CN111430856B

CN111430856B - Compact enhanced coupling type three-dimensional hairpin filter

Info

Publication number: CN111430856B
Application number: CN202010245405.7A
Authority: CN
Inventors: 王凤娟; 柯磊; 余宁梅
Original assignee: Xian University of Technology
Current assignee: Yibo Communication Equipment Group Co ltd
Priority date: 2020-03-31
Filing date: 2020-03-31
Publication date: 2021-10-22
Anticipated expiration: 2040-03-31
Also published as: CN111430856A

Abstract

The invention discloses a compact reinforced coupling type three-dimensional hairpin filter which comprises a filter circuit structure made of copper layer RDLs, wherein each layer of RDLs adopts a plane structure of a crossed U-shaped resonant cavity, and TSV is adopted between the adjacent two layers of filter circuit structures for signal transmission. The filter circuit structures of each layer correspond to each other, and each layer of RDL comprises a plurality of part couplings. The first part of the coupling of the plurality of parts is input tap coupling, the last part of the coupling is output tap coupling, and the coupling of the middle part is resonance cavity coupling. The coupling coefficient of the three-dimensional hairpin filter adopting the TSV technology is multiplied, and the performance of the filter is optimized. In summary, the compact enhanced coupling type three-dimensional hairpin filter adopting the TSV technology has the advantages that the compact physical size realizes the miniaturization of the filter, and the multiplied coupling coefficient improves the performance of the filter compared with the traditional hairpin filter.

Description

Compact enhanced coupling type three-dimensional hairpin filter

Technical Field

The invention belongs to the technical field of filter manufacturing, and particularly relates to a compact enhanced coupling type three-dimensional hairpin filter.

Background

Due to the rapid development of modern wireless communication technology, low-loss, small-size, light-weight and low-cost filters form an important market, which creates a good opportunity for the development of microwave filters. The microstrip line type filter is a filter form widely adopted in the microwave filter due to the advantages of small size, easy photoetching processing, high precision, low cost, easy integration, large working frequency range and the like. The microstrip filter is usually in the form of hairpin-type, parallel coupled line, comb line, interdigital and microstrip elliptic function filter.

Compared with a parallel coupling line filter structure, the hairpin type band-pass filter has a compact circuit structure and is widely applied to occasions with strict size requirements; compared with a comb line and interdigital filter, the hairpin type band-pass filter does not need via hole grounding, and eliminates errors introduced by via holes; compared with a microstrip elliptic function filter, the hairpin type band-pass filter has a simpler design process. Therefore, the hairpin type band-pass filter has better electrical property, thereby having good application prospect in the design of a microwave planar circuit.

Today, the shrinking of physical dimensions in planar circuit processes has reached a bottleneck, creating an irreparable conflict with the development of moore's law. Three-dimensional integration technology is a technology that has emerged in order to go beyond moore's law. The silicon through hole is used as a key technology in a three-dimensional integrated circuit, the whole interconnection length can be shortened, and the integration level of a system is improved.

Disclosure of Invention

The invention provides a compact enhanced coupling type three-dimensional hairpin filter, which is used for realizing the compactness of the traditional hairpin filter and the enhancement of the coupling coefficient, thereby realizing the reduction of the physical size and the optimization of the filtering effect.

The technical problem to be solved by the invention is realized by the following technical scheme:

a compact reinforced coupling type three-dimensional hairpin filter comprises a filter circuit structure made of copper layer RDLs, wherein each layer of RDLs adopts a plane structure of a crossed U-shaped resonant cavity, and signal transmission is carried out between two adjacent layers of filter circuit structures by TSVs.

The present invention is also characterized in that,

the filter circuit structures of each layer correspond to each other, and each layer of RDL comprises a plurality of part couplings.

The first part of the coupling of the plurality of parts is input tap coupling, the last part of the coupling is output tap coupling, and the coupling of the middle part is resonance cavity coupling.

Each resonant cavity comprises three communicated microstrip lines, each line is provided with a plurality of silicon through holes, and each line is communicated with the three lines of the corresponding resonant cavity through the silicon through holes.

One end of the RDL manufacturing filter coupling structure is provided with an input tap feeder, and the other end of the RDL manufacturing filter coupling structure is provided with an output tap feeder.

Several sections are coupled into six sections.

Compared with the prior art, the invention has the beneficial effects that:

the invention discloses a compact enhanced coupling type hairpin filter. The coupling coefficient of the three-dimensional hairpin filter adopting the TSV technology is multiplied, and the performance of the filter is optimized. In summary, the compact enhanced coupling type three-dimensional hairpin filter adopting the TSV technology has the advantages that the compact physical size realizes the miniaturization of the filter, and the multiplied coupling coefficient improves the performance of the filter compared with the traditional hairpin filter.

Drawings

Fig. 1 is a top view of a compact enhanced coupled three-dimensional hairpin filter of the invention.

Fig. 2 is a front view of a compact enhanced coupled three-dimensional hairpin filter of the invention.

Fig. 3 is a left side view of the compact enhanced coupled three-dimensional hairpin filter of the invention.

In the figure: 1. an upper layer RDL inputs a tap feeder; 2. an upper RDL first resonant cavity; 3. an upper RDL second resonant cavity; 4. an upper RDL third resonant cavity; 5. an upper RDL fourth resonant cavity; 6. an upper RDL fifth resonant cavity; 7. an upper layer RDL outputs a tap feeder; 8. the first pair of TSVs are used for connecting two arms of a first resonant cavity of the upper and lower layers of RDLs; 9. the first pair of TSVs are used for connecting two arms of the second resonant cavity of the upper and lower layers of RDLs; 10. the first pair of TSVs is used for connecting two arms of a third resonant cavity of the upper and lower layers of RDLs; 11. the first pair of TSVs is used for connecting two arms of a fourth resonant cavity of the upper and lower layers of RDLs; 12. the first pair of TSVs is used for connecting two arms of a fifth resonant cavity of the upper and lower layers of RDLs; 13. a lower RDL inputs a tap feeder; 14. a lower RDL outputs a tap feeder; 15. a first through silicon via for connecting a first arm of a first resonant cavity of the upper and lower RDL layers; 16. a second through silicon via for connecting the first arm of the first resonant cavity of the upper and lower RDL layers; 17. a third through silicon via for connecting the first arm of the first resonant cavity of the upper and lower RDL layers; 18. a fourth through silicon via for connecting the first arm of the first resonant cavity of the upper and lower RDL layers; 19. a fifth through silicon via for connecting the first arm of the first resonant cavity of the upper and lower RDL layers; 20. and the sixth silicon through hole is used for connecting the first arm of the first resonant cavity of the upper RDL layer and the lower RDL layer.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Several sections are coupled into six sections.

A compact reinforced coupling type three-dimensional hairpin filter is characterized in that an upper copper layer RDL and a lower copper layer RDL are adopted to manufacture a filter circuit structure, and TSV is adopted between the upper layer RDL and the lower layer RDL to transmit signals, so that the doubling of a coupling coefficient is realized. The upper and lower copper layers RDL are identical, and each layer RDL comprises six parts of coupling. As shown in fig. 1-3, the first section coupling is an input tap coupling and is comprised of an input tap feed and a first resonator. The second part is coupled between the resonant cavities and consists of a first resonant cavity and a second resonant cavity. The third part is coupled between resonant cavities and consists of a second resonant cavity and a third resonant cavity. The fourth part is coupling between resonant cavities and consists of a third resonant cavity and a fourth resonant cavity. The fifth part is coupled between the resonant cavities and consists of a fourth resonant cavity and a fifth resonant cavity. The sixth part is output tap coupling and consists of a fifth resonant cavity and an output tap feeder. And the RDLs at the upper layer and the lower layer are communicated by using TSV. The five resonant cavities respectively comprise three communicated microstrip lines, namely two arms are connected with each other. RDL layer physical size: the length of the input and output tap microstrip line is 200um, the width is 61um, the distance between the input and output tap microstrip line and the bottom edge of the first arm of the first resonant cavity and the bottom edge of the second arm of the fifth resonant cavity is 160um, namely the tap height is 160 um. The length of two arms of the five resonant cavities is 550um, and the width is 50 um. The length of the microstrip line between two arms of the five resonant cavities is 600um, and the width of the microstrip line is 10 um. The distance between the second arm of the first resonant cavity and the first arm of the second resonant cavity is 82 um. The distance between the second arm of the second resonant cavity and the first arm of the third resonant cavity is 113 um. The distance between the second arm of the third resonant cavity and the first arm of the fourth resonant cavity is 82 um. The distance between the second arm of the fourth resonant cavity and the first arm of the fifth resonant cavity is 113 um. Physical size of through silicon via: copper post diameter 50um, oxide layer thickness 5um, copper post length 80 um.

The traditional hairpin filter is a plane structure formed by cascading U-shaped resonant cavities. The "U" resonator and the inverted "U" resonator represent microstrip line implementations of the LC circuit portions in series and the LC circuit portions in parallel. The invention is a compact enhanced coupling type hairpin filter adopting TSV technology. First, the compact implementation is achieved by using a planar structure of intersecting "U" resonators for each layer of RDL. The coupling coefficient matrix and the arm length are unchanged. And the transverse dimension of the device is reduced, and the area of the device is greatly reduced, namely the device is compact in size. Second, the enhanced coupling is reflected in a multiplication of the coupling coefficient of the six components. The coupling coefficient of each layer of RDL includes: the coupling coefficient of the first part coupling is 7.56, the coupling coefficient of the second part coupling is 0.10, the coupling coefficient of the third part coupling is 0.07, the coupling coefficient of the fourth part coupling is 0.07, the coupling coefficient of the fifth part coupling is 0.10, and the coupling coefficient of the sixth part coupling is 7.56. The coupling coefficient of the three-dimensional hairpin filter is the sum of the upper and lower layers of RDL coupling coefficients. The coupling coefficient of the first most part coupling is 15.12, the coupling coefficient of the second part coupling is 0.20, the coupling coefficient of the third part coupling is 0.14, the coupling coefficient of the fourth part coupling is 0.14, the coupling coefficient of the fifth part coupling is 0.20, and the coupling coefficient of the sixth part coupling is 15.12. Therefore, the coupling coefficient of the three-dimensional hairpin filter adopting the TSV technology is multiplied, and the performance of the filter is optimized. In summary, the compact enhanced coupling type three-dimensional hairpin filter adopting the TSV technology has the advantages that the compact physical size realizes the miniaturization of the filter, and the multiplied coupling coefficient improves the performance of the filter compared with the traditional hairpin filter. The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention and the equivalent alternatives or modifications according to the technical solution and the inventive concept of the present invention within the technical scope of the present invention.

Claims

1. A compact enhanced coupling type three-dimensional hairpin filter is characterized by comprising filter circuit structures made of upper and lower copper layer redistribution layers (RDLs), wherein each layer of RDLs adopts a planar structure of a mutually crossed U-shaped resonant cavity, and Through Silicon Vias (TSVs) are adopted between the adjacent two layers of filter circuit structures for signal transmission;

the circuit structures of all layers of the filters are completely the same and correspond to each other, and each layer of the redistribution layer (RDL) comprises a plurality of parts which are coupled;

each U-shaped resonant cavity comprises three communicated microstrip lines which are respectively connected between two arms, the arms of two adjacent U-shaped resonant cavities mutually penetrate into the resonant cavities, each line is provided with a plurality of silicon through holes, and each line is connected with the corresponding line of the corresponding U-shaped resonant cavity through the silicon through holes.

2. The compact enhanced coupling type three-dimensional hairpin filter according to claim 1, wherein a first part of the couplings is an input tap coupling, a last part of the couplings is an output tap coupling, and all the couplings in the middle part are resonator-to-resonator couplings.

3. The compact enhanced coupling type three-dimensional hairpin filter according to claim 1, wherein the RDL-made filter coupling structure is provided with an input tap feed line at one end and an output tap feed line at the other end.

4. The compact enhanced coupling three-dimensional hairpin filter according to claim 1, wherein the plurality of sections are coupled in six sections.