Synthesis Of Two-Dimensional WSe₂ And Assisted Growth

In recent years,two-dimensional（2D）materials such as graphene have attracted much attention due to their unique properties.With the rise of two-dimensional materials,transition metal dichalcogenide compounds（TMDC）monolayer molecules have become a new area for exploring two-dimensional semiconductor materials.Many researchs have shown that it has great application value in the fields of electronics and optoelectronics.However,due to the immature preparation method,there are still some challenges in its practical application.In response to this,this paper has studied in detail the preparation method of CVD,and discussed the auxiliary growth of WSe₂ and related photoelectric properties.The details are as follows:1.The optimal window of single layer WSe₂ growth conditions was explored by using the control variable method:（1）The effect of H₂ on the growth of single-layer WSe₂:After adding H₂,it effectively promotes the reduction and selenization reaction,while reducing the formation of intermediate products and by-products.The single-layer of WSe₂ is grown on the substrate.（2）The effect of temperature and growth time on the growth of single-layer WSe₂:when the temperature is 1000℃and the growth time is 13 minutes,60μm triangular single-layer WSe₂ is successfully grown.（3）Explore the growth mechanism of regular hexagon,regular triangle and truncated triangle WSe₂.2.The effect of KCl on the growth of WSe₂:The addition of KCl to WO₃accelerated the sublimation and selenidation rate of WO₃,and the monolayer WSe₂grown on the substrate is significantly more and denser.When KCl:WO₃ was 1:10,WSe₂ thin films with good surface uniformity and high crystal quality are grown at 234μm.At the same time,Raman、SEM、AFM and other characterization techniques were used to prove that the grown samples are single-layer WSe₂with high-quality.3.The introduction of Te powder into the precursor could effectively reduce the growth temperature of WSe₂,and successfully achieve the low temperature growth of WSe₂.Figure 43,table 2,references 46.