Research On Terahertz Metamaterial Biosensor Based On Parylene-C Flexible Substrate

In recent years,with the development of micro and nano processing technology,the cost and difficulty of terahertz band metamaterial devices were more in line with the requirements of technical development,so it had been widely concerned around the world.It had made great achievements in the fields of biomedicine,security and communication.The metamaterial biosensor based on terahertz time-domain spectrometry(THz-TDS)had the advantages of off-label,non-contact,no damage and in vitro detection.At the same time,the combination of microfluidic technology and bio-modification technology also promoted the development of terahertz wave metamaterials in micro and specific detection and provided new detection means for detection in biomedical field.In order to improve the sensitivity and detection limit of terahertz metamaterials,Parylene-C flexible substrate was used to make biomaterial biosensors.Its advantages were that low dielectric constant of flexible substrate can reduce material loss and enhance the sensitivity of metamaterial biosensors.The foldability of flexible substrate expanded the application scenarios of terahertz biomaterial biosensors.The main research content was the development and preliminary verification of terahertz metamaterial biosensor based on Paraylene-C flexible substrate,as follows:(1)Theoretical analysis of terahertz metamaterial biosensor.This paper mainly discussed the material and operational principle of the metamaterial sensor.Based on Fermat's principle and generalized Snell's law,the optical principle of the transmission resonance peak was derived.LC coupling resonance mechanism analyzed the operational principle of the sensor.(2)Design the terahertz metamaterial biosensor.A new type of terahertz metamaterial biosensor was designed,which was based on the elliptical open-loop structure and the "?" shape structure.The design structure was modeled and simulated by electromagnetic simulation software.The effects of structural parameters and substrate material parameters on the sensing properties of metamaterials were obtained.(3)Terahertz metamaterial biosensor was prepared.The chemical vapor deposition(CVD)method was used to prepare flexible substrate(Parylene-C)films.The preparation process of Parylene-C films was improved to make the flexible films flat and free of particles,to ensure the results of metamaterial devices.Use semiconductor technology to realize the preparation of metamaterial structure on the surface of Parylene-C film.At the same time,the microfluidic channel was fabricated by PDMS and the microfluidic terahertz metamaterial biosensor was integrated with the metamaterial device.The repetition rate of terahertz biomaterial biosensor was more than 95%.(4)Terahertz metamaterials was used for device verification.Cancer markers(AFP antigen)was selected for detection and validation.The combination of antibody and antigen was verified by the shift of resonance peak of transmission spectrum.The results verify the feasibility of terahertz metamaterial biosensor,which was applied to cancer markers detection.