CN208092125U - Microwave power detector based on clamped beam piezoresistive effect - Google Patents
Microwave power detector based on clamped beam piezoresistive effect Download PDFInfo
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- CN208092125U CN208092125U CN201820657756.7U CN201820657756U CN208092125U CN 208092125 U CN208092125 U CN 208092125U CN 201820657756 U CN201820657756 U CN 201820657756U CN 208092125 U CN208092125 U CN 208092125U
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- clamped beam
- diffusion resistance
- microwave power
- power detector
- cpw
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- 230000000694 effects Effects 0.000 title claims abstract description 18
- 238000009792 diffusion process Methods 0.000 claims abstract description 96
- 239000000758 substrate Substances 0.000 claims abstract description 15
- 230000005540 biological transmission Effects 0.000 claims abstract description 10
- 238000005259 measurement Methods 0.000 claims abstract description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 6
- 229910052802 copper Inorganic materials 0.000 claims description 5
- 239000010949 copper Substances 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 239000004411 aluminium Substances 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 230000005611 electricity Effects 0.000 claims description 3
- 229910052732 germanium Inorganic materials 0.000 claims description 3
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 claims description 3
- 229910021421 monocrystalline silicon Inorganic materials 0.000 claims description 3
- 229910052759 nickel Inorganic materials 0.000 claims description 3
- 238000001514 detection method Methods 0.000 description 6
- 230000006835 compression Effects 0.000 description 4
- 238000007906 compression Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000005684 electric field Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
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Abstract
The utility model is a kind of microwave power detector based on clamped beam piezoresistive effect,Including HR-Si substrate,Coplanar waveguide transmission line is provided on HR-Si substrate,Clamped beam,Coplanar waveguide transmission line includes CPW signal wires and CPW ground wires,Clamped beam bridge pier is also respectively provided between CPW ground wires and CPW signal wires,The both ends of clamped beam are fixed on the top of CPW signal wires by clamped beam bridge pier respectively,The both ends of clamped beam are connected by clamped beam bridge pier with HR-Si substrate,In the surface of CPW signal wires,The upper surface of clamped beam is provided with metallic gauge block,The upper and lower surface of clamped beam is both provided with diffusion resistance,Clamped beam deformation causes clamped beam surface stress to change when microwave power detector works,The value of diffusion resistance generates variation,Microwave power value can be directly measured by voltage change between Huygens's bridge measurement node.The microwave power detector structure novel of the utility model is easily integrated, and measurement range is wider, measurement accuracy is higher.
Description
Technical field
The utility model is related to micro-electromechanical system fields, and in particular to a kind of microwave based on clamped beam piezoresistive effect
Power sensor.
Background technology
In radio-frequency micro electromechanical system（RF MEMS）Research in, for microwave signal power be characterize microwave signal one
A important parameter.It is applied to the links such as generation, transmission and the reception of microwave signal for the detection of microwave power, it is most commonly seen
Microwave signal power sensor is the capacitance microwave power sensor based on fixed beam structure, as the clamped beam types of MEMS are micro- online
Wave power sensor and preparation method thereof（The patent No.：201010223810.5）, it is based on clamped beam and direct-type power sensor
Microwave detection system and its detection method（The patent No.：201310027303.8）.The work of this kind of microwave power detector is former
Reason is：When microwave signal passes through co-planar waveguide, electrostatic force is generated between co-planar waveguide and clamped beam, clamped beam is made to pull down, survey
The capacitance variation between electrode and clamped beam is tried, realizes the detection to microwave power.However, capacitance microwave power sensor
Output have non-linear, parasitic capacitance and distribution capacity are affected to sensitivity and measurement accuracy, and connection circuit is more multiple
Miscellaneous, clamped beam pulls down the shortcomings of amplitude is smaller.
Invention content
To solve the above-mentioned problems, the utility model provides a kind of microwave power sensing based on clamped beam piezoresistive effect
Device can effectively solve the problem that the above problem and effectively improves sensitivity, the microwave power detector using piezoresistive effect generate with it is micro-
The one-to-one output voltage of wave power has higher measurement accuracy, higher stability, higher good to measure
The features such as product rate.
In order to achieve the above object, the utility model is achieved through the following technical solutions：
The utility model is a kind of microwave power detector based on clamped beam piezoresistive effect, and sensor includes High Resistivity Si lining
Bottom, is provided with coplanar waveguide transmission line, clamped beam on HR-Si substrate, and coplanar waveguide transmission line includes CPW signal wires and CPW
There are CPW ground wires in the both sides of ground wire, CPW signal wires respectively, and clamped beam is also respectively provided between CPW ground wires and CPW signal wires
Bridge pier, the both ends of clamped beam are fixed on the top of CPW signal wires by clamped beam bridge pier respectively, and the both ends of clamped beam pass through clamped
Beam bridge pier is connected with HR-Si substrate, and the upper surface of the surface of CPW signal wires, clamped beam is provided with metallic gauge block, Gu
The upper and lower surface of strutbeam is both provided with diffusion resistance, when microwave power detector works clamped beam deformation cause clamped beam surface to be answered
Power changes, and the value of diffusion resistance generates variation, can directly be measured by voltage change between Huygens's bridge measurement node
Microwave power value.
Further improvement of the utility model is：Diffusion resistance includes diffusion resistance R1, diffusion resistance R2, diffusion resistance
R3, diffusion resistance R4, diffusion resistance R1 ', diffusion resistance R2 ', diffusion resistance R3 ' and diffusion resistance R4 ', the upper table of clamped beam
Face, metallic gauge block side be diffusion resistance R1 and diffusion resistance R2, the upper surface of clamped beam, the other side of metallic gauge block
It is diffusion resistance R3 and expansion in the side of the lower surface of clamped beam, metallic gauge block for diffusion resistance R1 ' and diffusion resistance R2 '
Resistance R4 is dissipated, is diffusion resistance R3 ' and diffusion resistance R4 ' in the other side of the lower surface of clamped beam, metallic gauge block.
Further improvement of the utility model is：Diffusion resistance R1, diffusion resistance R2, diffusion resistance R3 and diffusion resistance
R4 is by being electrically connected composition Huygens's electric bridge, the diffusion resistance R1 ', diffusion resistance R2 ', diffusion resistance R3 ' and diffusion electricity
Resistance R4 ' is by being electrically connected composition Huygens's electric bridge.
Further improvement of the utility model is：Clamped beam bridge pier is in direct contact with HR-Si substrate, clamped beam bridge pier
It is in direct contact with clamped beam.
Further improvement of the utility model is：Metallic gauge block is copper, metallic gauge block made of nickel or aluminium.
Further improvement of the utility model is：Metallic gauge block is in direct contact with clamped beam.
Further improvement of the utility model is：Clamped beam is clamped made of the monocrystalline silicon or monocrystalline germanium of weak doping
Beam.
Further improvement of the utility model is：Clamped beam bridge pier is clamped beam bridge pier made of copper.
The utility model has the beneficial effects that：（1）The utility model use fixed beam structure, have higher stability,
Higher yields, better environmental suitability, while being easy through microfabrication realization etc. a little；（2）The utility model is adopted
Use clamped beam as mechanical structure, the mechanical characteristic of clamped beam itself is capable of providing the item of four resistance needed for differential bridge
Part；（3）The piezoresistive effect of semi-conducting material is utilized in the utility model, and the resistance on clamped beam is driven by extraneous constant-current source,
Differential bridge is formed between resistance, is detected by electric bridge, sensor accuracy bigger；（4）The utility model is larger using density
Metallic gauge block is positioned on the clamped beam right over signal wire, increases the displacement amplitude of clamped beam, is measured to increase
Precision.
The utility model is to be based on MEMS technology, and the principal advantages with MEMS are small, light-weight, low in energy consumption, are convenient for
It integrates, this series of advantages is that traditional microwave power detector is incomparable, therefore it has and studies and answer well
, due to electrostatic force so that metallic gauge block drives clamped beam drop-down, caused when microwave power is from coplanar wave guide transmission with value
Beam surface stress changes, and to which the resistivity of the diffusion resistance on clamped beam changes, external constant-current source drives diffusion resistance,
Generation and the one-to-one potential difference of microwave power on resistance, pass through and detect the detection that potential difference carries out microwave power.
Microwave power detector structure novel described in the utility model is easily integrated, and measurement range is wider, measures essence
Degree is higher.
Description of the drawings
Fig. 1 is the structural schematic diagram of the utility model.
Fig. 2 is the utility model diffusion resistance arrangement schematic diagram.
Fig. 3 is the utility model Huygens's bridge circuit schematic diagram.
Wherein：1- HR-Si substrates；2-CPW ground wires；3-CPW signal wires；4- clamped beam bridge piers；5- clamped beams；6- is spread
Resistance；7- metallic gauge blocks.
Specific implementation mode
In order to deepen the understanding to the utility model, the utility model is done further below in conjunction with drawings and examples
Detailed description, the embodiment are only used for explaining the utility model, do not constitute and limit to the scope of protection of the utility model.
As shown in Figs. 1-3, the utility model is a kind of microwave power detector based on clamped beam piezoresistive effect, the biography
Sensor includes HR-Si substrate 1, and coplanar waveguide transmission line, clamped beam 5 are provided on the HR-Si substrate 1, described clamped
Beam 5 is clamped beam made of the monocrystalline silicon or monocrystalline germanium of weak doping, and the coplanar waveguide transmission line includes CPW signal wires 3 and CPW
There are CPW ground wires 2 in the both sides of ground wire 2, the CPW signal wires 3 respectively, between the CPW ground wires 2 and the CPW signal wires 3 also
It is respectively arranged with clamped beam bridge pier 4, the clamped beam bridge pier 4 is clamped beam bridge pier made of copper, the both ends point of the clamped beam 5
The top of the CPW signal wires 3 is not fixed on by clamped beam bridge pier 4, the both ends of the clamped beam 5 pass through clamped beam bridge pier 4
It is connected with the HR-Si substrate 1, the clamped beam bridge pier 4 is in direct contact with the HR-Si substrate 1, the clamped beam bridge pier
4 are in direct contact with the clamped beam 5, and the upper surface of the surface of the CPW signal wires 3, the clamped beam 5 is provided with metal
Mass block 7, clamped beam top are provided with made of metal mass block, and signal wire generates electrostatic force pulling quality to sensor at work
Block, to drive clamped beam to generate deformation, clamped beam surface generates stress variation, while mass block can increase the width of deformation
Degree, center signal line have microwave signal by when, a certain amount of electrostatic force will be generated, metallic gauge block is by electrostatic force band
Dynamic clamped beam drop-down, causes the stress on clamped beam surface to change, and the metallic gauge block 7 is gold made of copper, nickel or aluminium
Belong to mass block, the metallic gauge block 7 is in direct contact with the clamped beam 5, and the upper and lower surface of the clamped beam 5 is both provided with expansion
Dissipate resistance 6, when microwave power detector work 5 deformation of clamped beam cause 5 surface stress of clamped beam to change, diffusion resistance
Value generates variation, and microwave power value can be directly measured by voltage change between Huygens's bridge measurement node 2,4, described
Diffusion resistance 6 includes diffusion resistance R1, diffusion resistance R2, diffusion resistance R3, diffusion resistance R4, diffusion resistance R1 ', diffusion resistance
R2 ', diffusion resistance R3 ' and diffusion resistance R4 ', the upper surface of the clamped beam 5, the metallic gauge block 7 side be diffusion
Resistance R1 and diffusion resistance R2, the upper surface of the clamped beam 5, the metallic gauge block 7 the other side be diffusion resistance R1 ' and
Diffusion resistance R2 ' is diffusion resistance R3 and diffusion resistance in the side of the lower surface of the clamped beam 5, the metallic gauge block 7
R4 is diffusion resistance R3 ' and diffusion resistance R4 ' in the other side of the lower surface of the clamped beam 5, the metallic gauge block 7, expands
Resistance R1, diffusion resistance R2, diffusion resistance R3 and diffusion resistance R4 are dissipated by being electrically connected composition Huygens's electric bridge, the diffusion
Resistance R1 ', diffusion resistance R2 ', diffusion resistance R3 ' and diffusion resistance R4 ' are by being electrically connected composition Huygens's electric bridge, also
It is to say that clamped beam both sides upper and lower surface is both provided with diffusion resistance close to the part of bridge pier and mass block, diffusion resistance totally 8, Gu
Strutbeam is per the diffusion resistance of side 4 by being electrically connected composition differential bridge.
By taking a side resistance as an example, diffusion resistance R1, diffusion resistance R2, diffusion resistance R3 and diffusion resistance R4 constitute Huygens
Bridge, node 1 and node 3 are driven by extraneous constant-current source I1, and node 2 and node 4 are output signal U out, with external AD converter phase
Even, it is detected for external AD converter.
When signal wire passes through microwave signal, certain electrostatic force will be generated to mass block, mass block drives clamped beam hair
Raw deformation, the stress on clamped beam surface change, by taking unilateral four diffusion resistances of clamped beam as an example, diffusion resistance R1, diffusion
The stress that resistance R2, diffusion resistance R3 and diffusion resistance R4 are subject to is as shown in table 1：
The unilateral clamped beam diffusion resistance stress variation of 1 clamped beam of table drop-down
| R1 | R2 | R3 | R4 | |
| Pull-up | Compression | It stretches | It stretches | Compression |
| Drop-down | It stretches | Compression | Compression | It stretches |
The resistance variable that four resistance are generated when clamped beam changes is identical, therefore passes through Huygens's electric bridge shown in Fig. 3
Resistance variations are measured, which is driven using external constant-current source, while utilizing the electricity between external AD conversion module measuring node
Pressure can measure microwave power, and node voltage microwave power is one-to-one, therefore can derive microwave power.
When working sensor, center signal line generates certain electric field force, and metallic gauge block is by band after electric field force effect
Dynamic clamped beam generates deformation, and clamped beam surface generates stress variation, voltage will be generated between two nodes of differential bridge circuit, should
Voltage is corresponded with microwave power, by detecting voltage, to realize the detection of power.
Claims (8)
1. a kind of microwave power detector based on clamped beam piezoresistive effect, the sensor include HR-Si substrate（1）, institute
State HR-Si substrate（1）On be provided with coplanar waveguide transmission line, clamped beam（5）, it is characterised in that：The coplanar waveguide transmission line
Including CPW signal wires（3）With CPW ground wires（2）, the CPW signal wires（3）Both sides have CPW ground wires respectively（2）, in the CPW
Ground wire（2）With the CPW signal wires（3）Between be also respectively provided with clamped beam bridge pier（4）, the clamped beam（5）Both ends point
Do not pass through clamped beam bridge pier（4）It is fixed on the CPW signal wires（3）Top, the clamped beam（5）Both ends pass through clamped beam
Bridge pier（4）With the HR-Si substrate（1）It is connected, in the CPW signal wires（3）Surface, the clamped beam（5）Upper table
Face is provided with metallic gauge block（7）, the clamped beam（5）Upper and lower surface be both provided with diffusion resistance（6）, the microwave power
Clamped beam when working sensor（5）Deformation leads to clamped beam（5）Surface stress changes, diffusion resistance（6）Value generate variation, lead to
Voltage change can directly measure microwave power value between crossing Huygens's bridge measurement node.
2. the microwave power detector according to claim 1 based on clamped beam piezoresistive effect, it is characterised in that：The diffusion
Resistance（6）Including diffusion resistance R1, diffusion resistance R2, diffusion resistance R3, diffusion resistance R4, diffusion resistance R1 ', diffusion resistance
R2 ', diffusion resistance R3 ' and diffusion resistance R4 ', the clamped beam（5）Upper surface, the metallic gauge block（7）Side be
Diffusion resistance R1 and diffusion resistance R2, the clamped beam（5）Upper surface, the metallic gauge block（7）The other side be diffusion
Resistance R1 ' and diffusion resistance R2 ', in the clamped beam（5）Lower surface, the metallic gauge block（7）Side be diffusion electricity
R3 and diffusion resistance R4 is hindered, in the clamped beam（5）Lower surface, the metallic gauge block（7）The other side be diffusion resistance
R3 ' and diffusion resistance R4 '.
3. the microwave power detector according to claim 2 based on clamped beam piezoresistive effect, it is characterised in that：Diffusion resistance
R1, diffusion resistance R2, diffusion resistance R3 and diffusion resistance R4 are by being electrically connected composition Huygens's electric bridge, the diffusion resistance
R1 ', diffusion resistance R2 ', diffusion resistance R3 ' and diffusion resistance R4 ' are by being electrically connected composition Huygens's electric bridge.
4. the microwave power detector according to claim 1 based on clamped beam piezoresistive effect, it is characterised in that：It is described clamped
Beam bridge pier（4）With the HR-Si substrate（1）It is in direct contact, the clamped beam bridge pier（4）With the clamped beam（5）Directly connect
It touches.
5. the microwave power detector according to claim 1 based on clamped beam piezoresistive effect, it is characterised in that：The metal
Mass block（7）For metallic gauge block made of copper, nickel or aluminium.
6. the microwave power detector according to claim 1 based on clamped beam piezoresistive effect, it is characterised in that：The metal
Mass block（7）With the clamped beam（5）It is in direct contact.
7. the microwave power detector according to claim 1 based on clamped beam piezoresistive effect, it is characterised in that：It is described clamped
Beam（5）Clamped beam made of monocrystalline silicon or monocrystalline germanium for weak doping.
8. the microwave power detector according to claim 1 based on clamped beam piezoresistive effect, it is characterised in that：It is described clamped
Beam bridge pier（4）For clamped beam bridge pier made of copper.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201820657756.7U CN208092125U (en) | 2018-05-04 | 2018-05-04 | Microwave power detector based on clamped beam piezoresistive effect |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108594007A (en) * | 2018-05-04 | 2018-09-28 | 南京邮电大学 | Microwave power detector based on clamped beam piezoresistive effect |
| CN109917182A (en) * | 2019-03-27 | 2019-06-21 | 南京邮电大学 | Microwave power detector based on graphene piezoresistance effect |
-
2018
- 2018-05-04 CN CN201820657756.7U patent/CN208092125U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108594007A (en) * | 2018-05-04 | 2018-09-28 | 南京邮电大学 | Microwave power detector based on clamped beam piezoresistive effect |
| CN108594007B (en) * | 2018-05-04 | 2023-05-23 | 南京邮电大学 | Microwave power sensor based on piezoresistive effect of clamped beam |
| CN109917182A (en) * | 2019-03-27 | 2019-06-21 | 南京邮电大学 | Microwave power detector based on graphene piezoresistance effect |
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| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20191202 Address after: Room 107, floor 1, No. 30-06, GuangYue Road, Qixia street, Nanjing Economic and Technological Development Zone, Nanjing, Jiangsu Province Patentee after: Nanjing Erxin Electronic Co.,Ltd. Address before: 210023 No. 9, Wen Yuan Road, Qixia District, Nanjing, Nanjing, Jiangsu. Patentee before: NANJING University OF POSTS AND TELECOMMUNICATIONS |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20181113 |