Bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon process

Abstract

The application discloses a band-pass filter with high roll-off coefficient and wide out-band suppression based on high-resistance silicon technology. On the basis of a mixed topology structure of a conventional third-order high-pass filter and a third-order band-pass filter, by introducing cross-capacitance coupling, and by comprehensively considering device size and deleting some components which are not sensitive to performance, the purposes of wide out-band suppression capability, high roll-off coefficient and miniaturization are achieved; upper sideband transmission zero points are mainly composed of parallel inductance-capacitance resonance units, lower sideband transmission zero points are mainly composed of cross-coupling capacitors, and the remaining two transmission zero points of the upper sideband are mainly caused by inductive or capacitive coupling of a compact structure, so that the wide out-band suppression performance is achieved. The IPD band-pass filter has the characteristics of compact structure, small in-band insertion loss, wide out-band suppression performance and high roll-off coefficient, can be easily integrated with other radio frequency modules into a module, and realizes good communication of a 5G frequency band of 3.3-4.2 GHz.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of radio frequency / microwave / millimeter wave, and particularly relates to a bandpass filter with high roll-off coefficient and wide out-of-band suppression based on high-resistance silicon technology. BACKGROUND

[0002] With the continuous development of 5G technology, in order to meet the requirements of high transmission rate, high information capacity, low delay and high quality of signal transmission, higher requirements are put forward for the performance and indexes of various devices of the 5G system. As a key device in the radio frequency link, the performance of the filter directly determines the normal operation of the entire system. In some miniaturized wireless products, such as mobile phones, WIFI, Bluetooth and other electronic devices, due to the limitation of small size, it is necessary to ensure that the size of the device is getting smaller and smaller without affecting the performance of the device. The ordinary PCB board-level circuit is not suitable because of its large size, and it is urgent to develop and design small-sized devices with compact structure. At present, many miniaturization technical solutions have been proposed, such as LTCC devices, which are widely used in base stations and other equipment because of their small size; integrated passive devices IPD technology is widely used in WIFI, mobile phones and other wireless products because of its small size and area. The substrate material used in IPD devices can be divided into silicon, high-resistance silicon, gallium arsenide, glass and the like. Considering the dielectric loss, resistivity and price, the design adopts high-resistance silicon as the substrate of the integrated passive device process. The topology structure of the IPD bandpass filter generally adopts the ordinary topology structure of the bandpass filter, the structure combining the topology of the low-pass filter and the high-pass filter, and other topologies. These topologies have certain problems, mainly that the out-of-band suppression level of the designed filter is not enough, and the roll-off coefficient is also poor. In order to solve this product pain point, the application adopts the topology structure combining the three-order high-pass filter and the three-order bandpass filter based on the IPD process of high-resistance silicon, and in order to reduce the size of the device, the capacitors and inductors which are not sensitive to performance indexes are deleted and cross-zero points are introduced to further improve the out-of-band suppression. The designed IPD bandpass filter works in the frequency band of 3.3-4.2GHz, and has high roll-off coefficient and wide out-of-band suppression performance. SUMMARY

[0003] The IPD band-pass filter of the application covers 3.3-4.2 GHz frequency band, has high roll-off coefficient and wide out-of-band suppression performance. The filter is based on the topology structure of high-pass filter and band-pass filter, and in consideration of the size of the device, some inductors and capacitors which are not sensitive to the performance are appropriately deleted, and cross-zero capacitor is introduced to further improve the out-of-band suppression performance. The designed IPD filter has small in-band loss, excellent roll-off coefficient, wide out-of-band suppression capability, compact overall structure and is easy to integrate in the radio frequency module.

[0004] The technical scheme adopted by the application is as follows:

[0005] The IPD filter of high resistance silicon process has high roll-off coefficient and wide out-of-band suppression performance, and the filter comprises a dielectric stack (0) and a filter circuit structure formed on the dielectric stack (0).

[0006] The filter circuit structure is provided with a ground (0_2) at the periphery; the input port is composed of ground-signal-ground, and mainly comprises a first ground (3_2), a first signal input end (1_2) and a second ground (4_2); the output port is composed of ground-signal-ground, and mainly comprises a third ground (5_2), a second signal output end (2_2) and a fourth ground (6_2); the first signal end (1_2) is connected to the first input port of the first capacitor (7_2) through a transmission line, the first output port of the first capacitor (7_2) is connected to the input end of the second capacitor (8_2) through a transmission line, and the second output port of the first capacitor (7_2) is connected to the input end of the first inductor (13_2) through a transmission line, the output end of the first inductor (13_2) is connected to the input end of the third capacitor (9_2) through a transmission line, and the output end of the third capacitor (9_2) is connected to the ground (0_2); the output end of the second capacitor (8_2) is connected to the input end of the second inductor (14_2) through a transmission line, the first output end of the second inductor (14_2) is connected to the input end of the fourth inductor (16_2) through a transmission line, the output end of the fourth inductor (16_2) is connected to the input end of the fifth capacitor (11_2) through a transmission line, and the output port of the fifth capacitor (11_2) is connected to the output signal port (2_2) through a transmission line; the second output end of the second inductor (14_2) is connected to the input end of the third inductor (15_2) through a transmission line, and the output end of the third inductor (15_2) is connected to the ground (0_2); the third output end of the second inductor (14_2) is connected to the input end of the fourth capacitor (10_2) through a transmission line, and the output port of the fourth capacitor (10_2) is connected to the ground (0_2); the third output port of the first capacitor (7_2) is connected to the input port of the sixth capacitor (12_2) through a transmission line, and the output port of the sixth capacitor (12_2) is connected to the output port of the second inductor (14_2) through a transmission line.

[0007] The first capacitor (7_2), the sixth capacitor (12_2), the third capacitor (9_2), and the first inductor (13_2) constitute a three-order high-pass filter; the second capacitor (8_2), the fourth capacitor (10_2), the fifth capacitor (11_2), the second inductor (14_2), the third inductor (15_2), and the fourth inductor (16_2) constitute a three-order band-pass filter, wherein the second capacitor (8_2) is shared by the high-pass filter and the band-pass filter; the upper sideband out-of-band transmission zero point tuning element and the lower sideband out-of-band transmission zero point tuning element constitute out-of-band transmission zero point tuning elements, the upper sideband out-of-band transmission zero point tuning element is controlled by a parallel resonance unit, and the parallel resonance unit includes the first inductor (13_2) and the third capacitor (9_2); the lower sideband out-of-band transmission zero point tuning element is controlled by a cross element sixth capacitor (12_2) and is simultaneously affected by the second capacitor (8_2) and the second inductor (14_2);

[0008] As a preferred, the medium stack (0_0) adopts a multi-layer structure, and sequentially includes, from bottom to top, a high-resistance silicon substrate (1_0), a first oxide medium layer (2_0), a second oxide medium layer (3_0), an ethyl silicate medium layer (4_0), a third oxide medium layer (5_0), a first silicon nitride medium layer (6_0), a fourth oxide medium layer (7_0), a second silicon nitride medium layer (8_0), a fifth oxide medium layer (9_0), a third silicon nitride medium layer (10_0), a sixth oxide medium layer (11_0), a fourth silicon nitride medium layer (12_0), a seventh oxide medium layer (13_0), an eighth oxide medium layer (14_0), and a fifth silicon nitride medium layer (15_0);

[0009] As a preferred, the metal layer of the signal input port (1_2) and the signal output port (2_2) penetrates the fourth silicon nitride medium layer (12_0), the seventh oxide medium layer (13_0), and the eighth oxide medium layer (14_0); the signal input first ground (3_2), the second ground (4_2), the third ground (5_2), and the fourth ground (6_2) penetrate the fourth silicon nitride medium layer (12_0), the seventh oxide medium layer (13_0), and the eighth oxide medium layer (14_0);

[0010] As preferred, the first inductor (13_2), the second inductor (14_2), the third inductor (15_2), and the fourth inductor (16_2) are in the form of regular octagonal inductors, and are arranged inside the first silicon nitride dielectric layer (6_0), the fourth oxide dielectric layer (7_0), the second silicon nitride dielectric layer (8_0), the fifth oxide dielectric layer (9_0), the third silicon nitride dielectric layer (10_0), and the sixth oxide dielectric layer (11_0); the first inductor (13_2), the second inductor (14_2), the third inductor (15_2), and the fourth inductor (16_2) are connected with other devices through the metal via V1 in the third oxide dielectric layer (5_0);

[0011] As preferred, the first capacitor (7_2), the second capacitor (8_2), the third capacitor (9_2), the fourth capacitor (10_2), the fifth capacitor (11_2), and the sixth capacitor (12_2) are in the metal-dielectric-metal structure, and are built in the third oxide dielectric layer (5_0); the upper metal plate of the capacitor is made of titanium nitride, the lower metal plate of the capacitor is made of aluminum, and the dielectric material filled in the capacitor is silicon nitride with a thickness of 0.1 microns; the capacitor is connected with other devices through the metal via V1 in the third oxide dielectric layer (5_0);

[0012] More preferably, the dielectric constant and the loss tangent of the silicon nitride filled in the capacitor in the third oxide dielectric layer (5_0) are 7 and 0.004 respectively, and the thickness is 0.1 microns;

[0013] As preferred, the first ground (3), the second ground (4), the signal port (1), the output port first ground (5), the output port second ground (6), and the signal port (2) are in the form of GSG probe feeding.

[0014] The present application has the following advantages:

[0015] 1. The high-resistance silicon (H-SI) material is used as the dielectric substrate, so that the insertion loss of the device can be reduced.

[0016] 2. On the basis of the mixed topology structure of the traditional third-order high-pass filter and the third-order band-pass filter, some components insensitive to performance are reduced by introducing cross-capacitive coupling, so as to achieve the purposes of wide out-of-band suppression capability, high roll-off coefficient and miniaturization; the upper sideband transmission zero point is mainly composed of parallel inductance-capacitance resonant units, the lower sideband transmission zero point is mainly composed of cross-coupling capacitors, and the remaining two transmission zero points of the upper sideband are mainly caused by inductive or capacitive coupling of compact structure, so as to realize the wide out-of-band suppression performance. The topology structure of the high-pass filter combined with the band-pass filter is adopted, and some insensitive components are reduced on this basis to reduce the overall size of the device; in order to improve the out-of-band suppression capability, parallel inductance-capacitance units and cross-coupling capacitors are introduced to improve the out-of-band suppression performance and the roll-off coefficient.

[0017] 3. The miniaturized integrated passive device manufacturing process is easy to integrate with other radio frequency chip modules, so as to be integrated into the entire radio frequency front-end system.

[0018] 4. The band-pass filter of the present application works in the 5G frequency band of 3300-42MHz, has high roll-off coefficient, wide out-of-band suppression capability and low insertion loss.

[0019] 5. It is suitable for wireless communication systems such as mobile phones, wireless Bluetooth, Wifi and wearable devices. DETAILED DESCRIPTION

[0020] Figure 1 The stack information of the high-resistance silicon process; wherein the dielectric stack 0_0, the high-resistance silicon substrate 1_0, the first oxide dielectric layer 2_0, the second oxide dielectric layer 3_0, the ethyl silicate dielectric layer 4_0, the third oxide dielectric layer 5_0, the first silicon nitride dielectric layer 6_0, the fourth oxide dielectric layer 7_0, the second silicon nitride dielectric layer 8_0, the fifth oxide dielectric layer 9_0, the third silicon nitride dielectric layer 10_0, the sixth oxide dielectric layer 11_0, the fourth silicon nitride dielectric layer 12_0, the seventh oxide dielectric layer 13_0, the eighth oxide dielectric layer 14_0, and the fifth silicon nitride dielectric layer 15_0 are provided.

[0021] Figure 2 The schematic diagram topology structure of the proposed IPD filter; wherein the first capacitor 1_1, the second capacitor 2_1, the third capacitor 3_1, the fourth capacitor 4_1, the fifth capacitor 5_1, the sixth capacitor 6_1, the first inductor 7_1, the second inductor 8_1, the third inductor 9_1, and the fourth inductor 10_1 are provided.

[0022] Figure 3 The schematic diagram simulation result of the proposed IPD filter is provided.

[0023] Figure 4The circuit structure of the proposed IPD filter; wherein ground 0_2, first signal input end 1_2, second signal output end 2_2, first ground 3_2, second ground 4_2, third ground 5_2, fourth ground 6_2, first capacitor 7_2, second capacitor 8_2, third capacitor 9_2, fourth capacitor 10_2, fifth capacitor 11_2, sixth capacitor 12_2, first inductor 13_2, second inductor 14_2, third inductor 15_2, fourth inductor 16_2;

[0024] Figure 5 The electromagnetic simulation results of the proposed IPD filter. DETAILED DESCRIPTION

[0025] In order to more clearly illustrate the problems solved by the present application, the technical solutions adopted and the beneficial effects, the specific embodiments of the present application will be described below in conjunction with the drawings, the preferred embodiments described herein are only used to illustrate and explain the present application, and do not limit the present application, any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be within the protection scope of the present application.

[0026] An IPD filter with high roll-off coefficient and wide out-of-band suppression performance of high-resistance silicon process, the filter comprising a dielectric stack 0 and a filter circuit structure formed on the dielectric stack 0.

[0027] As shown in Figure 1 The dielectric stack 0_0 adopts a multi-layer structure, from bottom to top, including high-resistance silicon substrate 1_0, first oxide dielectric layer 2_0, second oxide dielectric layer 3_0, ethyl silicate dielectric layer 4_0, third oxide dielectric layer 5_0, first silicon nitride dielectric layer 6_0, fourth oxide dielectric layer 7_0, second silicon nitride dielectric layer 8_0, fifth oxide dielectric layer 9_0, third silicon nitride dielectric layer 10_0, sixth oxide dielectric layer 11_0, fourth silicon nitride dielectric layer 12_0, seventh oxide dielectric layer 13_0, eighth oxide dielectric layer 14_0, fifth silicon nitride dielectric layer 15_0.

[0028] The high-resistance silicon substrate 1_0 adopts high-resistance silicon material, the dielectric constant and loss tangent are 11.9 and 0.004 respectively, and the thickness is 725 microns;

[0029] The dielectric constant and loss tangent of the oxide adopted by the first oxide dielectric layer 2_0 are 4 and 0.01 respectively, and the thickness is 0.0084 microns;

[0030] The dielectric constant and loss tangent of the oxide adopted by the second signal output end second oxide dielectric layer 3_0 are 4 and 0.01 respectively, and the thickness is 4 microns;

[0031] The dielectric constant and loss tangent of ethyl silicate used by the ethyl silicate medium layer 4_0 of the second signal output end are 4.2 and 0.01 respectively, and the thickness is 0.35 microns;

[0032] The dielectric constant and loss tangent of oxide used by the third oxide medium layer 5_0 of the second signal output end are 4 and 0.01 respectively, and the thickness is 3.05 microns;

[0033] The dielectric constant and loss tangent of silicon nitride used by the first silicon nitride medium layer 6_0 of the second signal output end are 7 and 0.004 respectively, and the thickness is 0.1 microns;

[0034] The dielectric constant and loss tangent of oxide used by the fourth oxide medium layer 7_0 of the second signal output end are 4 and 0.01 respectively, and the thickness is 2.9 microns;

[0035] The dielectric constant and loss tangent of silicon nitride used by the second silicon nitride medium layer 8_0 of the second signal output end are 7 and 0.004 respectively, and the thickness is 0.1 microns;

[0036] The dielectric constant and loss tangent of oxide used by the fifth oxide medium layer 9_0 of the second signal output end are 4 and 0.01 respectively, and the thickness is 2.9 microns;

[0037] The dielectric constant and loss tangent of silicon nitride used by the third silicon nitride medium layer 10_0 of the second signal output end are 7 and 0.004 respectively, and the thickness is 0.1 microns;

[0038] The dielectric constant and loss tangent of oxide used by the sixth oxide medium layer 11_0 of the second signal output end are 4 and 0.01 respectively, and the thickness is 2.9 microns;

[0039] The dielectric constant and loss tangent of silicon nitride used by the fourth silicon nitride medium layer 12_0 of the second signal output end are 7 and 0.004 respectively, and the thickness is 0.07 microns;

[0040] The dielectric constant and loss tangent of oxide used by the seventh oxide medium layer 13_0 of the second signal output end are 4 and 0.01 respectively, and the thickness is 0.4 microns;

[0041] The dielectric constant and loss tangent of oxide used by the eighth oxide medium layer 14_0 of the second signal output end are 4 and 0.01 respectively, and the thickness is 0.4 microns;

[0042] The dielectric constant and loss tangent of silicon nitride used by the fifth silicon nitride medium layer 15_0 of the second signal output end are 7 and 0.004 respectively, and the thickness is 0.4 microns;

[0043] As Figure 4The filter circuit structure is externally provided with a ground 0_2; the input port is composed of ground-signal-ground, including a first ground 3_2, a first signal input end 1_2 and a second ground 4_2; the output port is composed of ground-signal-ground, mainly including a third ground 5_2, a second signal output end 2_2 and a fourth ground 6_2; the first signal end 1_2 is connected to the first input port of a first capacitor 7_2 through a transmission line, the first output port of the first capacitor 7_2 is connected to the input end of a second capacitor 8_2 through a transmission line, and the second output port of the first capacitor 7_2 is connected to the input end of a first inductor 13_2 through a transmission line, the output end of the first inductor 13_2 is connected to the input end of a third capacitor 9_2 through a transmission line, and the output end of the third capacitor 9_2 is connected to the ground 0_2; the output end of the second capacitor 8_2 is connected to the input end of a second inductor 14_2 through a transmission line, the first output end of the second inductor 14_2 is connected to the input end of a fourth inductor 16_2 through a transmission line, the output end of the fourth inductor 16_2 is connected to the input end of a fifth capacitor 11_2 through a transmission line, and the output port of the fifth capacitor 11_2 is connected to the output signal port 2_2 through a transmission line; the second output end of the second inductor 14_2 is connected to the input end of a third inductor 15_2 through a transmission line, and the output end of the third inductor 15_2 is connected to the ground 0_2; the third output end of the second inductor 14_2 is connected to the input end of a fourth capacitor 10_2 through a transmission line, and the output port of the fourth capacitor 10_2 is connected to the ground 0_2; the third output port of the first capacitor 7_2 is connected to the input port of a sixth capacitor 12_2 through a transmission line, and the output port of the sixth capacitor 12_2 is connected to the output port of the second inductor 14_2 through a transmission line;

[0044] The first capacitor 7_2, the sixth capacitor 12_2, the third capacitor 9_2 and the first inductor 13_2 constitute a three-order high-pass filter; the second capacitor 8_2, the fourth capacitor 10_2, the fifth capacitor 11_2, the second inductor 14_2, the third inductor 15_2 and the fourth inductor 16_2 constitute a three-order band-pass filter, wherein the second capacitor 8_2 is shared by the high-pass filter and the band-pass filter; the upper sideband out-of-band transmission zero point tuning element and the lower sideband out-of-band transmission zero point tuning element constitute the out-of-band transmission zero point tuning element, the upper sideband out-of-band transmission zero point tuning element is controlled by a parallel resonance unit, the parallel resonance unit includes the first inductor 13_2 and the third capacitor 9_2, and the lower sideband out-of-band transmission zero point tuning element is controlled by a cross element sixth capacitor 12_2, and is simultaneously affected by the second capacitor 8_2 and the second inductor 14_2.

[0045] As Figure 2As shown, the filter circuit topology is composed of one third-order high-pass filter, one third-order band-pass filter and two out-of-band transmission zero tuning elements; wherein the third-order high-pass filter includes first capacitor 1_1, second capacitor 2_1, third capacitor 3_1 and first inductor 7_1; the third-order band-pass filter includes second capacitor 2_1, fourth capacitor 4_1, fifth capacitor 5_1, second inductor 8_1 and third inductor 9_1, fourth inductor 10_1, wherein the second capacitor 2_1 is shared by the high-pass filter and the band-pass filter; the out-of-band transmission zero tuning elements include upper sideband out-of-band transmission zero tuning element and lower sideband out-of-band transmission zero tuning element, the upper sideband out-of-band zero tuning element is mainly controlled by a parallel resonance unit, and the parallel resonance unit includes first inductor 7_1 and second capacitor 3_1, and the lower sideband out-of-band zero sensing is mainly controlled by a cross element sixth capacitor 6_1, and can also be affected by second capacitor 2_1 and second inductor 8_1. 1 is the input end, and 2 is the output end.

[0046] The metal layer of the signal input port 1_2 and the signal output port 2_2 penetrates the fourth silicon nitride dielectric layer 12_0, the seventh oxide dielectric layer 13_0 and the eighth oxide dielectric layer 14_0; the signal input first ground 3_2, the second ground 4_2, the third ground 5_2 and the fourth ground 6_2 penetrate the fourth silicon nitride dielectric layer 12_0, the seventh oxide dielectric layer 13_0 and the eighth oxide dielectric layer 14_0.

[0047] The first inductor 13_2, the second inductor 14_2, the third inductor 15_2 and the fourth inductor 16_2 all adopt the form of regular octagonal inductor. The first inductor 13_2, the second inductor 14_2, the third inductor 15_2 and the fourth inductor 16_2 are all arranged inside the first silicon nitride dielectric layer 6_0, the fourth oxide dielectric layer 7_0, the second silicon nitride dielectric layer 8_0, the fifth oxide dielectric layer 9_0, the third silicon nitride dielectric layer 10_0 and the sixth oxide dielectric layer 11_0; the first inductor 13_2, the second inductor 14_2, the third inductor 15_2 and the fourth inductor 16_2 are connected with other devices through the metal via hole V1 in the third oxide dielectric layer 5_0.

[0048] The first capacitor 7_2, the second capacitor 8_2, the third capacitor 9_2, the fourth capacitor 10_2, the fifth capacitor 11_2 and the sixth capacitor 12_2 are built-in in the third oxide dielectric layer 5_0, and are connected with other devices through the metal via hole V1 in the third oxide dielectric layer 5_0.

[0049] The first capacitor 7_2, the second capacitor 8_2, the third capacitor 9_2, the fourth capacitor 10_2, the fifth capacitor 11_2 and the sixth capacitor 12_2 adopt a metal-dielectric-metal structure.

[0050] The first ground 3, the second ground 4, the signal port 1, the first ground 5, the second ground 6 and the signal port 2 adopt a probe feeding form of GSG.

[0051] The IPD filter of the application is based on the mixed topology structure of the traditional third-order high-pass filter and the third-order band-pass filter, and zero-point control technology is added to realize high roll-off coefficient and wide out-of-band suppression capability.

[0052] The third-order high-pass filter comprises a first capacitor 1_1, a second capacitor 2_1, a third capacitor 3_1 and a first inductor 7_1; the third-order band-pass filter comprises a second capacitor 2_1, a fourth capacitor 4_1, a fifth capacitor 5_1, a second inductor 8_1, a third inductor 9_1 and a fourth inductor 10_1, wherein the second capacitor 2_1 is shared by the high-pass filter and the band-pass filter; the out-of-band transmission zero-point tuning element comprises an upper sideband out-of-band transmission zero-point tuning element and a lower sideband out-of-band transmission zero-point tuning element, the upper sideband out-of-band zero-point tuning element mainly comprises a parallel resonance unit comprising a first inductor 7_1 and a second capacitor 3_1, and the lower sideband out-of-band zero-point sensing is mainly controlled by a cross element sixth capacitor 6_1, and can also be affected by the second capacitor 2_1 and the second inductor 8_1.

[0053] The values of all inductors and capacitors in the patent are optimized in electromagnetic simulation software, and the specific values are as follows.

[0054] The metal plate length of the first capacitor 7_1 is 27um, and the width is 55um;

[0055] The metal plate length of the second capacitor 8_1 is 12um, and the width is 25um;

[0056] The metal plate length of the third capacitor 9_1 is 27um, and the width is 50um;

[0057] The metal plate length of the fourth capacitor 10_1 is 50um, and the width is 42um;

[0058] The metal plate length of the fifth capacitor 11_1 is 30um, and the width is 21um;

[0059] The metal plate length of the sixth capacitor 12_1 is 18um, and the width is 30um.

[0060] The inner diameter of the first inductor 13_1 is 62um, and the number of turns is 5.5 turns;

[0061] The inner diameter of the second inductor 14_1 is 65um, and the number of turns is 5.5 turns;

[0062] The inner diameter of the third inductor 15_1 is 40um, and the number of turns is 2.5 turns;

[0063] The inner diameter of the fourth inductor 16_1 is 55um, and the number of turns is 4.5 turns;

[0064] The input port is composed of ground-signal-ground, including the first ground 3_2, the first signal input end 1_2 and the second ground 4_2; the output port is composed of ground-signal-ground, mainly including the third ground 5_2, the second signal output end 2_2 and the fourth ground 6_2; and the pad size is 80um*80um.

[0065] The working bandwidth of the filter completely covers the 5G communication frequency band 3300-4200MHz; the return loss S 11 is basically below-18dB; the insertion loss S 21 is less than 1.7dB; in the upper band frequency band (0-2.5GHz), the out-of-band suppression is less than-20dB, in the lower band frequency band (5.15-15GHz), the out-of-band suppression is less than-20dB, achieving the wide out-of-band suppression target, and the roll-off coefficient reaches the level of 1.5. The IPD bandpass filter of the present application is a compact structure, light weight, small size, easy to integrate with the radio frequency transceiver front end into a chip, meeting the needs of 5G wireless communication for passive integrated devices.

[0066] The above examples are not a limitation of the present application, and the present application is not limited to the above examples, as long as it meets the requirements of the present application, it belongs to the protection scope of the present application.

Claims

1. A bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon technology, characterized in that The filter comprises a dielectric stack (0) and a filter circuit structure formed on the dielectric stack (0); The filter circuit structure is provided with a ground (0_2) at the periphery; the input port is composed of ground-signal-ground, including a first ground (3_2), a first signal input end (1_2) and a second ground (4_2); the output port is composed of ground-signal-ground, including a third ground (5_2), a second signal output end (2_2) and a fourth ground (6_2); the first signal end (1_2) is connected to the first input port of the first capacitor (7_2) through a transmission line, the first output port of the first capacitor (7_2) is connected to the input end of the second capacitor (8_2) through a transmission line, and the second output port of the first capacitor (7_2) is connected to the input end of the first inductor (13_2) through a transmission line, the output end of the first inductor (13_2) is connected to the input end of the third capacitor (9_2) through a transmission line, and the output end of the third capacitor (9_2) is connected to the ground (0_2); the output end of the second capacitor (8_2) is connected to the input end of the second inductor (14_2) through a transmission line, the first output end of the second inductor (14_2) is connected to the input end of the fourth inductor (16_2) through a transmission line, the output end of the fourth inductor (16_2) is connected to the input end of the fifth capacitor (11_2) through a transmission line, and the output port of the fifth capacitor (11_2) is connected to the output signal port (2_2) through a transmission line; the second output end of the second inductor (14_2) is connected to the input end of the third inductor (15_2) through a transmission line, and the output end of the third inductor (15_2) is connected to the ground (0_2); the third output end of the second inductor (14_2) is connected to the input end of the fourth capacitor (10_2) through a transmission line, and the output port of the fourth capacitor (10_2) is connected to the ground (0_2); the third output port of the first capacitor (7_2) is connected to the input port of the sixth capacitor (12_2) through a transmission line, and the output port of the sixth capacitor (12_2) is connected to the output port of the second inductor (14_2) through a transmission line; The first capacitor (7_2), the sixth capacitor (12_2), the third capacitor (9_2) and the first inductor (13_2) constitute a three-order high-pass filter; the second capacitor (8_2), the fourth capacitor (10_2), the fifth capacitor (11_2), the second inductor (14_2), the third inductor (15_2) and the fourth inductor (16_2) constitute a three-order band-pass filter, wherein the second capacitor (8_2) is shared by the high-pass filter and the band-pass filter; the upper band out-of-band transmission zero tuning element and the lower band out-of-band transmission zero tuning element constitute the out-of-band transmission zero tuning element, the upper band out-of-band transmission zero tuning element is controlled by a parallel resonance unit, the parallel resonance unit includes the first inductor (13_2) and the third capacitor (9_2), and the lower band out-of-band transmission zero tuning element is controlled by a cross element sixth capacitor (12_2) and is affected by the second capacitor (8_2) and the second inductor (14_2).

2. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon process according to claim 1, characterized in that The medium stack (0_0) adopts a multi-layer structure, and from bottom to top, it includes a high-resistance silicon substrate (1_0), a first oxide medium layer (2_0), a second oxide medium layer (3_0), an ethyl silicate medium layer (4_0), a third oxide medium layer (5_0), a first silicon nitride medium layer (6_0), a fourth oxide medium layer (7_0), a second silicon nitride medium layer (8_0), a fifth oxide medium layer (9_0), a third silicon nitride medium layer (10_0), a sixth oxide medium layer (11_0), a fourth silicon nitride medium layer (12_0), a seventh oxide medium layer (13_0), an eighth oxide medium layer (14_0), and a fifth silicon nitride medium layer (15_0).

3. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon process according to claim 2, characterized in that The metal layer of the signal input port (1_2) and the signal output port (2_2) penetrates the fourth silicon nitride medium layer (12_0), the seventh oxide medium layer (13_0), and the eighth oxide medium layer (14_0); the signal input first ground (3_2), the second ground (4_2), the third ground (5_2), and the fourth ground (6_2) penetrate the fourth silicon nitride medium layer (12_0), the seventh oxide medium layer (13_0), and the eighth oxide medium layer (14_0).

4. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon technology according to claim 1, characterized in that The first inductor (13_2), the second inductor (14_2), the third inductor (15_2), and the fourth inductor (16_2) all adopt the form of regular octagonal inductor.

5. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistivity silicon process according to claim 2 or 3, characterized in that The first inductor (13_2), the second inductor (14_2), the third inductor (15_2), and the fourth inductor (16_2) are all arranged inside the first silicon nitride medium layer (6_0), the fourth oxide medium layer (7_0), the second silicon nitride medium layer (8_0), the fifth oxide medium layer (9_0), the third silicon nitride medium layer (10_0), and the sixth oxide medium layer (11_0); the first inductor (13_2), the second inductor (14_2), the third inductor (15_2), and the fourth inductor (16_2) are connected with other devices through the metal via V1 in the third oxide medium layer (5_0).

6. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon technology according to claim 1, characterized in that The first capacitor (7_2), the second capacitor (8_2), the third capacitor (9_2), the fourth capacitor (10_2), the fifth capacitor (11_2), and the sixth capacitor (12_2) are built in the third oxide medium layer (5_0) and are connected with other devices through the metal via V1 of the third oxide medium layer (5_0).

7. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon technology according to claim 1, characterized in that The first capacitor (7_2), the second capacitor (8_2), the third capacitor (9_2), the fourth capacitor (10_2), the fifth capacitor (11_2), and the sixth capacitor (12_2) all adopt the metal-dielectric-metal structure.

8. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon process according to claim 7, characterized in that The upper metal plate of the metal-dielectric-metal structure is made of titanium nitride, the lower metal plate is made of aluminum, and the dielectric material filled in the middle is silicon nitride with a thickness of 0.1 microns.

9. The bandpass filter with high roll-off coefficient and wide out-of-band rejection based on high-resistive silicon technology according to claim 1, characterized in that The first ground (3), the second ground (4), the signal port (1), the first ground (5), the second ground (6), and the signal port (2) all adopt the GSG probe feeding form.

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