Two-end heated microwave power sensor

Abstract

A microwave power transducer of two-ends heating type is prepared as using GaAs as substrate, arranging a layer of AIGaAs film on said substrate, setting thermoelectric stack formed by a group of series-connected GaAs/AuGe thermocouple on AIGaAs film, using coplanar waveguide A on GaAs substrate as input transmission line of microwave signal to be measured and connecting coplanar waveguide with two parallel-connected DC heating resistances.

Description

technical field [0001] The invention realizes the microwave power measurement by replacing the microwave power with DC (low frequency) electric power, and belongs to the technical field of microelectronic devices. Background technique [0002] In microwave research, microwave power is an important parameter to characterize microwave signal characteristics. In microwave wireless application and measurement technology, the detection of microwave power is a very important part. The traditional power meter uses a waveguide power sensor, uses bismuth-antimony as a thermocouple, and uses a coaxial cable as a transmission line. Its main disadvantages are slow response, low burnout level, attenuators are used when measuring high power, and it cannot integrated into the circuit. [0003] In the past 20 years, with the rapid development of MEMS technology, foreign countries have proposed a terminal direct heating microwave power sensor based on MEMS technology. The nearby thermocou...

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Problems solved by technology

However, this sensor also has several serious shortcomings - because it is a single-ended heating structure, that is, only the microwave terminal resistor generates heat and conducts heat transfer to one end of the thermopile, so the accuracy of the measurement results will be affected by various heat losses. These heat losses include: after the microwave terminal resistance heats up, the heat is transferred to the thermopile due to the heat conduction loss of the terminal resistance and the thermopile to the substrate, the heat loss to the environment due to heat convection, and the heat loss to the environment due to heat radiation. Second, its manufacturing process is relatively complicated, and the various performance indicators of the sensor are very sensitive to its own structural parameters, and there are inherent contradictions between sensitivity and response time, sensitivity and noise, microwave performance and thermal performance. It cannot be solved, which brings great difficulty to designers; in addition, this single-ended heating power sensor only has one working mode, the use process is single, and its measurement results also need subsequent voltage-power Calibration process to get the size of the microwave power to be measured

Therefore, the design process of this microwave power sensor is not only more complicated, but also has high cost, poor reliability, consistency and stability of mass production, and is inconvenient to use.

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