Analysis Of Three-dimensional Deposition Characteristicsof Chromium Atoms In The Straight Edge Diffraction Standing Wave Field

Atom lithography is a new technical of using laser standing wave field to convergence atomic grating and acquire periodic atomic deposition grating stripe in nanometer level.Considering the existence of deposition substrates,diffraction phenomena was appeared in laser standing wave field,and the laser standing wave field intensity distribution was affected,then the deposition nanometer grating structure was changed.Therefore,discussing the diffraction effect of deposition substrate in the process of laser standing wave field convergence atoms is of great significance.Based on the semi-classical model,the Chromium atomic three dimensional trajectory and deposition characteristics in laser standing wave field under the straight edge diffraction disturbance was analyzed,and the deposition grating was analyzed from the FWHM(Full Width at Half Maximum)and the Contrast.By discussing the different diffraction model,the diffraction produced by substrate was identified as straight edge diffraction.And the straight edge diffraction laser standing wave field was analyzed.The model of laser standing wave field was established under the straight edge diffraction disturbance,the chromium atoms three-dimensional trajectory and deposition characteristics in the straight edge diffraction laser standing wave field is simulated by using the Runge-Kutta method.Considering the influence of laser parameters,the chromium atoms trajectory and deposition characteristics in straight edge diffraction standing wave field were analyzed when the laser power and detuning amount were changed.This paper analyzes the Chromium atomic deposition grating structure in numerical from the FWHM(Full Width at Half Maximum)and the Contrast.The results show that,when the laser power and the detuning amount are 3.93 mW and 200 MHz respectively,the FWHM of atomic deposition grating is 6.04 nm and the Contrast is 0.863.And the best quality of atomic deposition grating can be acquired.This paper considered the straight edge diffraction phenomena caused by the deposition substrate in the laser standing wave field,simulated the chromium atoms three-dimensional trajectory and deposition characteristics,the simulation results were closer to the actual and it is of theoretical guidance to the experiment.