Control Of Annealing Temperature And Aluminum Doping Concentration On The Electrical Properties Of Indium Zinc Oxide Nanofiber Field Effect Transistors

One-dimensional metal oxide semiconductor materials(such as Zn O,In₂O₃,In Zn O,etc.)have attracted extensive research attention in the new generation of transparent electronic products and optoelectronics.In these materials,In₂O₃ is widely used as the channel layer of the field effect transistor due to its high carrier mobility,large area uniformity and reasonable electrical stability.However,a large number of oxygen vacancies generated by In₂O₃ make In₂O₃ nanofibers transistors usually suffer a high off-current and consequent a large negative threshold voltage as well as a large subthreshold swing amplitude.Doping zinc in In₂O₃ to form In Zn O can effectively inhibit the formation of oxygen vacancies and thus reduce the carrier concentration,however,due to thermal diffusion of the Zn element,In Zn O nanofibers usually exhibit a coarse surface and are discrete as disconnected segments caused by the overgrowth of In Zn O grain during high temperature,which seriously affect the electronic transmission.In view of the above problems,this thesis has carried out the following works and obtained the relevant results:1.High performance In Al Zn O nanofibers field effect transistors were fabricated by one-step electrospinning.With a small amount of Al doping,the carrier concentration is further suppressed,the off-current is reduced where the on-current is maintained at the same order of magnitudes,and a higher on/off current ratio is obtained.At the same time,when the NFs were annealed at 600 ^oC,the fracture phenomenon of In Zn O nanofibers is effectively improved,and the resulting In Al Zn O nanofibers are smooth and uniform,which is conducive to the effective electron transport.It is found that the In Al Zn O nanofibers field effect transistors prepared with 0.9%Al doping concentration has excellent electrical properties:high on/off current ratio of?10⁷,high carrier mobility of 10 cm²V^-1s^-1,and low threshold voltage of 1 V.2.In this work,we prepared high performance In Zn O nanofibers field effect transistors at low annealing temperature by comprehensively applying combustion synthesis method and electrospinning technique.The In Zn O nanofibers field effect transistors annealed at 400 ^oC has a high on/off current ratio(10⁶),a threshold voltage close to 0 V,and a satisfactory mobility(0.47 cm²V^-1s^-1).These results indicate that In Zn O nanofibers field effect transistors have great potential applications in future electronic devices.