Preparation Process And Surface Energy Calculation Of CoSi₂ Thin Films

Magnetron sputtering is a kind of physical vapor deposition method,which can be used to prepare metals,semiconductors,insulators and other materials.It has been developed since the 1970s,so the scientific nature of the experiments has been widely confirmed.There has been no previous research on theoretical calculation of CoSi₂film and its surface,no systematic research on preparation of CoSi₂ film by magnetron sputtering,and no research on the optimal preparation process of CoSi₂film by magnetron sputtering.The significance of this study lies in the systematic exploration of the magnetron sputtering preparation process of CoSi₂ thin film,so as to prepare CoSi₂ thin film with a single phase and a continuous and smooth surface,which provides more possibilities for the application of CoSi₂ thin film in integrated circuit devices.Firstly the basic properties of CoSi₂ are introduced in detail,and the research status of CoSi₂ thin films is introduced comprehensively.The content,purpose and method of this paper are put forward.the properties of CoSi₂ thin films with different thickness in[111]orientation,the change of surface bond length,the energy band and density of states of different thickness films and blocks were calculated by first principles.The effects of film thickness on the surface structure,energy band,density of states and magnetic properties of CoSi₂ thin films were studied.The surface energies of(111),(220),(311),(400),(331)and(422)crystal face of CoSi₂ films were calculated,and the surface energies of CoSi₂ films with different crystal face were compared.The results show that when the film has a two-layer atomic structure,the thickness of the film will affect the surface structure of the film,as well as the energy band,density of states and magnetic properties of the film.When the thickness increases,the influence can be ignored.Among the CoSi₂ films with different crystal face,the lowest surface energy of(111)crystal face is 885.45 e V/nm²,and the structure is the most stable.In the process of experimental preparation,there may be preferential growth.In the experiment,based on the results of calculation,single crystal silicon with(111)crystal plane was selected as the substrate,Co-Si compound was prepared by magnetron sputtering and high vacuum annealing,the thickness of Co film was determined by controlling the sputtering time,and the cross section of the film was observed by SEM.The deposition rate of Co film by DC sputtering was 6 nm/min.CoSi₂ thin films with different heat treatment parameters and sputtering process were prepared.The surface morphology and structure of CoSi₂ thin films were characterized by X-ray diffraction,Raman spectroscopy and scanning electron microscopy.The effects of heat treatment temperature,heat treatment time,sputtering pressure,Ar gas flow rate and sputtering power on the formation,structure and morphology of CoSi₂ thin films were investigated.Finally,16 groups of different preparation parameters were generated under the conditions of 5 factors and 4 levels by using orthogonal experiment method and orthogonal assistant software.CoSi₂ thin films were prepared and the preparation parameters were optimized.Finally,the preparation parameters were optimized and the optimum preparation parameters were obtained as follows:sputtering power of 75W,sputtering pressure of 2.0 Pa,Ar gas flow rate of 50 sccm,heat treatment temperature of 720?,and heat treatment time of 5.0 h.The most important factor affecting the preparation of CoSi₂ films is the heat treatment temperature.