JPH1155068A - Solid-state element device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely shield by forming a metallic film for shielding on a plane of a solid-state element which faces a nonmetallic lid which closes an opening of a package base that contains the solid-state element. SOLUTION: A chip 4 is connected with gap remaining from the bottom of a package base 1 through connecting parts such as bumps. A metallic film 10 that is formed on the rear of the chip 4 is connected to a ground pattern of the bottom of the base 1 through a bonding wire 11. A comb-shaped electrode or the like on the surface of the chip 4 is undergone facedown bonding through the connecting parts. With this structure, even if a lid 60 is not metallic, the film 10 performs a shield function, and therefore, unnecessary radiation from the chip 4 is prevented from leaking to the outside. Because of this, it reduces costs by making the nonmetallic lid 60 resin. Also, even if a lid that closes an opening of the package base is nonmetallic material, it can surely shield.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a solid-state device such as a surface acoustic wave device requiring a shield.

[0002]

2. Description of the Related Art Conventionally, when a surface acoustic wave device is manufactured, as a measure against unnecessary radiation, the entire package for encapsulating a chip (solid element) is formed of a metal material, or a material other than metal is used for a package base. Even if you use it,
Use metal for the lid that closes the opening,
Alternatively, when a lid other than a metal material is used, metal plating is applied to the rear surface of the lid to cover (shield) the periphery of the chip with metal as much as possible.

As a package material other than metal, ceramic is generally used. FIG. 5 is an assembly perspective view of a device using a conventional ceramic package, and FIG. 6 is an external perspective view after assembly. In the figure, 1 is a ceramic package base, 2 is an external electrode exposed on the outer wall of the base 1, 3 is a wire pad formed in the base 1, 4 is a chip housed in the base 1, 5 is a chip 4 and a pad. A bonding wire 6 connects to the base 3 and a metal lid 6 closing the opening of the base 1.

When the chip 4 is a surface acoustic wave device, a comb-shaped electrode 42 having a filter function is formed on the chip surface 41 as shown in FIG. In the case of FIG. 5, the chip 4 is accommodated in the base 1 with the surface 41 facing up. Since the surface acoustic wave element mechanically vibrates, when the lid 6 closes the opening of the base 1 as shown in FIG. 6, the lid 6 cannot be brought into close contact with the surface 41 of the chip 4 (it is necessary to leave a space). is there).

FIG. 7 is an assembled perspective view of a conventional surface acoustic wave device which has undergone face-down bonding, and FIG. 8 is a sectional view thereof. In face-down bonding,
The chip 4 is mounted with the front surface 41 facing down and the back surface 43 facing up. A gap is formed between the chip 4 and the base 1 at a protruding connection portion 7 such as a bump so as to be joined (adhered). A seam ring 8 made of a conductive Kovar material is interposed between the metal lid 6 and the ceramic package base 1, and is bonded by heating and pressing. This point
The same applies to the example of FIG.

[0006]

In the case of the above-mentioned ceramic package, it is necessary to connect the metal lid 6 to the ground. For this reason, the bonding between the lid 6 and the base 1 is complicated, for example, by using a conductive adhesive, which complicates the shield structure and increases the cost. For packages other than ceramic, connect the lid to ground (earth)
It is difficult to connect to the device, and a simple package structure cannot be realized. These points are problems to be solved by the present invention.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solid-state device in which the lid for closing the opening of the package base can be reliably shielded even when the lid is made of a non-metallic material, and the shield structure can be simplified.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide a solid state device, a package base for accommodating the solid state device, a non-metallic lid for closing an opening of the package base, and a lid for the solid state device. And a shielding metal film formed on a surface facing the solid-state device.

According to various embodiments of the present invention, the solid-state device is a surface acoustic wave device having a comb-shaped electrode on a surface thereof. Further, the metal film is formed on a back surface of the surface acoustic wave element. Further, the lid is formed of a resin material. Further, the lid and the package base are adhered with a non-conductive sealant. Further, the metal film is connected to the ground of the base by a bonding wire. Alternatively, the metal film is connected to the ground of the base with a conductive resin.

According to the device structure of the present invention, even if the lid is not made of metal, the metal film functions as a shield, so that unnecessary radiation from the chip can be prevented from leaking to the outside. For this reason, the lid can be made of resin and cost can be reduced.

Further, since the metal film is formed not on the lid side but on the chip side, the structure for connecting this to the ground of the base is simple. That is, grounding can be easily achieved only by a wire bonding step before the lid is closed, and there is no need to electrically connect the lid and the base. For this reason, the lid and the base can be bonded by an inexpensive sealing method of glass, resin, or the like. In other words, there is no need for costly techniques such as conventional seam welding and brazing.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to embodiments shown in the drawings. FIG. 1 is an assembled perspective view showing an embodiment of the present invention, FIG. 2 is an external perspective view thereof, and FIG.
Is a sectional view. In the drawing, 1 is a ceramic package base, 2 is an external electrode exposed on the outer wall of the base 1, 4 is a chip accommodated in the base 1 face down (front down, back up) and 10 is a chip 4 A metal film for shielding is formed on the entire back surface (43 in FIG. 9) by a method such as vapor deposition, sputtering, or plating. Reference numeral 60 denotes a non-metallic (for example, resin material) lid for closing the opening of the base 1.

As shown in FIG. 3, the chip 4 is connected to the bottom surface of the base 1 with a connection portion 7 such as a bump, with a gap left therebetween. Metal film 1 formed on the back surface of chip 4
Reference numeral 0 is connected to a ground pattern (not shown) on the bottom surface of the base 1 by a bonding wire 11. The comb-shaped electrodes and the like on the surface 41 of the chip 4 are face-down bonded by the connection portions 7.

With such a device structure, even if the lid 60 is not made of metal, the metal film 10 functions as a shield, so that unnecessary radiation from the chip 4 can be prevented from leaking to the outside. Therefore, the cost can be reduced by using the lid 60 made of resin.

Since the metal film 10 is formed not on the lid 60 but on the chip 4 side, the structure for connecting the metal film 10 to the ground of the base 1 is simple. That is, it can be easily grounded only by the wire bonding process before the lid 60 is closed,
There is no need to electrically connect the lid 60 and the base 1. For this reason, the lid 60 and the base 1 can be bonded by an inexpensive sealing method of glass, resin, or the like. In other words, there is no need for costly techniques such as conventional seam welding and brazing.

FIG. 4 is a sectional view showing another embodiment of the present invention. In this embodiment, the ground connection for the shield by the bonding wire 11 of FIG. Whether the shield ground connection is performed by wire bonding or conductive resin can be arbitrarily selected depending on manufacturing convenience.

In the above embodiment, the chip (solid-state element) 4 has been described as a surface acoustic wave element. However, the shield structure of the present invention is not limited to this. Can also be applied.

[0018]

As described above, according to the present invention, it is possible to provide a solid-state device in which the lid for closing the opening of the package base can be reliably shielded even when the lid is made of a nonmetallic material, and the shield structure can be simplified. Can be.

[Brief description of the drawings]

FIG. 1 is an assembled perspective view showing one embodiment of the present invention.

FIG. 2 is an external perspective view of the device of FIG. 1 after assembly.

FIG. 3 is a cross-sectional view of the device of FIG. 1 after assembly.

FIG. 4 is a sectional view after assembling showing another embodiment of the present invention.

FIG. 5 is an assembled perspective view showing an example of a conventional surface acoustic wave device.

6 is an external perspective view of the device of FIG. 5 after assembly.

FIG. 7 is an assembled perspective view showing another example of a conventional surface acoustic wave device.

8 is a cross-sectional view of the device of FIG. 7 after assembly.

FIG. 9 is a perspective view showing the surface acoustic wave element alone.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Package base 2 External electrode 4 Chip (solid-state element) 7 Connection part 10 Metal film 11 Bonding wire 12 Conductive resin 41 Chip surface 42 Comb-shaped electrode 43 Chip back surface 60 Nonmetallic lid

Claims (7)

[Claims] 1. A solid element, a package base accommodating the solid element, a non-metallic lid for closing an opening of the package base, and a shield formed on a surface of the solid element facing the lid. A solid-state device comprising a metal film. 2. The device according to claim 1, wherein the solid-state device is a surface acoustic wave device having a comb-shaped electrode on a surface thereof.
3. The solid-state device according to item 1. 3. The solid-state device according to claim 2, wherein the metal film is formed on a back surface of the surface acoustic wave element. 4. The solid-state device according to claim 1, wherein the lid is formed of a resin material. 5. The solid-state device according to claim 1, wherein the lid and the package base are bonded with a non-conductive sealant. 6. The solid-state device according to claim 1, wherein the metal film is connected to a ground on the base side by a bonding wire. 7. The semiconductor device according to claim 1, wherein the metal film is connected to a ground on the base side with a conductive resin.
A solid-state device according to any one of the above.