Study On The Preparation Of Stannous Oxide Crystal And Its Electrical Properties

Recent studies had shown that stannous oxide?Sn O?crystals had higher hole carrier concentration and hole mobility,and it was a p-type metal oxide semiconductor with great development potential.However,the currently prepared Sn O crystal had a small geometric size and poor stability,which made its future research and application greatly restricted.Therefore,in order to solve the above problems,this paper focused on the research work in the preparation of Sn O crystals,crystal stability and electrical properties etc.First of all,in this paper,Sn O crystals were prepared by thermal evaporation,and a set of four factors and five levels(L₂₅?5⁴?)experimental schemes were designed by orthogonal test design.The effects of experimental factors such as the center temperature of the furnace,the position of the deposition zone,the deposition time,and the flow rate of Ar gas on the crystal growth were investigated.The experiment showed that the center temperature of the furnace was the main influencing factor.Under the experimental condition of 600?/12 cm/0.5 h/20 sccm,a thin layer of dendrites was formed.The crystal composition was Sn O,which it was preferentially oriented along the?201?crystal plane,and it had strong chemical activity and was easily oxidized.In addition,there were also generated square and linear crystals,and the crystal composition was tin-oxygen mixed phase?Sn Ox?.Secondly,this paper further used hydrothermal synthesis to prepare Sn O crystals.Large-sized and single-phase Sn O crystals were prepared by constant temperature heating.Sn O crystal growth had a clear preferential orientation,preferential grown along the?001?crystal plane on the horizontal plane and preferential grown along the?101?crystal plane on the vertical plane.By researching the thermal stability of Sn O crystals,which was found that Sn O began to oxidize at 450?.When the temperature rose to 900?,the crystal was completely oxidized to Sn O₂.Due to the thermal effect,the crystal lattice constant changes along the a,b,c axis direction at300?,600?and 900?.Through the investigation of the electrical properties of Sn O crystals,it was found that Sn O crystals had p-type semiconductor properties.The carrier concentration was 1.23×10¹⁵/cm³,the hall mobility was 4.86 cm²/Vs,the resistivity was 1.05×10³?cm and the work function was 5.07 e V.Finally,Sn O crystal was mechanically stripped to obtain a thin Sn O crystal with a thickness of less than 30 nm,which was used as an active layer in the field effect transistor.The device preparation adopted the electron beam lithography and the in-situ microscope masking.After annealed,the device which prepared by the in-situ microscope masking,had field effect characteristics.The field effect mobility of the device was 1.69×10^-3 cm²/Vs,the current switching ratio was 5.91×10² and the sub-threshold swing was 1.39 V/dec.