2, wherein the step of bonding the lid, the stepped portion and the upper surface of the wall portion without gaps with the adhesive layer is performed by adhering a sheet on the wall portion in a reduced pressure atmosphere. Steps and top surfaces of the wall part surrounded by the outer peripheral part due to the pressure difference after placing the lid with the agent and pasting the lid without gaps on at least the outer peripheral part of the collective substrate A method for producing a hollow package, wherein the adhesive layer is filled between the lid and the lid.

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