Preparation And Modification Of Indium Oxide Thin Film Transistors

As a switch and driving device of flat panel displays,the thin film transistors(TFTs)are of great significance to the display technology.At present,the display technology shows the tendency of developing high-resolution,large-size,high-drive current,transparent,and flexible.Further application of traditional silicon-based TFTs in flat panel display is limited due to their various disadvantages(such as low mobility for amorphous silicon TFT,poor uniformity for polycrystalline silicon TFT,and poor transparency in visible region for both).Compared with the traditional silicon-based TFTs,the metal oxide TFTs exhibit the advantages of excellent electrical performance,high transparency,good uniformity and low temperature fabrication.It is expected to replace the silicon-based TFTs for next-generation display technology,which attracted wide interest for researchers worldwide.In this thesis,high-performance indium oxide TFTs were prepared by electrospinning and solution process.The main investigations of this thesis are as follows:1.In₂O₃ nanofibers TFTs were prepared by electrospinning,and the electrical performance of the In₂O₃ nanofibers TFTs could be manipulated by a low-cost and simple plasma treatment process.The influence of the atmosphere,plasma power and treatment time of the plasma treatment on the electrical performance of the In₂O₃ TFTs were systematically studied.It was found that the best electrical performance of In₂O₃nanofiber TFTs could be obtained under the treatment of oxygen plasma power of 120W for 5 min.In order to further reduce the operating voltage and improve the electrical performance,high permittivity(?)Zr Ox thin layer was used as the dielectric layer,the In₂O₃/ZrOx TFTs exhibited higher electrical performance with an on/off current ratio(I_on/I_off)of 3.4×10⁷,a near-zero threshold voltage(V_TH)of 1.34 V,and a high field-effect mobility (?) of 15.12 cm²/Vs.2.The TFTs with bilayer of In₂O₃:O/In₂O₃:A were prepared by sol-gel method.In the bilayer structured device,the channel layer consists of a carrier injection layer and a carrier transport layer.The In₂O₃ thin film annealed in oxygen atmosphere(In₂O₃:O)with dense indium oxide lattice structure is selected as the carrier transport layer,which avoids the influence of defect states.The In₂O₃ thin film annealed in air(In₂O₃:A)acts as the carrier injection layer due to its high carrier concentration.Through the design of two-layer structure,the carrier transport layer with high carrier concentration and low defect states is formed in In₂O₃:O/In₂O₃:A TFTs at 280?,and the high electrical performance and high stability were obtained.