A Study Of Electrochemical/FET-integrated Micro-nano Resonator Biosensor

Biosensor,especially affinity-based biosensor,is a fast-developing technology in recent years,and is of great meaning in many fields such as biology,chemistry,and health care.Attributed to the progress in micro-nano technology,biosensor becomes smaller and lighter,and has tendencies towards high-density integration,ultra-sensitive detection and smart system.Piezoelectric-based film bulk acoustic resonator(FBAR)sensor,as a biosensor based on microfabrication,has received great attention due to its small size,low power consumption,high sensitivity,compatibility with CMOS process,easy array-format integration for high-throughput detection,and so on.To address the great demands in chip-integrated affinity-based biosensor,this thesis explored FBAR biosensor a step further.Based on previous research investigations on QCM-SPR and QCM-FET as well as EQCM dual-sensor platforms,this thesis proposed a FET/electrochemical integrated FBAR sensing system on a single chip.We fabricated the chip,set up the measurement modules for both FET-FBAR and electrochemical-FBAR sensing platforms.The validity and praticability of the two platforms were proved by successfully detecting glucose concentration variation,DNA hybridization activity,self-assembled polymerization process and affinity-based antigen-antibody interaction.The main achievements of this thesis are listed in the following:1.A multi-mode sensing system on a single chip was proposed.Both electrochemical/FET and FBAR sensors were chip-integrated by sharing aluminum nitride thin film.The system assembles multiple sensing modes of electrochemistry/charge,gravimetry(mass),viscosmetry,and presents the ability to detect complex interfacial information.2.A single-chip-integrated electrochemical-FBAR sensing platform was proposed.The platform helped optimize growth of the affinity film by monitoring the interfacial mass changes,and successfully detected concentration variation of glucose by monitoring electric current from redox reaction as well as viscosity changes.3.A single-chip-integrated FET-FBAR sensing platform was proposed.The platform successfully detected the self-assembled polymerization process as well as antigen-antibody interaction.The platform had a deep insight of the intrinsic mechanisms of the above activities through comparative analysis of interfical charge and mass information.4.Graphene was transferred to FBAR surface as a functional layer,which enhanced the sensitivity of FBAR to two kinds of organic vapor.5.PVA was spin-coated onto FBAR surface as an ultra-thin absorption layer,which greatly improved sensitivity of FBAR to humidity changes.