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Chinese Physics B

Simulation research on surface growth process of positive and negative frequency detuning chromium atom lithographic gratings

Zhi-Jun 志珺 Yin 尹, Zhao-Hui 朝辉 Tang 唐, Wen 文 Tan 谭, Guang-Xu 光旭 Xiao 肖, Yu-Lin 玉林 Yao 姚, Dong-Bai 栋柏 Xue 薛, Zhen-Jie 振杰 Gu 顾, Li-Hua 李华 Lei 雷, Xiong Dun, Xiao 晓 Deng 邓, Xin-Bin 鑫彬 Cheng 程, Tong-Bao 同保 Li 李

Published Jul 21, 2023• 1 citation

Abstract

Chromium atom photolithography gratings are a promising technology for the development of nanoscale length standard substances due to their high accuracy, uniformity, and consistency. However, the inherent difference between the interaction of positive and negative frequency detuning standing wave field and the atoms can cause a difference in the adjacent peak-to-valley heights of the grating in positive and negative frequency detuning chromium atom lithography, which greatly reduces its accuracy. In this study, we performed a controlled variable growth simulation using the semi-classical theoretical model and Monte Carlo method with trajectory tracking and ballistic deposition methods to investigate the influence of key experimental parameters on the surface growth process of positive and negative frequency detuning atomic lithography gratings. We established a theoretical model based on simulation results and summarized empirical equations to guide the selection of experimental parameters. Our simulations achieved uniform positive and negative frequency detuning atomic lithography gratings with a period of 1/4 of the wavelength corresponding to the atomic transition frequency, and adjacent peak-to-valley heights differing by no more than 2 nm, providing an important theoretical reference for the controllable fabrication of these gratings.

DOI: 10.1088/1674-1056/ace95b

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