Preparation And Properties Of Cu₂S Thermoelectric Thin Film And It's Application In Thin Film Field Effect Transistors

Thermoelectric?TE?materials can directly convert thermal energy into electrical energy.Due to its high reliability,quiet operation,conformity to composite energy saving and environmental protection,it has recently received great attention from researchers around the world.The thermoelectric material with higher performance currently for commercial use are generally composed of expensive and toxic heavy metal alloys or compounds.Therefore,in the field of thermoelectric material research and practical applications,the latest research topic include issues such as finding and developing thermoelectric materials with excellent thermoelectric properties without heavy and toxic elements by using the the latest research findings in materials science.In recent years,Cu₂S semiconductor materials have been widely used in the fields of thermoelectric material preparation and new field effect transistor development due to their abundant reserves,pollution-free,cheap and easy to prepare,and have been highly valued by the world materials science community.This thesis aims at adopting simple and feasible chemical reaction method and RF magnetron sputtering technology to prepare Cu₂S thin film on different substrates,thermoelectric properties and experimental research on the preparation and characteristics of Cu₂S thin film field effect transistor.It is expected to do some basic exploration for the research and development of Cu₂S semiconductor materials in the next generation of new microelectronics,spintronics and valley electronics devices.The main research work carried out in the thesis is as follows:?1?A simple and feasible chemical direct reaction method was used to directly prepare a cuprous sulfide?Cu₂S?semiconductor film on a copper substrate by adjusting the content of sulfur powder in the reactant,and the film prepared under different conditions by SEM,XRD,EDX,etc.The crystal structure and surface morphology of the sample were characterized.The thermoelectric properties of the prepared Cu₂S thin films were tested and analyzed by a thermoelectric property tester.At the same time,the paper also analyzed the growth mechanism of Cu₂S thermoelectric thin film materials.?2?Thermoelectric thin films were prepared by RF magnetron sputtering method with Cu₂S high purity ceramic target under different conditions.The Cu₂S thermoelectric film samples under different conditions were analyzed by SEM,XRD and thermoelectric detection.The factors affecting the Seebeck coefficient,thermoelectric figure and thermal conductivity of the prepared Cu₂S thermoelectric film samples were both compared and compared.The thermoelectric properties of Cu₂S thermoelectric film samples prepared by chemical direct reaction method and RF magnetron sputtering method were also compared.?3?Cu₂S thin film FETs were fabricated by magnetron sputtering.The IV characteristics of FETs fabricated under different conditions were studied.By changing the channel thickness and channel width of the device,the effects of device structure,applied gate voltage,source-drain bias,etc.on the transmission characteristics of the device were analyzed.The research results provide a certain foundation for the next step of the in-depth implementation of Cu₂S thermoelectric integrated control devices.