Study On Interface Control Of Two-dimensional MoTe₂ Field-Effect Transistors

With the development of electronic information technology,artificial intelligence and the Internet of Things are widely used in various fields.Transistor,as the most basic element of its internal module,is an important research object.With the shrinking of the feature size of traditional silicon process transistors,the limits of Moore's Law are constantly approaching,and the resulting technical and economic constraints have promoted the exploration of new materials and devices.Two-dimensional materials represented by transition metal dichalcogenides(TMDs)have shown great potential due to their excellent performance,atomically-thin structure,and high surface to volume ratio.The interface characteristics of TMDs materials play a major role in the performance of the device,so the study of its interface control is of great significance.In this paper,molybdenum telluride(MoTe₂)field-effect transistors are used as the research object,and several stable and controllable interface control methods are studied.The main research contents of this paper are as follows:(1)The characteristic changes of MoTe₂ materials under different treatments are studied.The material interface defects are removed by annealing treatment without changing the material characteristics;the material is oxidized by oxygen plasma treatment and the oxide Mo O_x is formed on the surface.(2)MoTe₂ field-effect transistors are fabricated,which showing bipolar characteristics dominated by p-type.Introduce oxygen plasma treatment to control different types of interfaces of the device:The transistors with the oxidized MoTe₂/adsorbate interface are fabricated,and the n-type characteristics show that the treatment had electron doping on the channel;the transistors with the oxidized MoTe₂/metal contact interface are fabricated,showing good bipolar characteristics and migration The mobility has increased by 1 to 2 orders of magnitude,indicating that the device contact is improved;the transistors with oxidized MoTe₂/adsorbate and the metal contact interface are fabricated,and the n-type characteristics show that the oxidation-treated MoTe₂/adsorbate interface plays a leading role in the performance of the device.(3)The effect of subsequent annealing on the treated device is studied,and the p-type characteristics show that annealing has a certain effect on the removal of channel oxides.The hysteresis phenomenon of the treated device is studied,and the research of DC and pulse mode shows the existence of trap effect in the device.