Preparation And Electronic Properties Of Piezopotential Gated Two-dimensional Composite Thin Film FETs

Piezoelectric gated field effect transistor(FET)is an emerging research field.Its basic principles are mainly based on piezoelectric effect,field effect and coupling between semiconductor materials.The preparation of materials requires both piezoelectric and semiconductor properties and can be applied to Microelectronics,sensing and other fields.Therefore,gated piezoelectric field effect transistors have become a relatively new research field in piezoelectric electronics.The gated piezoelectric field effect transistor uses the piezoelectric potential generated in the crystal to act on the gate of the traditional field effect transistor to control and adjust the carrier transfer characteristics between the source and drain electrodes,and then control the current and voltage signals and apply them For microelectronics and microelectromechanical equipment,this has potential applications in microelectromechanical systems,nanorobots,human-machine interfaces,and sensor photoelectric conversion.AlN has a wide band gap(6.2eV),good chemical and thermal stability,and its C axis also has excellent piezoelectric properties.The SnO film is a kind of film with bipolar conductivity.Because of its unique conductivity,it will be used in channel thin film field effect transistors and CMOS devices.ZnO is a direct band gap semiconductor material with a hexagonal wurtzite structure.Under the promotion of Professor Wang Zhonglin^[1],it has shown excellent characteristics in piezoelectric,optoelectronic,pressure-sensitive,gas-sens itive and other aspects.In this paper,using the piezoelectric properties of AlN film,combined with SnO and ZnO semiconductor films,a two-dimensional composite film AlN/SnO piezoelectric gated FET was fabricated.The research results can be used to explore the application of piezoelectric materials in the field of micro-nanoelectronic devices.And the results can be as an experimental basis for research and development of a new generation of integrated circuit nanoelectronic devices.The main research work of this thesis is as follows:1.Using magnetron sputtering technology and high-purity target materials to prepare two-dimensional few-layer SnO film on Si/SiO₂ substrate,and prepare AlN/SnO composite film on SnO film deposition,using XRD,EDS,SEM,Dektak Analytical instruments such as step meter characterize and analyze the morphology,composition,crystal structure and thickness of the film.2.Under different deposition conditions and device design parameters,the bottom gate type intrinsic SnO film channel was prepared by using masked magnetron sputtering technology,and a layer of AlN semiconductor piezoelectric film was deposited on it to prepare AlN/SnO piezoelectric gated field effect transistor.The Keithley4200-SCS semiconductor characteristic tester was used to test and compare the ? characteristics,output characteristics,transfer characteristics,response time,sensitivity of different devices,and found the best preparation conditions and the best performance AlN/SnO piezoelectric Gated field effect transistor devices.3.Using Keithley4200-SCS semiconductor characteristic tester to analyze the electrical properties of piezoelectric gated devices prepared under optimal conditions,the results show that the AlN/SnO piezoelectric gated two-dimensional composite thin film field effect transistors prepared in this paper have high Sensitivity and fast response speed,it can be applied to pressure sensing equipment.4.In order to fully prove the usability of the piezoelectric gated two-dimensional composite thin film field effect transistor device prepared in the thesis.We also prepared n-type AlN/ZnO piezoelectric gated field effect transistor devices,and performed lattice orientation,element analysis and surface morphology characterization of the prepared ZnO film and AlN/ZnO composite film,using the Keithley4200-SCS semiconductor characteristic tester compares and analyzes the ? characteristics of bottom-gate intrinsic ZnO thin film field effect transistors and AlN/ZnO piezoelectric gated field effect transistors.The optimal preparation conditions were found,the AlN/ZnO piezoelectric gated field effect transistor device with the best performance was fabricated,and its electrical performance was analyzed and studied.The study found that whether it is a p-type field effect transistor device or an n-type device,the prepared piezoelectric gated field effect transistor has higher sensitivity and faster response speed,indicating that the device prepared in this article can be used in pressure On the sensing equipment,the research results can provide experimental basis and data reference for the new generation of integrated circuit nanoelectronic devices.