Love wave gas sensor

Abstract

The invention provides a love wave gas sensor which comprises a piezoelectric substrate, an input interdigital transducer, an output interdigital transducer and sensitive films, wherein the input interdigital transducer and the output interdigital transducer are deposited on the surface of the piezoelectric substrate, the sensitive films are covered on the piezoelectric substrate, the input interdigital transducer and the output interdigital transducer, the sensitive films are semiconductor-type gas sensitive material layers, the input interdigital transducer excites and spreads sound waves inthe piezoelectric substrate, the output interdigital transducer is used for receiving the sound waves, the characteristics of the sound waves can be changed after a loaded measured object reacts withthe sensitive films, and the characteristic conclusion about the measured object is acquired through detecting the changes. The love wave gas sensor can overcome the defect of lower detection lower limit of an existing semiconductor-type sensor, improves the performance of the sensor from the aspect of detection means, and realizes a gas detection function with high sensitivity and stability by combining the structure of a love wave sensor with an existing semiconductor-type solid gas sensitive film technology.

Description

technical field [0001] The invention relates to a Love-type acoustic wave (abbreviated as Love-wave) sensor, in particular to a Love-wave gas sensor using a semiconductor-type gas-sensitive material. Background technique [0002] Since 1964, the first gas sensor was developed by Wickens and Hatman using the oxidation-reduction reaction of gas on the electrode. In 1982, Persaud of the University of Warwick in the United Kingdom proposed the structure of using a gas sensor to simulate the animal olfactory system. Sensors develop rapidly and are used in various occasions. Gas sensors mainly include semiconductor sensors (resistive and non-resistive) (Sensor World, 2001, "Research Progress of Several Common Gas Sensors"). Existing gas detection devices mainly use the changes in resistance, capacitance and current caused by the contact between the gas-sensitive film and the gas to be measured to determine the gas concentration. At the same time, there are a lot of researches on...

AI Technical Summary

Problems solved by technology

However, during the experiment, it was found that in this kind of sensor device, the formation of organic chemical sensitive film is easily affected by many factors such as temperature, humidity, oxidation, static electricity and pressure, and the stability is not good, which limits the existing acoustic sensor. Application Range of Surface Wave Sensors

[0004] It can be seen that in practical applications, there has not been a surface acoustic wave gas detection device with high sensitivity and good stability.

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