Wolff Annalena, Klingner Nico, Thompson William, Zhou Yinghong, Lin Jinying, Xiao Yin
Kavli Nanoscience Institute, California Institute of Technology (Caltech), Pasadena CA91125, USA.
Central Analytical Research Facility, Institute for Future Environments, Queensland University of Technology (QUT), Brisbane QLD 4000, Australia.
Beilstein J Nanotechnol. 2024 Sep 27;15:1197-1207. doi: 10.3762/bjnano.15.97. eCollection 2024.
Ion beam-induced heat damage in thermally low conductive specimens such as biological samples is gaining increased interest within the scientific community. This is partly due to the increased use of FIB-SEMs in biology as well as the development of complex materials, such as polymers, which need to be analyzed. The work presented here looks at the physics behind the ion beam-sample interactions and the effect of the incident ion energy (set by the acceleration voltage) on inducing increases in sample temperature and potential heat damage in thermally low conductive materials such as polymers and biological samples. The ion beam-induced heat for different ion beam currents at low acceleration voltages is calculated using Fourier's law of heat transfer, finite element simulations, and numerical modelling results and compared to experiments. The results indicate that with lower accelerator voltages, higher ion beam currents in the nanoampere range can be used to pattern or image soft material and non-resin-embedded biological samples with increased milling speed but reduced heat damage.
离子束对热导率低的样品（如生物样品）造成的热损伤在科学界越来越受到关注。部分原因是聚焦离子束扫描电子显微镜（FIB-SEM）在生物学中的使用增加，以及需要分析的复杂材料（如聚合物）的发展。本文介绍的工作着眼于离子束与样品相互作用背后的物理原理，以及入射离子能量（由加速电压设定）对热导率低的材料（如聚合物和生物样品）中样品温度升高和潜在热损伤的影响。利用傅里叶传热定律、有限元模拟和数值模拟结果计算了低加速电压下不同离子束电流产生的离子束热，并与实验结果进行了比较。结果表明，在较低的加速电压下，纳安范围内的较高离子束电流可用于对软材料和非树脂包埋的生物样品进行图案化或成像，提高铣削速度但减少热损伤。
