KR100401976B1 - A Surface Acoustic Wave Device - Google Patents

Abstract

The present invention relates to a surface acoustic wave device.

The technical constitution is to install the surface acoustic wave chip 13 on both sides of the substrate 11a via the insulator substrate 11b for height adjustment, and to input and output the electrode 12a to both sides of the surface acoustic wave chip 13. 12b) is installed and extended to the bottom of the substrate 11a to form a ground end, as well as conductor bumps 14a and 14b having a constant thickness above the input / output electrodes 12a and 12b. Through the above, both ends of the surface acoustic wave chip 13 are positioned above the pads 14a and 14b to connect and connect.

Accordingly, by adjusting the height of the height-adjusting insulator substrate 11b, a large power can be injected, thereby improving high power resistance characteristics.

Description

A Surface Acoustic Wave Device

The present invention relates to a surface acoustic wave device, which will be described in more detail. In the surface acoustic wave device employing a flip chip type structure, a large power can be injected to improve high power resistance characteristics. To a surface acoustic wave device.

BACKGROUND ART The known surface acoustic wave devices have been used in various wireless devices due to their small size and light weight, and are particularly used in mobile phones (mobile communication devices), contributing to the compactness and light weight of mobile phones.

In the structure of the conventional surface acoustic wave device as described above, as shown in FIG.

Oscillation or reception of the surface acoustic wave device 60 is performed by an interdigital transducer (IDT) 62 for transmission and reception formed of an Al thin film or an Al-Cu alloy thin film to which a small amount of Cu is added above the piezoelectric substrate 61. The IDT 62 has a structure in which a conductor pad 63 for connecting an electric signal from the outside is connected to the IDT 62.

In this case, in the conventional surface acoustic wave device 60 as described above, a bonding wire of Al or Au is used to connect the IDT to an external terminal.

In addition, in recent years, a bump such as Au is connected to an external terminal, and an IDT using a surface acoustic wave on the surface of a piezoelectric plate and a resonator having a reflector strip disposed on both sides of the IDT are configured to select a frequency. The function is to obtain a filter or an antenna duplexer.

On the other hand, in the conventional surface acoustic wave device as described above, since the surface of the piezoelectric plate 61 is used, the IDT 62 and the pad 63, which are electrode films formed on the surface of the piezoelectric plate 61, contain moisture. It is necessary to block such moisture and moisture by the inflow of outside air and moisture easily.

In order to improve such a disadvantage, as shown in FIG. 2, a surface acoustic wave chip 53 is installed on an upper side of a substrate 51a formed of an insulator such as ceramic or plastic, and both sides of the surface acoustic wave chip 53 are installed. In addition, the input and output electrodes 52a and 52b are laid again via the substrate 51b to extend to the bottom of the substrate 51a to form a ground end, as well as the input / output electrodes 52a ( 52b is connected to the bonding wire 54a drawn out from the chip 53, and the cover 55 is installed on the input / output electrodes 52a and 52b above the substrate 51c serving as a support. A package of the surface acoustic wave device is constituted.

In the package of the conventional surface acoustic wave device as described above, the input and output electrodes 52a via the bonding wire 54a for connecting the chip 53 and the chip 53 mounted on the substrate 51a and the chip 53. ) 52b is present in the package, and there is a problem in that the surface acoustic wave device cannot be miniaturized due to the presence of a separate large space therebetween.

On the other hand, there has been proposed a flip chip type structure that does not use the bonding wire as described above. That is, as shown in FIG. 3, the surface acoustic wave chip 43 is installed above the substrate 41a, and the input and output electrodes 42a and 42b are installed on both sides of the surface acoustic wave chip 43. Both ends of the chip 43 are positioned above the input / output electrodes 42a and 42b as well as the bottom end of the substrate 41a to form a ground end, and the conductor bumps 44a and 44b are positioned. Connected to each other, and the cover 45 is installed on the input / output electrodes 42a and 42b via a substrate 41b serving as a support, thereby configuring a package of the surface acoustic wave device.

In the conventional flip type surface acoustic wave device as described above, a separate bonding wire is not required, and the space in the package can be reduced, thereby miniaturizing the surface acoustic wave device.

However, recently, an antenna splitter using a surface acoustic wave device has been put into practical use as shown in FIG. 4, where the surface acoustic wave splitter has two surface acoustic wave filters, that is, an Rx filter for filtering a received signal from an antenna, and a transmission. A Tx filter for filtering the signal and a matching circuit for connecting the two filters are required.

In the case of the surface acoustic wave splitter, a power of a few W levels is applied. Therefore, when the flip chip type structure is adopted in a surface acoustic wave device having a relatively large power input, for example, the antenna splitter as described above, a large power may be input. There is a disadvantage in that the surface acoustic wave device is not destroyed, or the life of the sufficient surface acoustic wave device is not obtained, and the power resistance characteristics are deteriorated.

In addition, since a matching circuit element for connecting two filters is separately required, there are many problems such as the size of two surface acoustic wave chips being larger than the area of the two surface acoustic wave chips, making it difficult to miniaturize them.

SUMMARY OF THE INVENTION The present invention has been made to improve the above-mentioned problems. The object of the present invention is that even in a surface acoustic wave device employing a flip chip type structure, a large power can be introduced. The present invention provides a surface acoustic wave device capable of improving high power resistance characteristics.

1 is a perspective view of a typical surface acoustic wave device.

Figure 2 is a front sectional view of a state in which a chip is built in the conventional surface acoustic wave device.

Figure 3 is a front sectional view of a state in which a flip-type chip is built in another conventional surface acoustic wave device.

4 is a configuration diagram of an antenna splitter using a conventional surface acoustic wave device.

5 is a front sectional view of the surface acoustic wave device according to the present invention;

Figure 6 is a graph of the life test results of the surface acoustic wave device according to the present invention.

7 is a front sectional view of a surface acoustic wave device according to another embodiment of the present invention.

8 is a circuit diagram of a ladder type surface acoustic wave filter.

Explanation of symbols on the main parts of the drawings

11a, 11b ... substrate

12a, 12b input and output electrodes

13 ... elastic surface wave chip

14a, 14b ... Bump

15 ... cover

As a technical means for achieving the above object, the present invention, the surface acoustic wave chip is installed on both sides of the substrate via an insulator substrate, and the input and output electrodes are installed on the insulator substrate so that the bottom of the substrate ( In the surface acoustic wave device, the surface of the surface acoustic wave device, which is connected to the surface acoustic wave chip, is connected to the surface acoustic wave chip, and a cover is installed on the input / output electrode via a substrate serving as a support.

Both ends of the surface acoustic wave chip are positioned and connected to each other through the conductor bump having a predetermined thickness on the input / output electrode, and the distance between the input / output electrode and the surface acoustic wave chip is 0.05 mm or more. do.

In addition, according to the present invention, a surface acoustic wave chip is installed on both sides of an upper surface of the substrate via an insulator substrate, and an input and an output electrode are installed on both sides of the bottom of the surface acoustic wave chip, and the speech is extended to the bottom of the substrate. In the surface acoustic wave device connected to the surface acoustic wave chip, the cover is mounted via a substrate serving as a support on the input and output electrode,

A chip component composed of a chip inductor is installed between the surface acoustic wave chip and an input / output terminal so as to operate as a matching circuit of the surface acoustic wave filter, and terminals are disposed above and below the chip component, the bottom of the surface acoustic wave chip; Opposite to this is characterized in that a large gap between the input and output electrodes connected separately.

In addition, according to the present invention, a surface acoustic wave chip is installed on both sides of an upper surface of the substrate via an insulator substrate, and an input and an output electrode are installed on both sides of the bottom of the surface acoustic wave chip, and the speech is extended to the bottom of the substrate. In the surface acoustic wave device connected to the surface acoustic wave chip, the cover is mounted via a substrate serving as a support on the input and output electrode,

A chip component constituted by a chip capacitor is installed between the surface acoustic wave chip and an input / output terminal to operate as a matching circuit of the surface acoustic wave filter, and terminals are disposed above and below the chip component, the bottom of the surface acoustic wave chip; Opposite to this is characterized in that a large gap between the input and output electrodes connected separately.

In addition, according to the present invention, a surface acoustic wave chip is installed on both sides of an upper surface of the substrate via an insulator substrate, and an input and an output electrode are installed on both sides of the bottom of the surface acoustic wave chip, and the speech is extended to the bottom of the substrate. In the surface acoustic wave device connected to the surface acoustic wave chip, the cover is mounted via a substrate serving as a support on the input and output electrode,

A chip component composed of a chip inductor and a chip capacitor is installed between the surface acoustic wave chip and an input / output terminal so as to operate as a matching circuit of the surface acoustic wave filter. Terminals are disposed above and below the chip component, so that the surface of the surface acoustic wave chip is It is characterized in that a large gap between the bottom portion and the input and output electrodes connected to each other opposite thereto.

In addition, according to the present invention, a surface acoustic wave chip is installed on both sides of an upper surface of the substrate via an insulator substrate, and an input and an output electrode are installed on both sides of the bottom of the surface acoustic wave chip, and the speech is extended to the bottom of the substrate. In the surface acoustic wave device connected to the surface acoustic wave chip, the cover is mounted via a substrate serving as a support on the input and output electrode,

In the surface acoustic wave chip, a plurality of surface acoustic wave resonators are connected in series and connected in parallel to obtain filter characteristics. In this case, an inductor is inserted between the surface acoustic wave resonator and the ground terminal connected in parallel to the surface acoustic wave chip. The gap between the input and output electrodes is formed to be large.

In addition, according to the present invention, a surface acoustic wave chip is installed on both sides of an upper surface of the substrate via an insulator substrate, and both input and output electrodes are installed on both sides of the bottom of the surface acoustic wave chip to be extended to the bottom of the substrate. In the surface acoustic wave device connected to the surface acoustic wave chip, the cover surface is installed on the input and output electrode via a substrate serving as a support.

In the surface acoustic wave chip, a plurality of surface acoustic wave resonators are connected in series and connected in parallel to obtain filter characteristics. At this time, a capacitor is inserted between the parallel surface connected surface acoustic wave resonator and the ground terminal, and the surface acoustic wave chip is used. And a large gap between the input and output electrodes.

In addition, according to the present invention, a surface acoustic wave chip is installed on both sides of an upper surface of the substrate via an insulator substrate, and an input and an output electrode are installed on both sides of the bottom of the surface acoustic wave chip, and the speech is extended to the bottom of the substrate. In the surface acoustic wave device connected to the surface acoustic wave chip, the cover is mounted via a substrate serving as a support on the input and output electrode,

In the surface acoustic wave chip, a plurality of surface acoustic wave resonators are connected in series and connected in parallel to obtain filter characteristics. In this case, an inductor and a capacitor are inserted between the surface-connected surface acoustic wave resonator and the ground terminal, thereby providing elasticity. The gap between the surface wave chip and the input / output electrode is formed to be large.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

5 is a front sectional view of the surface acoustic wave device according to the present invention. The surface acoustic wave chip 13 is installed on both sides of the substrate 11a via the insulator substrate 11b, and is placed on the insulator substrate 11b. The output electrodes 12a and 12b are installed to extend to the bottom of the substrate 11a to form a ground end, as well as a conductor bump having a predetermined thickness above the input / output electrodes 12a and 12b. Both ends of the surface acoustic wave chip 13 are positioned and connected to each other above the bumps 14a and 14b via the 14a and 14b.

At this time, the distance d between the substrate 11a and the surface acoustic wave chip 13 is made 0.05 mm or more, more preferably 0.1 mm or more.

In addition, the cover 15 is installed above the input / output electrodes 12a and 12b through a substrate 11c serving as a support, thereby completing a package of the surface acoustic wave device.

Referring to the operation and effects of the present invention made of such a configuration as follows.

As shown in FIG. 5, the surface acoustic wave chip 13 is installed on both sides of an upper surface of the substrate 11a installed in the package of the surface acoustic wave device via the insulator substrate 11b. On the insulator substrate 11b, which is on both sides of the bottom part, the input and output electrodes 12a and 12b are installed in advance, and the input and output electrodes (12a) are extended to the bottom of the substrate 11a. 12a) and 12b are connected to the surface acoustic wave chip 13 so that the bottoms of the input and output electrodes 12a and 12b can be formed as ground terminals.

At this time, both ends of the surface acoustic wave chip 13 are positioned above the bumps 14a and 14b via the conductor bumps 14a and 14b having a predetermined thickness above the input / output electrodes 12a and 12b. The distance d between the input / output electrodes 12a and 12b and the surface acoustic wave chip 13 is made 0.05 mm or more, more preferably 0.1 mm or more.

In particular, by increasing the height of the insulator substrate 11b to increase the distance between the surface acoustic wave chip 13 and the input / output electrodes 12a, 12b, it is a device for matching circuits of surface acoustic waves or as a ladder type. type) A surface acoustic wave device which is used as an inductance connected to a parallel surface acoustic wave resonator of a surface acoustic wave filter and has a good characteristic at high electric power.

In addition, the cover 15 is installed above the input / output electrodes 12a and 12b via the substrate 11c serving as a support, thereby safely protecting the chip 13 installed in the surface acoustic wave device. It is.

Hereinafter, an embodiment of the present invention will be described.

In Fig. 1, when the distance d = 0.2 mm between the substrate 11a and the surface acoustic wave chip 13, in the two cases of d1 = 0.02 mm in Fig. 3 which is a conventional surface acoustic wave device for comparison, The electric power resistance characteristics of each surface acoustic wave device were measured.

The test conditions were an applied power of 2 W and an ambient temperature of 85 ° C., and the surface acoustic wave chip used a band pass filter of 900 MHz. In this case, the width of one IDT electrode was about 1 μm.

As a result of the above experiment, in the case of the conventional surface acoustic wave device as shown in FIG. 3, the surface acoustic wave device immediately broke down as soon as power was applied. To clarify the reason, the package was opened and the chip was observed under a microscope. As a result, it was found that the IDT could not withstand high power and was destroyed. That is, it was found that it is not possible to apply a large power to the surface acoustic wave device of the conventional flip chip.

On the other hand, in the surface acoustic wave device of FIG. 1 according to the present invention, although d = 0.3 mm, the same electric strength test was performed, but the surface acoustic wave device was not destroyed even when electric power was applied.

Next, the distance d between the surface acoustic wave chip 13 and the substrate 11a of the present invention was 0.02, 0.035, 0.05, 0.10, 0.15, 0.2, 0.25 in addition to 0.3 mm. Was performed. The results are shown in FIG.

At this time, the horizontal axis is d, the vertical axis is the life of the surface acoustic wave device.

In the graph, when the distance d between the surface acoustic wave chip 13 and the substrate 11a is 0.05 mm or more, it is confirmed that the life is suddenly long and the life is saturated at about 0.15 mm. That is, when the distance d between the surface acoustic wave chip 13 and the substrate 11a is 0.05 mm or more, a large power can be input, and it is found that, if it is 0.1 mm or more, sufficient electric power resistance is shown.

On the other hand, Figure 7 is a front sectional view of a surface acoustic wave device according to another embodiment of the present invention, as shown in Figure 4, an inductor or capacitor or inductor and capacitor which is a matching circuit element provided between the Tx filter and Rx filter Is provided in the package of the surface acoustic wave device, and a surface acoustic wave splitter excellent in power resistance is provided.

That is, in the surface acoustic wave device according to the first embodiment, the chip inductor or capacitors 16a and 16b are provided between the surface acoustic wave chip 13 and the input / output terminals 12a and 12b respectively connected thereto.

As shown in the enlarged view of FIG. 7, the terminals 17 are disposed above and below the chip inductor or capacitors 16a and 16b, and are provided between the surface acoustic wave chip 13 and the input / output electrode. At this time, in the case of a terminal where an inductor or a capacitor is unnecessary, a metal chip of the same size as that of the chip component may be inserted.

Therefore, by combining the chip inductor, the chip capacitor, or the metal chip as described above, even if there are a plurality of terminals, a matching circuit can be realized in the surface acoustic wave device freely.

That is, according to the present invention, as in the first embodiment, the chip parts having the terminal surface formed on the upper and lower sides can be inserted in all the positions of the pads 14a and 14b except for the surface acoustic wave chip 13 IDT. It is possible to increase the selection of devices. At the same time, since the distance between the chip 13 and the input / output terminals is large, a surface acoustic wave device exhibiting high electric power resistance characteristics can be obtained.

In addition, since the chip inductor and the chip capacitor of the matching circuit element are mounted inside the package, the surface acoustic wave splitter can be miniaturized.

Meanwhile, the surface acoustic wave device as described above may be applied to a ladder-type surface acoustic wave device as shown in FIG. 8.

That is, in the ladder type surface acoustic wave device as shown in Fig. 8, a plurality of surface acoustic wave resonators 81a, 81b, 81c, 82a, and 82b are connected in series (81a, 81b, 81c), and connected in parallel ( 82a and 82b to obtain filter characteristics, by inserting inductors 83a and 83b or capacitors and inductors and capacitors between the surface-connected surface acoustic wave resonators 82a and 82b and ground terminals. The bandwidth of the surface acoustic wave device is broadened.

As described above, according to the surface acoustic wave device of the present invention, even in the surface acoustic wave device employing a flip chip type structure, a gap is provided between the surface acoustic wave chip and the input / output terminal to realize a high withstand power characteristic, and between the above. In addition, by installing a chip component such as a chip inductor or a chip capacitor between the surface acoustic wave chip and the input / output terminal, excellent characteristics can be obtained.

While the invention has been shown and described with respect to specific embodiments thereof, it will be appreciated that the invention can be varied and modified without departing from the spirit or scope of the invention as set forth in the following claims. It will be appreciated that those skilled in the art can easily know.

Claims (10)

Surface acoustic wave chips 13 are mounted on both sides of the substrate 11a via an insulator substrate 11b, and input and output electrodes 12a and 12b are mounted on the insulator substrate 11b. The input and output electrodes 12a and 12b are connected to the surface acoustic wave chip 13 and are connected to the bottom of 11a and serve as a support on the input and output electrodes 12a and 12b. In the surface acoustic wave device in which the lid 15 is mounted via the substrate 11c, Both ends of the surface acoustic wave chip 13 are connected to the input and output electrodes 12a and 12b through the conductor bumps 14a and 14b having a predetermined thickness and are positioned above the bumps 14a and 14b. And a distance (d) between the input / output electrodes (12a) and the surface acoustic wave chip (13) is 0.05 mm or more. The surface acoustic wave device as claimed in claim 1, wherein a distance (d) between the surface acoustic wave chip (13) and the input / output electrodes (12a, 12b) is 0.1 mm or more. Surface acoustic wave chips 13 are installed on both sides of the substrate 11a via an insulator substrate 11b, and input and output electrodes 12a and 12b are installed on both sides of the bottom surface of the surface acoustic wave chips 13. It extends to the bottom of the substrate 11a, and the input and output electrodes 12a and 12b are connected and connected to the surface acoustic wave chip 13, and serve as a support above the input / output electrodes 12a and 12b. In the surface acoustic wave device in which the lid 15 is mounted via the substrate 11c for performing the following steps, Between the surface acoustic wave chip 13 and the input / output terminals 12a and 12b, a chip component 16a or 16b constituted by a chip inductor is installed to operate as a matching circuit of the surface acoustic wave filter, and the chip component 16a is installed. Terminals 17 are arranged above and below 16b, and a gap is formed between the bottom of the surface acoustic wave chip 13 and the input / output electrodes 12a and 12b which are respectively connected to each other. Surface acoustic wave device. Surface acoustic wave chips 13 are installed on both sides of the substrate 11a via an insulator substrate 11b, and input and output electrodes 12a and 12b are installed on both sides of the bottom surface of the surface acoustic wave chips 13. It extends to the bottom of the substrate 11a, and the input and output electrodes 12a and 12b are connected and connected to the surface acoustic wave chip 13, and serve as a support above the input / output electrodes 12a and 12b. In the surface acoustic wave device in which the lid 15 is mounted via the substrate 11c for performing the following steps, Between the surface acoustic wave chip 13 and the input / output terminals 12a and 12b, a chip component 16a or 16b constituted by a chip capacitor is installed to operate as a matching circuit of the surface acoustic wave filter, and the chip component 16a is installed. Terminals 17 are arranged above and below 16b, and a gap is formed between the bottom of the surface acoustic wave chip 13 and the input / output electrodes 12a and 12b which are respectively connected to each other. Surface acoustic wave device. Surface acoustic wave chips 13 are installed on both sides of the substrate 11a via an insulator substrate 11b, and input and output electrodes 12a and 12b are installed on both sides of the bottom surface of the surface acoustic wave chips 13. It extends to the bottom of the substrate 11a, and the input and output electrodes 12a and 12b are connected and connected to the surface acoustic wave chip 13, and serve as a support above the input / output electrodes 12a and 12b. In the surface acoustic wave device in which the lid 15 is mounted via the substrate 11c for performing the following steps, Between the surface acoustic wave chip 13 and the input / output terminals 12a and 12b, a chip component 16a and 16b constituted by a chip inductor and a chip capacitor are installed to operate as a matching circuit of the surface acoustic wave filter. Terminals 17 are disposed above and below (16a) and (16b) to form a gap between the bottom of the surface acoustic wave chip 13 and the input / output electrodes 12a and 12b which are respectively connected to each other. A surface acoustic wave device comprising one. The surface acoustic wave device as claimed in claim 3, wherein the distance d between the surface acoustic wave chip 13 and the input / output electrodes 12a and 12b is 0.05 mm or more. The surface acoustic wave device as claimed in claim 3, wherein the distance d between the surface acoustic wave chip (13) and the input / output electrodes (12a, 12b) is 0.1 mm or more. Surface acoustic wave chips 13 are installed on both sides of the substrate 11a via an insulator substrate 11b, and input and output electrodes 12a and 12b are installed on both sides of the bottom surface of the surface acoustic wave chips 13. It extends to the bottom of the substrate 11a, and the input and output electrodes 12a and 12b are connected and connected to the surface acoustic wave chip 13, and serve as a support above the input / output electrodes 12a and 12b. In the surface acoustic wave device in which the lid 15 is mounted via the substrate 11c for performing the following steps, The surface acoustic wave chip 13 connects a plurality of surface acoustic wave resonators 81a, 81b, 81c, 82a, and 82b in series (81a, 81b, 81c) and in parallel (82a, 82b) to filter characteristics. In this case, the inductors 83a and 83b are inserted between the surface acoustic wave resonators 82a and 82b and the ground terminal connected in parallel to form a gap between the surface acoustic wave chip and the input / output electrodes 12a and 12b. A surface acoustic wave device comprising one. Surface acoustic wave chips 13 are installed on both sides of the substrate 11a via an insulator substrate 11b, and input and output electrodes 12a and 12b are installed on both sides of the bottom surface of the surface acoustic wave chips 13. It extends to the bottom of the substrate 11a, and the input and output electrodes 12a and 12b are connected and connected to the surface acoustic wave chip 13, and serve as a support above the input / output electrodes 12a and 12b. In the surface acoustic wave device in which the lid 15 is mounted via the substrate 11c for performing the following steps, The surface acoustic wave chip 13 connects a plurality of surface acoustic wave resonators 81a, 81b, 81c, 82a, and 82b in series (81a, 81b, 81c) and in parallel (82a, 82b) to filter characteristics. In this case, a capacitor is inserted between the surface acoustic wave resonators 82a and 82b and the ground terminal connected in parallel to form a gap between the surface acoustic wave chip and the input / output electrodes 12a and 12b. Surface acoustic wave device. Surface acoustic wave chips 13 are installed on both sides of the substrate 11a via an insulator substrate 11b, and input and output electrodes 12a and 12b are installed on both sides of the bottom surface of the surface acoustic wave chips 13. It extends to the bottom of the substrate 11a, and the input and output electrodes 12a and 12b are connected and connected to the surface acoustic wave chip 13, and serve as a support above the input / output electrodes 12a and 12b. In the surface acoustic wave device in which the lid 15 is mounted via the substrate 11c for performing the following steps, The surface acoustic wave chip 13 connects a plurality of surface acoustic wave resonators 81a, 81b, 81c, 82a, and 82b in series (81a, 81b, 81c) and in parallel (82a, 82b) to filter characteristics. In this case, an inductor and a capacitor are inserted between the surface acoustic wave resonators 82a and 82b and the ground terminal connected in parallel to form a gap between the surface acoustic wave chip and the input / output electrodes 12a and 12b. Surface acoustic wave device.