JPH069231U - Package structure of surface acoustic wave device - Google Patents

Abstract

(57) [Summary] [Object] The present invention is a surface acoustic wave that can be configured to be small and thin by a simple process, and high frequency characteristics can be improved by reducing parasitic inductance. An object is to provide a package structure of a device. [Structure] A ceramic chip carrier 11 and a surface acoustic wave element 12 mounted on the inner surface of the chip carrier,
In a surface acoustic wave device package structure 10 including a metal lid 14 that hermetically seals an open upper portion of the chip carrier by seam welding or the like, the surface acoustic wave device is provided on an inner surface of the chip carrier. When mounted, the bumps 12a are formed in advance on the lower surface of the surface acoustic wave element, and the bonding material 15 is applied to the inner surface of the chip carrier corresponding to the bumps. Through,
The surface acoustic wave device package structure 10 is configured so that it can be electrically connected to the inner surface of the chip carrier.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is a package of a surface acoustic wave device in which a surface acoustic wave device is placed on the inner surface of a ceramic chip carrier, and an open upper part of the chip carrier is hermetically sealed by a metal lid. It is about structure.

[0002]

[Prior art]

 Conventionally, such a surface acoustic wave device has a package structure, for example, as shown in FIG. That is, referring to FIG. 2, a package structure 1 for a surface acoustic wave device includes a ceramic chip carrier 2 and a surface acoustic wave device 4 mounted on the inner surface of the chip carrier 2 and bonded by a conductive adhesive 3. And a lid 5 made of metal such as Kovar for airtightly sealing the open upper portion of the tip carrier 2 by seam welding or the like.

Here, in the surface acoustic wave device 4, the electrode portions 4 a and 4 b are bonded to each other by bonding wires 6 made of an ultrafine wire such as gold or aluminum and provided near both ends of the chip carrier 2. The pads 2a and 2b can be electrically connected.

According to the surface acoustic wave device package structure 1 configured as described above, the surface acoustic wave device 4 is mechanically fixed to the inner surface of the chip carrier 2 by the conductive adhesive 3 and is electrically connected. The chip carrier 2 can be electrically connected to the bonding pads 2a and 2b of the chip carrier 2 as well.

[0005]

[Problems to be solved by the device]

 However, in such a surface acoustic wave device package structure 1, the upper surface of the elastic surface wave device 4 is electrically connected to the bonding pads 2a and 2b of the chip carrier 2 by the bonding wires 6. Since the wire bonding work is required, the working process becomes complicated, the bonding wire 6 projects upward from the upper surface of the surface acoustic wave element 2, and the bonding pads 2a and 2b are required. Therefore, there is a problem that the internal volume of the package defined by the chip carrier 2 and the lid 5 becomes relatively large, and the package as a whole becomes large and thick.

Further, since the bonding wire 6 is routed inside the package, there is a problem that parasitic inductance is generated and desired high frequency characteristics cannot be obtained.

In view of the above points, the present invention can be configured to be small and thin by a simple process, and the high frequency characteristics can be improved by reducing the parasitic inductance. It aims to provide a package structure for surface acoustic wave devices.

[0008]

[Means for Solving the Problems]

 According to the present invention, a chip carrier made of ceramic, a surface acoustic wave element electrically connected and mechanically fixed to an electrode portion on an inner surface of the chip carrier are provided. In a surface acoustic wave device package structure including a metal lid that hermetically seals the open upper part of the chip carrier by seam welding, etc., the surface acoustic wave device is mounted on the inner surface of the chip carrier. In this case, bumps are previously formed on the lower surface of the elastic surface acoustic wave element, and a bonding material is applied to the inner surface of the chip carrier corresponding to the bumps. This is achieved by the package structure of the surface acoustic wave device, which can be electrically connected to the inner surface of the chip carrier.

[0009]

[Action]

 According to the above structure, in the surface acoustic wave element, the bump formed on the lower surface of the surface acoustic wave element can be directly attached to the inner surface of the chip carrier via the bonding material applied to the inner surface of the chip carrier. As a result, wire bonding is not required for the electrical connection, which simplifies the work process and eliminates the space in the package for wire bonding and the bonding pad. Therefore, the entire package can be made small and thin.

Further, since the bonding wire is not routed, the parasitic inductance can be reduced and the high frequency characteristic can be improved.

[0011]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. FIG. 1 shows an embodiment of a surface acoustic wave device package structure according to the present invention.

The surface acoustic wave device package 10 includes a ceramic chip carrier 11, a surface acoustic wave device 12 mounted on the inner surface of the chip carrier 11, and an open upper portion of the chip carrier 11 such as Kovar. And a lid 14 made of metal such as Kovar, which is hermetically sealed by seam welding or the like via the metal ring 13.

The above structure is similar to the conventional surface acoustic wave device package structure shown in FIG. 2. However, in the surface acoustic wave device package structure 10 according to the present invention, the chip carrier 11 is An electrode portion (not shown) is formed on the inner surface. Further, the surface acoustic wave element 12 has bumps 12a formed in advance on its lower surface, and the bonding material 15 is applied to the inner surface of the chip carrier 11 corresponding to the bumps 12a, that is, the region of the electrode portion. In this state, the surface acoustic wave element 12 is placed on the inner surface of the chip carrier 11.

As a result, the bumps 12 a can be electrically connected and mechanically fixed to the inner surface of the chip carrier 11 by so-called face down bonding via the bonding material 15. It has become. Thus, the surface acoustic wave element 12 is attached.

The surface acoustic wave device package structure 10 according to the present invention is configured as described above. The surface acoustic wave device 12 has the bumps 12a formed on the lower surface thereof without using wire bonding. It is electrically connected to the electrode portion formed on the inner surface of the chip carrier 11 via the bonding material 15.

Therefore, the space for wire bonding, that is, the space for the bonding pad and the space for accommodating the bonding wire are unnecessary, and therefore the chip carrier 11, the metal ring 13, and the metal lid 14 are used. The package can be made smaller and thinner.

Further, since the bonding wire is not routed inside the package, the parasitic inductance can be reduced, and the high frequency characteristic can be improved.

[0018]

[Effect of device]

 As described above, according to the present invention, it is possible to form a small and thin device by a simple process, and it is possible to reduce the parasitic inductance, so that high frequency characteristics can be improved. A device package structure could be provided.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a surface acoustic wave device package structure according to the present invention.

FIG. 2 is a schematic cross-sectional view showing an example of a conventional surface acoustic wave device package structure.

[Explanation of symbols]

 10 Package of Surface Acoustic Wave Element 11 Chip Carrier 12 Surface Acoustic Wave Element 12a Bump 13 Metal Ring 14 Metal Lid 15 Bonding Material

Claims (1)

[Scope of utility model registration request] 1. A ceramic chip carrier, a surface acoustic wave device mounted on an inner surface of the chip carrier, and a metal lid for hermetically sealing an open upper portion of the chip carrier by seam welding or the like. In the package structure of the surface acoustic wave device, the bumps are previously formed on the lower surface of the surface acoustic wave device when the surface acoustic wave device is mounted on the inner surface of the chip carrier. , Applying a bonding material to the inner surface of the chip carrier corresponding to the bumps, and the bumps through the bonding material,
A package structure for a surface acoustic wave device, which can be electrically connected to an inner surface of the chip carrier.