CN2725900Y

CN2725900Y - Direct heating terminal type microwave power sensor of microelectronic mechanical system

Info

Publication number: CN2725900Y
Application number: CN 200420079786
Authority: CN
Inventors: 廖小平; 陈宁娟
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2004-09-27
Filing date: 2004-09-27
Publication date: 2005-09-14
Anticipated expiration: 2014-09-27

Abstract

The utility model relates to a direct heating terminal type microwave power sensor of a microelectronic mechanical system, which has a structure which realizes the power absorption and heat quantity conversion through making use of terminal load for measuring the input power in a measuring temperature mode. The structure utilizes a thermocouple as the terminal load; the microwave power can be measured through a mode that energy inputted from the coplanar waveguide is converted to the heat quantity and then is converted to voltage. The sensor comprises a substrate, a coplanar waveguide ground wire, a coplanar waveguide signal line, metal thermocouple arms, a AlGaAs thermocouple arm, a welding disk, an ohmic contact device and medium. The manufacture procedures are that a GaAs substrate is prepared; the AlGaAsis deposited; ions are filled for mixing; the photolithography of the AlGaAs is carried out, and the thermocouple arm is formed by the etching; AUGE eutectic is deposited; Ni and Au form the ohmic contact through photolithography and high temperature annealing; a SiON medium layer is deposited; metal is deposited and forms the coplanar waveguide and parts of thermocouple arms through the photolithography; the medium layer is deposited; the welding disk is made.

Description

Directly heat terminal type micro electronic mechanical system microwave power sensor

Technical field

The utility model is that a kind of form of utilizing terminator realizes power absorption and is converted into heat, records the structure of power input in the mode of measuring thermoelectrical potential, belongs to the technical field that microelectromechanical systems (MEMS) is made.

Background technology

In research of microwave technology, microwave power is an important parameter that characterizes the microwave signal feature.In the research of each links such as generation, transmission and reception of microwave signal, microwave power measurement is absolutely necessary, and it has become the important component part of electromagnetic measurement.Big quantity research is all arranged both at home and abroad in this field, but with the microstructure microwave power detector of MEMS (micro-electronic mechanical system technique) development also seldom, the existing in this respect years of researches of China.

Traditional power meter adopts the thermoelectric (al) power sensor of waveguide form: bismuth-antimony commonly used is made thermocouple, adopt concentric cable as transmission line, its major defect is a low-response, the level of burning is low, will use attenuator when measuring high power, can't be integrated with digital-to-analog circuit.

Summary of the invention

Technical matters: the purpose of this utility model provides a kind of direct heating terminal type micro electronic machinery microwave power detector that utilizes thermoelectric conversion to measure microwave power.Use the shortcoming that this sensor can overcome the thermoelectric (al) power sensor of conventional waveguide form, simple in structure, function admirable can realize simply integrated with digital-to-analog circuit.

Technical scheme: the direct heating terminal type MEMS microwave power detector in the utility model is different from the thermoelectric (al) power sensor of traditional waveguide form, this structure utilizes the co-planar waveguide of 50 Ω to come power input, in the parallel connection of co-planar waveguide terminal the thermopair arm of two 100 Ω, the heat that thermopair generates heat absorbed power is converted into DC voltage, according to VD, we can correspondingly learn the size of power input.Structurally this sensor comprises substrate, co-planar waveguide ground wire, co-planar waveguide signal wire, Pt/Au thermocouple arm, AlGaAs thermopair arm, pad, Ohmic contact, medium; Wherein, AlGaAs thermopair arm, medium are located immediately on the substrate, and co-planar waveguide ground wire, co-planar waveguide signal wire are positioned in the middle of the medium, and co-planar waveguide ground wire, co-planar waveguide signal wire are connected by pad draws; The left end of co-planar waveguide signal wire connects pad, and right-hand member connects two branch roads, and wherein a branch road connects the Pt/Au thermocouple arm, the following termination Ohmic contact of the other end of Pt/Au thermocouple arm, and the following termination AlGaAs thermopair arm of Ohmic contact, AlGaAs thermopair arm and pad join; The lower end of the right-hand member of another branch road of co-planar waveguide signal wire and Pt/Au thermocouple arm join by the AlGaAs thermopair arm of Ohmic contact and lower end respectively, and the right-hand member of Pt/Au thermocouple arm ground roll lead wire and earth wire together links to each other, and the co-planar waveguide ground wire links to each other with pad.

Distinguish whether to be the standard of this structure as follows:

(a) input of power is to adopt co-planar waveguide to realize,

(b) measurement of power is to adopt thermopair to realize, and its impedance and co-planar waveguide coupling

(c) realize by monolithic integrated microwave circuit technology,

Satisfy above three requirements and promptly can be considered direct-type MEMS microwave power detector.

Beneficial effect:, the research and development of such device only are confined to scientific research field for a long time because the singularity of microwave power MEMS sensor construction.Microwave power MEMS sensor application exists and a series of obstacles such as incompatible, the repeatable poor reliability of main flow technology, production cost height in the large-scale production of integrated circuit.Direct heating terminal type MEMS microwave power detector structure among the present invention, the thermoelectric (al) power sensor construction of traditional waveguide form and the thinking restriction of technology have been broken through, searched out can with the integrated implementation method of simple digital-to-analog circuit, repeatable reliability all is greatly improved, and production cost significantly reduces.And this sensor has following principal feature: one, the frequency of this metering system and input and waveform are irrelevant, so entire device particularly terminator and frequency-independent; Two, can adopt the manufacturing of GaAs MMIC (monolithic integrated microwave circuit) technology, thereby realization and digital-to-analog circuit is simply integrated.Three.Specific volume is littler mutually with the indirect type microwave power detector, and precision is higher.Therefore, it is good to have the linearity, and frequency band range is wide, power precision height, and response speed is fast, can measure advantages such as smaller power.The present invention has well solved the variety of issue that the thermoelectric (al) power sensor of traditional waveguide form of above mentioning is run into, and is easy to realize high reliability, high duplication, the low production cost of device, satisfies simple integrated requirement well.Therefore, directly heat terminal type MEMS microwave power detector structure and have using value and vast market potentiality preferably.

Description of drawings

The vertical view of the direct heating terminal type MEMS microwave power detector structure that the GaAs MMIC technology that is based on Fig. 1 realizes.

Fig. 2 be among Fig. 1 A-A to the sectional structure synoptic diagram.

Fig. 3 be among Fig. 1 B-B to the sectional structure synoptic diagram.

Fig. 4 be among Fig. 1 C-C to the sectional structure synoptic diagram.

Fig. 5 is under the fixed frequency condition, output voltage and power concern synoptic diagram.

Fig. 6 is under the constant power condition, output voltage and frequency concern synoptic diagram.

Wherein have: substrate 1, co-planar

waveguide ground wire

2,3, co-planar waveguide signal wire 4, Pt/

Au thermocouple arm

5,6, AlGaAs

thermopair arm

7,8,

pad

9,10,11,12,13, Ohmic contact 14,16,17, medium 15.

Specific embodiments

We have designed implementation based on GaAs MMIC technology direct heating terminal type MEMS microwave power detector structure of the present utility model.Utilize thermopair to serve as terminator based on the direct heating terminal type MEMS microwave power detector structure that GaAs MMIC technology realizes, to be heat by the Conversion of energy of importing on the co-planar waveguide, the mode that is converted into voltage again records the size of microwave power, and structurally this sensor comprises substrate 1, co-planar

waveguide ground wire

2,3, co-planar waveguide signal wire 4, Pt/

Au thermocouple arm

5,6, AlGaAs

thermopair arm

7,8,

pad

9,10,11,12,13, Ohmic contact 14,16,17, medium 15; Wherein, AlGaAs

thermopair arm

7,8, medium 15 are located immediately on the substrate 1, co-planar

waveguide ground wire

2,3, co-planar waveguide signal wire 4 are positioned in the middle of the medium 15, and co-planar

waveguide ground wire

2,3, co-planar waveguide signal wire 4 are connected by

pad

9,10,11,12,13 draws; The left end of co-planar waveguide signal wire 4 connects pad 10, right-hand member connects two branch roads, and wherein a branch road connects Pt/Au thermocouple arm 5, the following termination Ohmic contact 14 of the other end of Pt/Au thermocouple arm 5, the following termination AlGaAs thermopair arm 7 of Ohmic contact 14, AlGaAs thermopair arm 7 joins with pad 12; The lower end of the right-hand member of another branch road of co-planar waveguide signal wire 4 and Pt/Au thermocouple arm 6 join by the AlGaAs thermopair arm 8 of Ohmic contact 16,17 and lower end respectively, the right-hand member of Pt/Au thermocouple arm 6 ground roll lead wire and earth wire 2 together links to each other, and co-planar waveguide ground wire 2 links to each other with pad 12.

Concrete processing step of the present utility model and parameter are as follows:

1) prepares GaAs substrate (400um)

2) deposit AlGaAs (0.8um)

3) ion injects the (n=10 that mixes ¹⁷Cm ^-3)

4) photoetching AlGaAs and etch the thermopair arm

5) deposit AuGe eutectic, Ni and Au,

6) photoetching and etch the Ohmic contact figure

7) high-temperature thermal annealing forms Ohmic contact

8) deposit SiON dielectric layer.

9) depositing metal and make co-planar waveguide by lithography and portion of hot galvanic couple arm

10) dielectric layer deposited.

11) make pad

In addition, note also some problems in the whole technical proposal, comprising: the resistance of thermopair must be very accurate, so the control of size is extremely important.In addition, in order to strengthen the mechanical stability of microcomputer thermoelectric pile, the distance between its nonmetal arm must equate; The roughness of the etching surface of co-planar waveguide has very big influence to the performance of co-planar waveguide, and this has just proposed than higher requirement to etching process, and the quality of etching effect is crucial to whole sensor.

This directly heats the technological process of terminal type MEMS microwave power detector to make a general survey of whole realization, does not wherein introduce any complicated special technology, and is compatible mutually with GaAs MMIC technology fully.Therefore, the direct heating terminal type MEMS microwave power detector structure of using among the present invention can realize the commercial application of power measurement structure in integrated circuit, and then promotes the development of whole IC industry.

Claims

1, a kind of direct heating terminal type micro electronic mechanical system microwave power sensor, it is characterized in that utilizing thermopair to serve as terminator, to be heat by the Conversion of energy of importing on the co-planar waveguide, the mode that is converted into voltage again records the size of microwave power, structurally this sensor comprises substrate (1), co-planar waveguide ground wire (2,3), co-planar waveguide signal wire (4), Pt/Au thermocouple arm (5,6), AlGaAs thermopair arm (7,8), pad (9,10,11,12,13), Ohmic contact (14,16,17), medium (15); Wherein, AlGaAs thermopair arm (7,8), medium (15) are located immediately on the substrate (1), co-planar waveguide ground wire (2,3), co-planar waveguide signal wire (4) are positioned in the middle of the medium (15), and co-planar waveguide ground wire (2,3), co-planar waveguide signal wire (4) are connected by pad (9,10,11,12,13) draws; The left end of co-planar waveguide signal wire (4) connects pad (10), right-hand member connects two branch roads, wherein a branch road connects Pt/Au thermocouple arm (5), the following termination Ohmic contact (14) of the other end of Pt/Au thermocouple arm (5), the following termination AlGaAs thermopair arm (7) of Ohmic contact (14), AlGaAs thermopair arm (7) joins with pad (12); The lower end of the right-hand member of another branch road of co-planar waveguide signal wire (4) and Pt/Au thermocouple arm (6) join by the AlGaAs thermopair arm (8) of Ohmic contact (16,17) with the lower end respectively, the right-hand member of Pt/Au thermocouple arm (6) ground roll lead wire and earth wire (2) together links to each other, and co-planar waveguide ground wire (2) links to each other with pad (12).