Molecular Dynamics Study Of Dewetting Growth Of Au Nanoparticle Array On Pre-patterned Substrate

Recently,many experimental and theoretical studies have been carried out on the dewetting of metal films to grow Au nanoparticle array(nanoarray)on the solid pre-patterned substrate surface,and many meaningful results have been obtained.However,the growth conditions to obtain high quality Au nanoarray with uniform particle size,appropriate particle spacing and ordered particle distribution have not been well studied.The dynamic process of dewetting of Au thin films on solid substrates is very complicated.The growth of Au nanoarray is not only related to temperature,but also to the property of substrate.In recent years,the discussion of growth conditions to influence the growth of Au nanoarray is a hot issue in the field of nanomaterials.In our work,we investigated the effect of the substrate and the temperature on the growth of Au nanoarray on a solid-patterned substrate by dewetting Au liquid film using atomic simulation technique.The patterned substrate was constructed by grouping two types atom(C1 and C2)in the graphene-like substrate and introducing two different interaction potentials between Au and C1(C2)atoms of substrate.Our simulation results demonstrated that the R and D parameter of substrate play a strikingly different influence on the growth of the Au nanoarray.The degree of order of the nanoarray increases first before it reaches a peak and then decreases with increasing R at fixed D.However,the degree of order increases monotonously as increasing D and reaches a saturated value beyond a critical value of D for a fixed R.Interestingly,a labyrinth-like structure appears during the dewetting process of the Au film.The simulation results also indicated that the temperature play an important role on controlling the properties of nanoarray.An appropriate temperature leads to an optimized nanoarray with uniform grain size and well-ordered particle distribution.In addition,we also investigated the effect of the strip substrate on the Au nanoparticles arrays.With the increase of LID,the number of Au nanoparticles decreases first and then increases.Au nanoparticles resides in the stripe(C1)region,and when LID is large,the number Au nanoparticles located in the stripe(C1)region increases gradually.At the same time,the size of nanoparticles becomes uniform and the length of the particles along the stripe direction decreases gradually.These results are important for understanding the dewetting behaviors of metal films and the growth of highly ordered metal nanoarrays using a solid-patterned substrate method.Additionally,it is also helpful to understand the growth of nanowire and nanofiber in the field of plasma,magnetic memories,DNA detection and the catalyst.