KR20180090713A - Filter module and front-end module including the same - Google Patents

Abstract

The present invention relates to a filter supporting a greater number of bands, a filter module, and a front-end module. According to an embodiment of the present invention, the filter module comprises at least two filters, each of which is responsible for at least two communication bands overlapping a bandwidth, wherein the at least two communication bands, for which any one in the at least two filters is responsible, can have different upper and lower frequencies.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a filter module and a front-

The present invention relates to a filter module and a front end module including the filter module.

Demand for small and lightweight filters, oscillators, resonant elements, and acoustic resonant mass sensors used in such devices has been rapidly increasing due to rapid development of mobile communication devices, chemical and bio devices. .

A thin film bulk acoustic resonator (FBAR) is known as a means for implementing such a compact lightweight filter, an oscillator, a resonant element, and an acoustic resonance mass sensor. Thin-film bulk acoustic resonators can be mass-produced at a minimum cost and can be implemented in a very small size. In addition, it is possible to implement a high quality factor (Q) value, which is a major characteristic of a filter, and can be used in a microwave frequency band. Particularly, a PCS (Personal Communication System) and a DCS (Digital Cordless System) There is an advantage that it can be.

Recently, as a wireless terminal supports a plurality of bands, a plurality of filters for taking up a plurality of bands are employed in wireless terminals. However, if the number of the filters responsible for the increase in the number of bands increases, the signal processing process becomes complicated and the manufacturing cost and size of the filter module become large.

It is an object of the present invention to provide a filter, a filter module and a front end module that support a larger number of bands.

A filter module according to an embodiment of the present invention includes at least two filters each responsible for at least two communication bands in which the bandwidth is overlapped, and at least two communication bands May have different upper and lower frequencies.

A filter module according to an embodiment of the present invention may include a plurality of filters, and the bands having overlapping bandwidths may be assigned to at least one filter, thereby reducing the size and manufacturing cost of the filter module.

FIG. 1A is a table provided for explaining frequencies of a transmission band and a reception band of a communication band according to an example.
FIG. 1B is a view illustrating a communication band supported by the filter module and the filter module according to an example embodiment.
2 is a view illustrating a communication band supported by a filter module according to an embodiment of the present invention.
3 is a view for explaining a filter module according to an embodiment of the present invention.
FIG. 4 is a diagram for explaining modes of a filter module according to an embodiment of the present invention. FIG.
5 is a view for explaining a filter module according to an embodiment of the present invention.
6 is a view for explaining a filter module according to an embodiment of the present invention.
7 is a view for explaining a filter module according to an embodiment of the present invention.
FIG. 8 is a diagram for explaining a method of changing the upper frequency according to the embodiment of FIG. 3; FIG.
FIG. 9 is a diagram for explaining a method of changing the upper limit frequency according to another embodiment of FIG. 3; FIG.
FIG. 10 is a diagram for explaining a method of changing the lower limit frequency according to the embodiment of FIG.
11 is a diagram for explaining a method of changing the lower limit frequency according to another embodiment of FIG.
FIG. 12 is a diagram for explaining a method of changing the lower limit frequency according to another embodiment of FIG. 3; FIG.
13 is a schematic diagram for explaining a connection method of a filter module and a switch according to an example.
14 is a cross-sectional view illustrating a filter module according to an embodiment of the present invention.

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

The embodiments may be modified in other forms or the features of the various embodiments may be combined with each other. Although the description in one embodiment is not described in another embodiment, it may be combined with the description of another embodiment unless otherwise stated or contradicted by other embodiments.

The shape and size of the elements in the accompanying drawings may be exaggerated for clarity of description, and elements denoted by the same reference numerals in the drawings may be understood as the same or similar elements. In this specification, terms such as "upper," "upper," "lower," "lower," "side," and the like are expressed with reference to the direction of the attached drawings. Actually, It will be different.

FIG. 1A is a table provided for explaining frequencies of a transmission band and a reception band of a communication band according to an example. FIG. 1B is a view illustrating a communication band supported by the filter module and the filter module according to an example embodiment.

1A may be a communication band of LTE (Long Term Evolution), and communication bands B1-B25, B65, and B66 may be transmission bands Tx and down- And a reception band Rx referred to as a down-link band.

Referring to FIG. 1B, the filter module may include a plurality of filters, and the plurality of filters may be responsible for a transmission band and a reception band of a communication band supported by the filter module.

Assuming that the filter module supports the communication bands B1, B2, B3, B4 and B25, the plurality of filters are arranged in communication bands B1_Tx, B1_Rx, B2_Tx, B2_Rx, B3_Tx, B3_Rx, B4_Tx , B4_Rx, B25_Tx, and B25_Rx.

Assuming that a plurality of filters are composed of six filters F1-F6 corresponding to a number less than the number of transmission and reception bands required for 10 filters, some of the six filters F1- A part of which is overlapped.

Referring to FIG. 1B, the filter F1 may be responsible for the communication bands B3_Tx and B4_Tx, the filter F2 may be for the communication band B3_Rx, the filter F3 may be for the communication band B1_Tx, , And B4_Rx. Further, the filter F5 can take charge of the communication bands B2_Tx and B25_Tx, and the filter F6 can take charge of the communication bands B2_Rx and B25_Rx. For example, the filters F1, F2, F3 and F4 may constitute a quadplexer and the filters F5 and F6 may constitute a duplexer.

The filter module of FIG. 1B supports a larger number of communication bands than the plurality of filters provided. However, in order to reduce the size occupied by the filter module in a wireless terminal which is becoming highly integrated and slimmed in recent years, You need to be in charge of.

2 is a view illustrating a communication band supported by a filter module according to an embodiment of the present invention.

2, assuming that the filter module supports the communication bands B1, B2, B3, B4, B25, B66, the plurality of filters employed in the filter module include communication bands B1_Tx, B1_Rx, B2_Tx, B2_Rx, B3_Tx, B3_Rx, B4_Tx, B4_Rx, B25_Tx, B25_Rx, and B66_Tx B66_Rx.

Referring to FIGS. 1A and 2, the communication bands B3_Tx, B4_Tx, and B66_Tx can overlap a part of the bandwidth, and the communication bands B3_Rx, B25_Tx, and B2_Tx can overlap a part of the bandwidth, and the communication bands B1_Tx, B25_Rx, A part of the bandwidth may be overlapped, and the bandwidths of the communication bands B1_Rx, B4_Rx, and B66_Rx may overlap.

A filter module according to an embodiment of the present invention may include a plurality of filters, and the bands having overlapping bandwidths may be assigned to at least one filter, thereby reducing the size and manufacturing cost of the filter module.

3 is a view for explaining a filter module according to an embodiment of the present invention.

According to an embodiment of the present invention, at least one of the plurality of filters employed in the filter module may be responsible for at least two communication bands where a portion of the bandwidth is overlapped.

Referring to FIGS. 1A and 3, the filter module may include a plurality of filters F1, F2, F3, and F4. The plurality of filters F1, F2, F3 and F4 may constitute one of a quadplexer and a duplexer.

Assuming that the filter module includes four filters F1, F2, F3 and F4, the filter F1 can take charge of the communication bands B3_Tx, B4_Tx, B66_Tx, in which a part of the bandwidth overlaps, and the filter F2 is part of the bandwidth The filter F3 can take charge of the communication bands B1_Tx, B25_Rx, and B2_Rx in which a part of the bandwidth is superimposed, and the filter F4 can take charge of the communication bands B3_Rx, B25_Tx and B2_Tx, , And B66_Rx. As shown in FIG. 3, when the four filters F1-F4 are responsible for bands having overlapping bandwidths, the number of filters responsible for the bands can be reduced.

According to an embodiment of the present invention, at least two communication bands in which at least one of the filter modules is responsible may have different upper and lower frequencies. In one example, the filter F2 includes a communication band B3_Rx having a lower limit frequency of 1805 [MHz] and an upper limit frequency of 1880 [MHz], B2_Tx having a lower limit frequency of 1850 [MHz] and an upper limit frequency of 1910 [MHz] And the communication band B25_Tx having the upper limit frequency of 1915 [MHz]. The filter F3 has a communication band B1_Tx having a lower limit frequency of 1920 [MHz] and an upper limit frequency of 1980 [MHz], a communication band B2_Rx having a lower limit frequency of 1930 [MHz] and an upper limit frequency of 1990 [ And a communication band B25_Rx having an upper limit frequency of 1995 [MHz] and a lower limit frequency of 1995 [MHz].

Referring to FIGS. 1A, 2 and 3, the interval between the frequency bands 1805 [MHz] to 1915 [MHz] supported by the filter F2 and the frequency band 192 [MHz] to 1995 [MHz] [MHz], and using the frequency band to which the filter F2 and the filter F3 are allocated as they are, radio frequency signals transmitted and received by the filter F2 and the filter F3 may be mixed.

The filter module according to an embodiment of the present invention may change frequency bands of different filters depending on modes when frequency bands of different filters supporting adjacent frequency bands differ from 1 [MHz] to 10 [MHz] It is possible to prevent a radio frequency signal transmitted and received by the filter from being mixed.

For example, the filter F2 may vary the assigned frequency band by adjusting the upper limit frequency in the range of 1880 [MHz] to 1915 [MHz], and the filter F3 may change the lower limit frequency in the range of 1920 [MHz] to 1930 [ So that the allocated frequency band can be varied.

FIG. 4 is a diagram for explaining modes of a filter module according to an embodiment of the present invention. FIG.

Referring to FIG. 4, the filter module may operate in a first mode and a second mode. The mode can be fixedly assigned to the filter F1 and the filter F4, and the filter F2 and the filter F3 can be adjusted in bandwidth so as to avoid interference of the frequency signal. For example, the filter F2 can be adjusted in bandwidth by changing the upper limit frequency, and the bandwidth can be adjusted by changing the lower limit frequency in the filter F3. At this time, when the upper limit frequency of the filter F2 increases and the bandwidth increases, the lower limit frequency of the filter F3 increases, and the bandwidth can be reduced. Further, when the upper limit frequency of the filter F2 decreases and the bandwidth decreases, the lower limit frequency of the filter F3 decreases, and the bandwidth can be enlarged.

Specifically, the upper frequency limit of the filter F2 increases to cover the communication bands B3_Rx, B_25Tx, and B2_Tx in the first mode (Mode 1) and the bandwidth can be expanded. In the second mode (Mode 1), the communication band B3_Rx The upper frequency can be reduced to take charge and the bandwidth can be reduced.

In addition, the filter F3 can be reduced in bandwidth by increasing the lower limit frequency so as to take charge of the communication bands B_25Rx and B2_Rx in the first mode (Mode 1), and the communication bands B1_Tx, B_25Rx, and B2_Rx in the second mode The lower frequency can be reduced to take charge and the bandwidth can be reduced.

5 is a view for explaining a filter module according to another embodiment of the present invention. Since the filter module of FIG. 5 is similar to the filter module of FIG. 3, the same or redundant description will be omitted and differences will be mainly described.

Referring to FIG. 5, the filter module may include a plurality of filters F1, F2 ', F2', F3, and F4. The plurality of filters F1, F2, F2, F3 and F4 may constitute one of a quadplexer and a duplexer. Assuming that the filter module includes five filters F1, F2, F2, F3, and F4, the filter F1 may be responsible for the communication bands B3_Tx, B4_Tx, and B66_Tx, B3_Rx, filter F2` may be responsible for B25_Tx and B2_Tx, filter F3 may be responsible for communication bands B1_Tx, B25_Rx, and B2_Rx and filter F4 may be responsible for B1_Rx, B4_Rx, and B66_Rx can do.

Comparing FIG. 3 and FIG. 5, the filter module of FIG. 5 can easily produce the filters F2 'and F2' by separating the filters for the communication bands B3_Rx, B25_Tx, and B2_Tx into two. At this time, the filters F2` and F2` operate in different modes, and the filters F2` and F2`` can avoid interference between the supported frequency bands.

6 is a view for explaining a filter module according to another embodiment of the present invention. Since the filter module of FIG. 6 is similar to the filter module of FIG. 3, the same or redundant description will be omitted and differences will be mainly described.

Referring to FIG. 6, the filter module may include a plurality of filters F1, F2, F3 ', F3', F4. The plurality of filters F1, F2, F3, F3, and F4 may constitute one of a quadplexer and a duplexer. Assuming that the filter module includes five filters F1, F2, F3 ', F3', F4, the filter F1 may be responsible for the communication bands B3_Tx, B4_Tx, and B66_Tx, and the filter F2 may be responsible for the communication bands B3_Rx , B25_Tx, and B2_Tx, filter F3` may be responsible for communication band B1_Tx, filter F3`` may be responsible for B25_Rx, and B2_Rx and filter F4 may be responsible for B1_Rx, B4_Rx, and B66_Rx can do.

Comparing FIG. 3 and FIG. 6, the filter module of FIG. 6 can easily manufacture the filters F3 'and F3' 'by separating the filters for the communication bands B1_Tx, B25_Rx, and B2_Rx into two. At this time, the filters F3` and F3` operate in different modes, and the filters F3` and F3`` can avoid interference between the supported bands.

7 is a view for explaining a filter module according to an embodiment of the present invention. Since the filter module of FIG. 7 is similar to the filter module of FIG. 3, the same or redundant description will be omitted and differences will be mainly described.

Referring to FIG. 7, the filter module may include a plurality of filters F1, F2, F2, F3, F3, and F4. The plurality of filters (F1, F2, F2, F3, F3, and F4) can form one of a quadplexer and a duplexer. Assuming that the filter module includes six filters (F1, F2`, F2``, F3`, F3`` and F4), the filter F1 can take charge of the communication bands B3_Tx, B4_Tx, and B66_Tx, F2 may be responsible for the communication band B3_Rx, the filter F2 may be responsible for B25_Tx and B2_Tx, the filter F3 may be responsible for the communication band B1_Tx, the filter F3 for B25_Rx, and B2_Rx And the filter F4 can take charge of B1_Rx, B4_Rx, and B66_Rx.

Comparing FIG. 3 and FIG. 7, the filter module of FIG. 7 can easily manufacture the filters F2 'and F2' 'by separating the filters for the communication bands B3_Rx, B25_Tx, and B2_Tx into two, It is possible to easily manufacture the filters F3 'and F3' 'by separating the filters responsible for the bands B1_Tx, B25_Rx, and B2_Rx into two.

The filters F2` and F2` operate in different modes so that the filters F2` and F2` can avoid interference between the supporting bands and the filters F3` and F3`` operate in different modes, F3` and F3` can avoid interference between the supported bands.

FIG. 8 is a diagram for explaining a method of changing the upper frequency according to the embodiment of FIG. 3; FIG. Fig. 8A is a circuit diagram showing the filter F2 in Fig. 3, and Fig. 8B is a graph showing a change in the frequency band of the filter F2.

Referring to FIG. 8A, the filter F2 according to an embodiment of the present invention may include a plurality of resonators. Here, each of the plurality of resonators may include a film bulk acoustic resonator (FBAR).

The filter F2 may include at least one series portion 10 and at least one shunt portion 20 disposed between the at least one series portion 10 and ground. The filter F2 may be formed of a filter structure of a ladder type as shown in FIG. 8, or alternatively may be formed of a filter structure of a lattice type.

At least one series unit 10 may be disposed between a signal input terminal RFin for inputting an input signal and a signal output terminal RFout for outputting an output signal and at least one shunt unit 20 is connected to at least one series And may be disposed between the connection node of the unit 10 and the signal output terminal RFout and the ground or between the connection node of the at least one series unit 10 and the signal input terminal RFin and the ground.

Although the filter F2 is shown as having one series portion 10 and one shunt portion 20 in FIG. 8A, a plurality of series portions 10 and shunt portions 20 may be provided A plurality of series parts 10 are connected in series to each other and a node between the series parts 10 to which the shunt part 20 is connected in series and a plurality of shunt parts 20, And may be disposed between the grounds. The shunt portion 20 may include at least one shunt resonator Sh and may further include a trimming inductor L disposed between the shunt resonator Sh and ground.

At least one series section 10 may include a first series resonator S1 and a second series resonator S2. The first series resonator S1 and the second series resonator S2 may be selectively operated. The first series resonator S1 and the second series resonator S2 may be connected to each other in parallel through the first switch SW1 and the second switch SW2. Specifically, the first series resonator S1 and the first switch SW1 may be connected in series with each other, and the second series resonator S2 and the second switch SW2 may be connected in series with each other. The second series resonator S2 and the second switch SW2 connected in series with the first series resonator S1 and the first switch SW1 connected to each other may be connected in parallel. The first series resonator S1, the second series resonator S2, the first switch SW1 and the second switch SW2 may be fabricated as one-chip.

The first switch SW1 and the second switch SW2 can perform switching operations in different modes. For example, in the first mode (Mode 1), the first switch SW1 may be turned on and the second switch SW2 may be turned off. In the second mode (Mode 2) The first switch SW1 is turned off and the second switch SW2 is turned on.

The first series resonator S1 and the second series resonator S2 may have different resonance frequencies and anti-resonance frequencies. For example, the first series resonator S1 and the second series resonator S2, which operate in the first mode (Mode 1) The resonance frequency may be higher than the resonance frequency of the second series resonator S2. 8 (b), in the first mode (Mode 1), the upper frequency is increased by the first series resonator S1, the bandwidth can be enlarged, and in the second mode (Mode 2) , The second series resonator S2 reduces the upper limit frequency as in the second mode (Mode 2) of Fig. 8B, and the bandwidth can be reduced.

FIG. 9 is a diagram for explaining a method of changing the upper limit frequency according to another embodiment of FIG. 3; FIG.

9 (a) and 9 (b) are circuit diagrams showing a front-end module according to an embodiment of the present invention. FIG. 9 (c) shows a change in the frequency band of the filter F2 according to an embodiment of the present invention FIG.

9A and 9B, a front end module 1000 according to an embodiment of the present invention includes an antenna 1100, a filter module 1200, a notch filter 1300, A switch 1400, and an RF integrated circuit (IC) The plurality of filters F1, F2, F3, and F4 of the filter module 1200 may correspond to the filter module of Fig. The plurality of filters F1, F2, F3 and F4 of the filter module 1200 and the notch filter 1300 can be made of a bulk acoustic resonator (FBAR), in which case the filter module 1200, the notch filter 1300 ), And the switch 1400 may be fabricated as a one-chip.

The antenna 1100 can transmit and receive a radio frequency signal and the filter module 1200 can transmit and receive a radio frequency signal received through the antenna 1100 or a radio frequency signal transmitted and received through the RF integrated circuit 1500, It is possible to perform a filtering operation to pass or remove components. The filter module 1200 may correspond to the filter module of FIG. 3 and may include a plurality of filters F1, F2, F3, and F4.

The filter F2 of the filter module 1200 may be selectively connected to the notch filter 1300 according to the mode. Thus, the notch filter 1300 can be selectively operated. The notch filter 1300 may be disposed between the filter module 1200 and the RF integrated circuit 1500 or may be disposed between the filter module 1200 and the antenna 1100 and selectively connected to the filter F2 according to the mode.

Referring to FIG. 9A, a notch filter 1300 and a switch 1400, which are connected in series with each other, may be disposed between the filter module 1200 and the RF integrated circuit 1500. The switch 1400 includes a three-terminal switch in which a first terminal is connected to the filter module 1200, a second terminal is connected to the RF integrated circuit 1500, and a third terminal is connected to the notch filter 1300 . The first terminal of the switch 1400 is connected to one of the second terminal and the third terminal to connect the filter module 1200 and the RF integrated circuit 1500 or to connect the filter module 1200 and the notch filter 1300 You can connect.

In the first mode, the switch 1400 directly connects the filter F2 of the filter module 1200 and the RF integrated circuit 1500 and in the second mode the switch 1400 connects the filter F2 of the filter module 1200 The RF integrated circuit 1500 can be connected through the notch filter 1300. [

9B, a notch filter 1300 and a switch 1400, which are connected in parallel to each other, may be disposed between the filter module 1200 and the antenna 1100. In the first mode the switch 1400 is turned on to directly connect the antenna 1100 with the filter F2 of the filter module 1200 and in the second mode the switch 1400 is turned off, The filter F2 of the module 1200 may be coupled to the antenna 1100 via the notch filter 1300 to the RF integrated circuit 1500. [

9C, when the path of the radio frequency signal through the notch filter 1300 is not formed according to the switching operation of the switch 1400 in the first mode (Mode 1), the inherent characteristic of the filter F2 A frequency band is formed according to the upper limit frequency and the lower limit frequency. However, when a path of a radio frequency signal is formed through the notch filter 1300 according to the switching operation of the switch 1400 in the second mode (Mode 2), the frequency characteristic of the notch filter 1300 causes the filter F2 Lt; / RTI > decreases, so that the bandwidth can be reduced.

FIG. 10 is a diagram for explaining a method of changing the lower limit frequency according to the embodiment of FIG. Fig. 10 (a) is a circuit diagram showing the filter F3 in Fig. 3, and Fig. 10 (b) is a graph showing a change in the frequency band of the filter F3.

Referring to FIG. 10 (a), the filter F3 according to an embodiment of the present invention may include a plurality of resonators. Here, each of the plurality of resonators may include a bulk acoustic resonator (FBAR).

The filter F3 may include at least one series portion 10 and at least one shunt portion 20 disposed between the at least one series portion 10 and ground. The filter F3 may be formed of a filter structure of a ladder type as shown in FIG. 10, or alternatively may be formed of a filter structure of a lattice type.

At least one series unit 10 may be disposed between a signal input terminal RFin for inputting an input signal and a signal output terminal RFout for outputting an output signal and at least one shunt unit 20 is connected to at least one series And may be disposed between the connection node of the unit 10 and the signal output terminal RFout and the ground or between the connection node of the at least one series unit 10 and the signal input terminal RFin and the ground.

10 (a), the filter F3 is shown as having one series portion 10 and one shunt portion 20, but a plurality of series portions 10 and shunt portions 20 may be provided A plurality of series parts 10 are connected in series to each other and a node between the series parts 10 to which the shunt part 20 is connected in series and a plurality of shunt parts 20, And may be disposed between the grounds. The series section 10 may include at least one series resonator S. [

The at least one shunt portion 20 may include a first shunt resonator Sh1 and a second shunt resonator Sh2. The first shunt resonator Sh1 and the second shunt resonator Sh2 may be selectively operated.

The first shunt resonator Sh1 and the second shunt resonator Sh2 may be connected in parallel to each other through the first switch SW1 and the second switch SW2. Specifically, the first shunt resonator Sh1 and the first switch SW1 may be connected in series with each other, the second shunt resonator Sh2 and the second switch SW2 may be connected in series with each other, The first shunt resonator Sh1 and the second shunt resonator Sh2 and the second switch SW2, which are connected in series with the first switch SW1, may be connected in parallel. The first shunt resonator Sh1 and the second shunt resonator Sh2 connected in parallel can be connected to the ground via the trimming inductor L. [ The first shunt resonator Sh1 and the second shunt resonator Sh2 are connected to ground through a separate trimming inductor L in FIG. 10 (a), but the first shunt resonator Sh1 and the second shunt resonator Sh2 are connected to ground through a separate trimming inductor L, Lt; / RTI >

The first switch SW1 and the second switch SW2 can perform switching operations in different modes. For example, in the first mode (Mode 1), the first switch SW1 is turned on and the second switch SW2 is turned off. In the second mode (Mode 2), the first switch SW1 Off operation, and the second switch SW2 can be turned on.

The first shunt resonator Sh1 and the second shunt resonator Sh2 may have different resonance frequencies and anti-resonance frequencies. For example, the first shunt resonator Sh1 operating in the first mode (Mode 1) The antiresonance frequency may be higher than the antiresonance frequency of the second shunt resonator Sh2.

10 (b), in the first mode (Mode 1), the lower frequency is increased by the first shunt resonator Sh1 so that the bandwidth can be reduced. In the second mode (Mode 2) The lower limit frequency is reduced by the second series resonator S2 as in the second mode (Mode 2) of Fig. 8 (b), and the bandwidth can be enlarged.

11 is a diagram for explaining a method of changing the lower limit frequency according to another embodiment of FIG.

11 (a) is a circuit diagram showing a filter F3 according to an embodiment of the present invention, and FIG. 11 (b) is a graph provided to explain a change in frequency band of a filter F3 according to an embodiment of the present invention .

The filter F3 according to an embodiment of the present invention may include a plurality of resonators. Here, each of the plurality of resonators may include a bulk acoustic resonator (FBAR).

The filter F3 may include at least one series portion 10 and at least one shunt portion 20 disposed between the at least one series portion 10 and ground. The filter F2 may be formed of a filter structure of a ladder type as shown in 11 (a), or alternatively may be formed of a filter structure of a lattice type.

At least one series unit 10 may be disposed between a signal input terminal RFin for inputting an input signal and a signal output terminal RFout for outputting an output signal and at least one shunt unit 20 is connected to at least one series And may be disposed between the connection node of the unit 10 and the signal output terminal RFout and the ground or between the connection node of the at least one series unit 10 and the signal input terminal RFin and the ground.

10 (a), the filter F3 is shown as having one series portion 10 and one shunt portion 20, but a plurality of series portions 10 and shunt portions 20 may be provided A plurality of series parts 10 are connected in series to each other and a node between the series parts 10 to which the shunt part 20 is connected in series and a plurality of shunt parts 20, And may be disposed between the grounds. The series section 10 may include at least one series resonator S. [

The shunt portion 20 may include a shunt resonator Sh and a transistor Tr disposed between the shunt resonator Sh and ground and additionally may include a trimming resonator Sh disposed between the shunt resonator Sh and the transistor Tr, And may further include an inductor (L).

The transistor Tr may be implemented by at least one of an N-channel field effect transistor and a P-channel field effect transistor. The transistor Tr can be turned on and off by the gate voltage Vg applied to the gate. Specifically, the transistor Tr may be turned off in the first mode (Mode 1) and turned on in the second mode (Mode 2). The transistor Tr may be equivalent to a resistor in a turn-on state, and may be equivalent to a capacitor in a turn-off state.

The antiresonance frequency of the shunt section 20 can be changed according to the turn-on and turn-off operations of the transistor Tr. Referring to FIG. 11 (b), when the transistor Tr is turned off in the first mode (Mode 1), the total capacitance of the shunt portion 20 is lowered according to the capacitance of the transistor Tr, The anti-resonance frequency of the antenna 20 is increased. In addition, when the transistor Tr is turned on in the second mode (Mode 2), the total capacitance of the shunt portion 20 becomes high, and the anti-resonance frequency of the shunt portion 20 decreases.

Therefore, when the transistor Tr is turned off in the first mode, the lower limit frequency of the filter F3 increases and the bandwidth can be reduced. When the transistor Tr is turned on in the second mode, The lower limit frequency of the filter F3 decreases, and the bandwidth can be enlarged.

FIG. 12 is a diagram for explaining a method of changing the lower limit frequency according to another embodiment of FIG. 3; FIG.

12 (a) and 12 (b) are circuit diagrams showing a front-end module according to an embodiment of the present invention.

12A and 12B, a front end module 1000 according to an embodiment of the present invention includes an antenna 1100, a filter module 1200, a notch filter 1300, A switch 1400, and an RF integrated circuit (IC) The plurality of filters F1, F2, F3, and F4 of the filter module 1200 may correspond to the filter module of Fig. The plurality of filters F1, F2, F3 and F4 of the filter module 1200 and the notch filter 1300 may be fabricated with a volume acoustic resonator (FBAR), in which case the notch filter 1300 is connected to the filter module 1200 Chip and a switch 1400 disposed between the notch filter 1300 and the notch filter 1300. [

The antenna 1100 can transmit and receive a radio frequency signal and the filter module 1200 can transmit and receive a radio frequency signal received through the antenna 1100 or a radio frequency signal transmitted and received through the RF integrated circuit 1500, It is possible to perform a filtering operation to pass and remove components. The filter module 1200 may correspond to the filter module of FIG. 3 and may include a plurality of filters F1, F2, F3, and F4.

The filter F3 of the filter module 1200 may be selectively connected to the notch filter 1300 according to the mode. Notch filter 1300 may be selectively coupled between the signal path of filter F3 and ground. The notch filter 1300 may be disposed between the filter module 1200 and the RF integrated circuit 1500 or may be disposed between the filter module 1200 and the antenna 1100 and selectively connected to the filter F3 according to the mode.

Referring to FIG. 12A, a notch filter 1300 and a switch 1400 may be disposed between the filter module 1200 and the RF integrated circuit 1500. Here, the notch filter 1300 may be connected to the ground, and the notch filter 1300 may be provided with a ground potential. The switch 1400 includes a three-terminal switch in which a first terminal is connected to the filter module 1200, a second terminal is connected to the RF integrated circuit 1500, and a third terminal is connected to the notch filter 1300 . The first terminal of the switch 1400 is connected to one of the second terminal and the third terminal to connect the filter module 1200 and the RF integrated circuit 1500 or to connect the filter module 1200 and the notch filter 1300 You can connect.

In a first mode the switch 1400 may couple the filter F3 of the filter module 1200 and the RF integrated circuit 1500 via a notch filter 1300 and in a second mode the switch 1400 may connect the filter module 1200 The filter F3 of the RF integrated circuit 1500 and the RF integrated circuit 1500 can be directly connected.

Referring to FIG. 12B, a notch filter 1300 and a switch 1400 may be disposed between the filter module 1200 and the antenna 1100. A switch 1400 is connected to the connection node of the filter F3 of the filter module 1200 and the antenna 1100 and the notch filter 1300 can be disposed between the switch 1400 and the ground.

In the first mode the switch 1400 is turned on to couple the connection node of the filter F3 of the filter module 1200 and the antenna 1100 to the notch filter 1400 and in the second mode the switch 1400 is turned on, The antenna 1100 and the filter F3 of the filter module 1200 can be directly connected.

12A and 12B, when a path of the radio frequency signal through the notch filter 1300 is not formed according to the switching operation of the switch 1400 in the second mode, A frequency band is formed according to the upper limit frequency and the lower limit frequency. However, when the path of the radio frequency signal through the notch filter 1300 is formed in accordance with the switching operation of the switch 1400 in the first mode, the lower limit frequency of the filter F3 is changed by the frequency characteristic of the notch filter 1300 So that the bandwidth can be reduced.

13 is a schematic diagram for explaining a connection method of a filter module and a switch according to an example.

As described above, the filter module and the front end module are provided with at least one switch and transistor. As shown in FIG. 13, a filter module and a switch are mounted on a printed circuit board (PCB), and are connected to each other through a wiring line provided on a printed circuit board (PCB) When connected, parasitic components generated in the wiring line cause signal loss, and the size of the switch is liable to be restricted by the area occupied by the switch on the printed circuit board (PCB).

The filter module and the front end module according to the embodiment of the present invention integrate the filter module and the switch to minimize the wiring line between the filter module and the switch can do. As a result, the signal loss caused by the parasitic component caused by the wiring line can be reduced, and the area occupied by the switch on the external substrate can be removed, thereby miniaturizing the module.

14 is a cross-sectional view illustrating a filter according to an embodiment of the present invention.

Referring to FIG. 14, a filter according to an embodiment of the present invention may include a plurality of volume acoustic resonators 100 and a cap 200. The volume acoustic resonator 100 may be a thin film bulk acoustic resonator (FBAR).

The volume acoustic resonator 100 may be realized by a laminated structure composed of a plurality of films. In Fig. 14, although two volume acoustic resonators 100 are shown as being implemented by a laminated structure, three or more volume acoustic resonators 100 may be realized by a laminated structure according to design. Adjacent volume acoustic resonators 100 may be electrically connected to each other by wiring electrodes. For example, the wiring electrodes can connect the first electrodes 140 of the adjacent bulk acoustic resonator 100 to each other and connect the second electrodes 160 of the adjacent bulk acoustic resonator 100 to each other.

The volume acoustic resonator 100 may include a substrate 110, an insulating layer 120, an air cavity 112, and a resonator 135.

The substrate 110 may be a silicon substrate and an insulating layer 120 may be formed on the substrate 110 to electrically isolate the resonator 135 from the substrate 110. The insulating layer 120 is formed on the substrate 110 by chemical vapor deposition (CVD), RF magnetron sputtering, or evaporation of one of silicon dioxide (SiO 2) and aluminum oxide (Al 2 O 2) Lt; / RTI >

The air cavity 112 may be disposed on the insulating layer 120. The air cavity 112 may be positioned below the resonator 135 so that the resonator 135 vibrates in a predetermined direction. The air cavity 112 is formed by forming a sacrificial layer pattern on the insulating layer 120, then forming a membrane 130 on the sacrificial layer pattern, and then etching and removing the sacrificial layer pattern. The membrane 130 may function as a protective oxide layer or as a protective layer protecting the substrate 110.

An etch stop layer 125 may be additionally formed between the insulating layer 120 and the air cavity 112. The etch stop layer 125 serves to protect the substrate 110 and the insulating layer 120 from the etching process and may serve as a base for depositing other layers on the etch stop layer 125.

The resonator portion 135 may include a first electrode 140, a piezoelectric layer 150, and a second electrode 160 that are sequentially stacked on the membrane 130. The common areas overlapping in the vertical direction of the first electrode 140, the piezoelectric layer 150, and the second electrode 160 may be located at the top of the air cavity 112. The first electrode 140 and the second electrode 160 may be formed of a metal such as gold (Au), titanium (Ti), tantalum (Ta), molybdenum (Mo), ruthenium (Ru), platinum (Pt), tungsten (Al), iridium (Ir), and nickel (Ni), or an alloy thereof.

The piezoelectric layer 150 is a part causing a piezoelectric effect to convert electrical energy into mechanical energy in the form of an acoustic wave and is formed of one of aluminum nitride (AlN), zinc oxide (ZnO), and lead zirconium titanium oxide (PZT; PbZrTiO) . In addition, the piezoelectric layer 150 may further include a rare earth metal. As an example, the rare earth metal may include at least one of scandium (Sc), erbium (Er), yttrium (Y), and lanthanum (La).

A seed layer for improving the crystal orientation of the piezoelectric layer 150 may be additionally disposed under the first electrode 140. The seed layer may be formed of one of aluminum nitride (AlN), zinc oxide (ZnO), and lead zirconium titanium oxide (PZT; PbZrTiO) having the same crystallinity as the piezoelectric layer 150.

The resonator portion 135 may be partitioned into an active region and a non-active region. The active region of the resonator unit 135 vibrates in a predetermined direction by a piezoelectric effect generated in the piezoelectric layer 150 when electrical energy such as a radio frequency signal is applied to the first electrode 140 and the second electrode 160. [ And corresponds to a region in which the first electrode 140, the piezoelectric layer 150, and the second electrode 160 are superimposed in the vertical direction on the upper part of the air cavity 112. The inactive region of the resonance portion 135 corresponds to a region outside the active region, which is a region which does not resonate due to the piezoelectric effect even if the first electrode 140 and the second electrode 160 are applied with electric energy.

The resonance unit 135 outputs a radio frequency signal having a specific frequency by using a piezoelectric phenomenon. Specifically, the resonance section 135 can output a radio frequency signal having a resonance frequency corresponding to the vibration caused by the piezoelectric development of the piezoelectric layer 150. [

The passivation layer 170 may be disposed on the second electrode 160 of the resonator 135 to prevent the second electrode 160 from being exposed to the outside. The passivation layer 170 may be formed of one of a silicon oxide series, a silicon nitride series, and an aluminum nitride series.

At least one via hole 113 may be formed on the lower surface of the substrate 110 to penetrate the substrate 110 in the thickness direction. The via hole 113 may penetrate through the insulating layer 120, the etch stop layer 125, and a part of the membrane 130 in the thickness direction, in addition to the substrate 110. The connection pattern 114 may be formed in the via hole 113 and the connection pattern 114 may be formed on the inner surface of the via hole 113, that is, the entire inner wall.

The connection pattern 114 can be manufactured by forming a conductive layer on the inner surface of the via hole 113. [ For example, the connection pattern 114 may be formed by depositing or applying at least one conductive metal such as gold (Au), copper (Cu), or titanium (Ti) -copper (Cu) alloy along the inner wall of the via hole 113 Can be formed by charging.

The connection pattern 114 may be connected to at least one of the first electrode 140 and the second electrode 160. For example, the connection pattern 114 may extend through at least a portion of the substrate 110, the membrane 130, the first electrode 140, and the piezoelectric layer 150 to form the first electrode 140 and the second electrode 160, As shown in FIG. The connection pattern 114 formed on the inner surface of the via hole 113 may extend to the lower surface of the substrate 110 and may be connected to the connection pad 115 provided on the lower surface of the substrate 110. In this way, the connection pattern 114 can electrically connect the first electrode 140 and the second electrode 160 to the connection pad 115. In one example, the connection pad 115 may comprise copper (Cu).

The connection pad 115 may be electrically connected to the main substrate, which may be disposed under the filter through the bump. The volume acoustic resonator 100 can perform a filtering operation of a radio frequency signal by a signal applied to the first and second electrodes 110 and 120 from the main substrate through the connection pad 115. [ The filter connected to the main substrate may form a filter module.

The cap 200 is bonded to a laminate structure forming a plurality of volume acoustic resonators 100, so that the plurality of volume acoustic resonators 100 can be protected from the external environment. The cap 200 may be packaged at the wafer level with the laminate structure.

The cap 200 may be formed in the form of a cover having an internal space in which a plurality of volume acoustic resonators 100 are accommodated. The cap 200 may be formed in a hexahedron shape having an open bottom, and thus may include an upper surface and a plurality of side surfaces.

Specifically, the cap 200 may be formed with a receiving portion at its center so as to accommodate the resonating portion 135 of the plurality of volume acoustic resonators 100, and a rim may be formed at the receiving portion so as to be joined to the bonding region of the laminated structure. As shown in FIG. The bonding region of the laminated structure may correspond to the edge of the laminated structure.

14, the cap 200 is shown to be bonded to a protective layer 170 deposited on a substrate 110. Alternatively, the cap 200 may be bonded to the protective layer 170, 125, an insulating layer 120, and a substrate 110. In this case,

The cap 200 may be bonded to the laminate structure by eutectic bonding. After the eutectic bonding agent 250 is deposited on the laminated structure, the laminated structure and the cap 200 can be bonded by pressing and heating.

The bonding agent 250 may be composed of at least one bonding layer, and eutectic bonding may be performed between the bonding layer and the cap 200. The bonding agent 250 may be provided in the bonding region of the laminate structure and the cap 200.

The bonding agent 250 may include at least three bonding layers that are sequentially stacked between the laminate structure and the cap 200. For example, the bonding agent 250 may include a first bonding layer 251, a second bonding layer 252, and a third bonding layer 253. The first bonding layer 251 may include one of gold (Au), copper (Cu), silver (Ag), platinum (Pt), nickel (Ni), and palladium (Pd) The second bonding layer 252 may include tin Sn and the third bonding layer 253 may include gold Au, copper Cu, silver Ag, platinum Pt, nickel Ni, and palladium Pd). ≪ / RTI > The first bonding layer 251 and the third bonding layer 253 may be formed of the same material to enable eutectic bonding together with the second bonding layer 252.

At least one switch 300 may be provided on the outer upper surface of the cap 200. The switch 300 shown in Fig. 14 is similar to the switch shown in Figs. 8A, 9A, 9B, 10A, 12A, Transistors. The switch 300 may be formed on a top surface of the cap 200 through a CMOS (Complementary Metal-Oxide Semiconductor) process. The switch 300 may be formed on the cap 200 before or after the bonding of the cap 200 and the laminate structure.

The cap 200 may be provided with a connection electrode 210 and a cap connection pad 220 for providing an electrical connection path of the switch 300. [ The cap 200 may include at least one connection electrode 210 and at least one connection electrode 210 may be formed to extend substantially vertically through the upper portion of the cap 200 in the thickness direction.

The cap connection pad 220 is provided along the upper surface of the cap 200 and can be connected to the switch 300 exposed to the upper portion of the cap 200. At least one connection electrode 210 is connected to the upper portion of the cap 200 And can be connected to the switch 300 through a connection pad 220 for cap extending along the outer surface.

At least one connecting electrode 210 may extend from the top of the cap 200 and be connected to at least one of the first electrode 140 and the second electrode 160. Although the connection electrode 210 is shown as being connected to the first electrode 140 and the second electrode 160 in Figure 14, the connection electrode 210 may include the first electrode 140 and the second electrode 160, And can be directly connected to the connection pattern 114 electrically connected to the first electrode 140 and the second electrode 160.

The switching operation of the switch 300 can be controlled by a signal applied from the main substrate under the filter module through the connection pattern 114 and the substrate connection pad 115. [

According to one embodiment of the present invention, since the switch 300 can operate from the main substrate disposed at the lower side in the state of being adjacent to the filter, it is possible to form a complicated circuit pattern The signal loss caused by the parasitic component can be reduced, and the substrate area efficiency relative to the parts can be increased.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

The present invention is not limited by the above-described embodiments and the accompanying drawings, but is intended to be limited only by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

10: Series section
20: Shunt part
100: volume acoustic resonator
113: via hole
114: connection pattern
115: connection pad
135:
140: first electrode
150: piezoelectric layer
160: Second electrode
210: connecting electrode
220: Connecting pad for cap
300: Switch
1000: Front End Module
1100: Antenna
1200: Filter module
1300: Notch filter
1400: Switch
1500: RF Integrated Circuit

Claims (15)

At least two filters each responsible for at least two communication bands in which the bandwidth overlaps,
Wherein at least two communication bands in one of said at least two filters have different upper frequency and lower frequency.
The method according to claim 1,
Wherein one of said at least two filters changes one of an upper limit frequency and a lower limit frequency of the allocated frequency band, and is responsible for said at least two bands.
3. The method of claim 2,
Wherein one of the at least two filters changes one of an upper frequency and a lower frequency according to a frequency band allocated to the other filter.
The method of claim 3,
Wherein a frequency band allocated to the one filter is different from a frequency band allocated to the other filter by 1 [MHz] to 10 [MHz].
3. The method of claim 2,
When one of the at least two filters has a frequency band lower than a frequency band assigned to the other filter, the one filter changes the upper frequency and the other filter changes the lower frequency module.
6. The method of claim 5,
In the first mode, the one filter increases the upper frequency limit, the other filter increases the lower limit frequency,
In a second mode, the one filter reduces the upper frequency and the other filter reduces the lower frequency.
The method according to claim 1,
Wherein the at least two filters comprise one of a quadruplexer and a duplexer. The method according to claim 1,
Wherein each of the at least two communication bands comprises a communication band of Long Term Evolution (LTE).
9. The method of claim 8,
Wherein one of the at least two filters has a first communication band having a lower frequency of 1805 MHz and an upper frequency of 1880 MHz, a lower frequency of 1850 MHz and an upper frequency of 1910 to 1915 MHz The first communication band takes charge of the second communication band,
The other filter is such that filter F3 has a third communication band having a lower limit frequency of 1920 MHz and an upper limit frequency of 1980 MHz, a lower limit frequency of 1930 MHz and an upper limit frequency of 1990 to 1995 [MHz] 4 Filter module responsible for communication band.
10. The method of claim 9,
The one filter adjusts the upper frequency of the frequency band in the range of 1880 [MHz] to 1915 [MHz], and the other filter adjusts the lower frequency of the frequency band in the range of 1920 [MHz] to 1930 [ Filter module to regulate.
An antenna for transmitting and receiving a radio frequency signal; And
A filter module for filtering a component of a specific frequency band of a radio frequency signal transmitted and received through the antenna; / RTI >
Wherein the filter module comprises at least two filters each responsible for at least two communication bands with overlapping bandwidths, wherein at least two communication bands in one of the at least two filters are at different upper frequencies and Front end module with lower frequency.
12. The method of claim 11,
Wherein one of said at least two filters changes one of an upper limit frequency and a lower limit frequency of the allocated frequency band to cover said at least two bands.
13. The method of claim 12,
Wherein one of the at least two filters changes one of an upper frequency and a lower frequency according to a frequency band allocated to the other filter.
13. The method of claim 12,
When one of the at least two filters has a frequency band lower than a frequency band assigned to the other filter, the one filter changes the upper frequency and the other filter changes the lower frequency End module.
15. The method of claim 14,
Wherein in the first mode the one filter increases the upper frequency limit and the other filter increases the lower limit frequency and in the second mode the one filter reduces the upper limit frequency, A front-end module that reduces the lower limit frequency.

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