Preparation And Performance Study Of IGZO TFT Biosenso

As a chronic neurodegenerative disease,Parkinson’s disease（PD）has no effective treatment at present.Only drug and non-drug intervention methods can be used to delay the disease in the early stage,and the commonly used methods have the disadvantages of expensive,time-consuming and complex process.Nowadays,Thin Film Transistor（TFT）biosensors have attracted wide attention due to a series of advantages such as fast response,low cost,easy integration,and high sensitivity.The use of TFT biosensors undoubtedly provides a new detection method with low cost,fast response and high sensitivity for the early treatment of PD.In this study,an extended gate indium gallium zinc oxide thin-film transistor（IGZO EGTFT）biosensor was designed and fabricated to detectα-synuclein（α-Syn）,a pathological marker of Parkinson’s disease,at different concentrations after functionalized.The effect of pH on the TFT biosensor was further studied.The main research contents of this paper are as follows:1.The preparation of the IGZO EGTFT biosensor.The preparation of biosensor includes the preparation of IGZO TFT,ITO extended gate,ITO sensing platform and surface functional.In this study,IGZO EGTFT biosensors were prepared by sol-gel,ALD,thermal evaporation and magnetron sputtering and their properties were optimized.The electrical properties of the prepared IGZO TFT are as follows:at the V_DSof 1 V,The switching current ratio,subthreshold swing and threshold voltage(V_TH)of the IGZO TFT are 7.46×10⁴,53.9 m V dec^-1and 3.2 V,respectively.2.The response ofα-Syn concentration to the IGZO EGTFT biosensor was explored.The sensing platform was functionalized to enable the IGZO EGTFT biosensor to be specifically selected forα-Syn.The functionalized ITO sensing platform was stably fixed on the surface of the sensing platform by AFM analysis and FITC fluorescein antibody labeling.Subsequently,according to the concentration ofα-Syn in human cerebrospinal fluid and blood,the test solution of 1 pg to 10 ng m L^-1α-Syn was diluted to explore the effect of different concentrations ofα-Syn on the IGZO TFT biosensor.3.The effects of pH and different specific surface area sensing platform on IGZO EGTFT sensor was explored.On the basis of the previous IGZO EGTFT biosensor,the surface of the ITO sensing platform was treated with a layer of hydroxyl group through an oxygen plasma cleaner,so as to achieve the role of pH detection in the treatment solution.The device was tested with distilled water diluted out of five tested solutions with pH 4,6,8,10,12.In this experiment,two ITO sensing platforms were prepared by magnetron sputtering and electrospinning to explore the effects of ITO sensing platforms with different specific surface areas on detection of pH.