Based On The Preparation And Properties Of ZnSnO Nanofiber FETs

One-dimensional?1D?nanofibers have been considered as important building blocks for nano-electronics due to their superior physical and chemical properties.However,among so many fabrication techniques,electrospinning technique provides a facile,scalable and low-cost route for the fabrication of uniform and continuous distributed nanofibers.At the same time,field-effect transistors?FETs?have been widely applied in flat-panel display technologies due to their simple structure and excellent properties.Metal oxide?MO?semiconductors have become one of the key components in flat-panel displays due to their high carrier mobility,excellent optical transparency,and electrical stability.Among MO semiconductors developed to date,indium-based oxides have been extensively studied as channel components in high-performance electronic devices.However,the limited supply of indium,along with the huge demand for non-toxic materials,has motivated the scientific and industrial community to search for indium-free alternatives.Zinc-tin oxide?ZnSnO?is one of the most promising indium-free MO semiconducting candidates in terms of price,supply and toxicity.Therefore,in this thesis,we report on the fabrication and study of the FETs based on ZnSnO nanofibers by electrospinning and investigate the possible applications.Firstly,we fabricated the high quality ZnSnO nanofibers by using electrospinning,and the effects of composition ratio of Zn to Sn on the physical,chemical and electrical properties of Zn_xSn_1-xO?x=0,0.1,0.3,0.5,0.7,0.9,1?nanofibers were systematically investigated.The FETs based on optimal Zn_0.3Sn_0.7O NFNs were integrated on high-?ZrO_x dielectric layers.The as-fabricated FET exhibits improved electrical performance,including a high?_FE of 7.8 cm² V^-1 s^-1,a small SS of 81 mV dec^-1,and a large I_on/off of¹0⁷.Finally,to explore the possibility of low-voltage Zn_0.3Sn_0.7O NFNs/ZrO_x FETs toward logic applications,a resistor-loaded inverter was constructed by connecting the FETs with a resistor in series.A maximum gain(defined as-?V_OUT/?V_IN)of 11 at V_DD=4 V is achieved.Secondly,to further explore the properties of ZnSnO?Zn:Sn=3:7?nanofibers annealed in various annealing condition?e.g.temperature,ambient atmosphere?,the FETs based on ZnSnO NFNs/SiO₂ annealed in different temperatures?e.g.400 ^oC,450 ^oC,500 ^oC,550 ^oC?under different atmospheres?e.g.,air,oxygen?were integrated and examined,respectively.The transfer characteristics indicates that,compared with the FET based on ZnSnO annealed in the air,the FET based on ZnSnO annealed in the oxygen exhibits notably improved electrical performance and operational stability.Finally,the FETs based on ZnSnO were integrated on ZrO_x and exhibit superior electrical performance,including a?_FE of 21.58 cm² V^-1 s^-1,an I_on/I_off of¹0⁸.Based on these achievements,ZnSnO nanofibers represent great potential for future high-performance nano-electronics and related applications by adjusting the stoichiometry of the composition in the precursor solution and the annealing condition?e.g.temperature,ambient atmosphere?of devices.