Yuan Pengyu, Wu Jason Y, Ogletree D Frank, Urban Jeffrey J, Dames Chris, Ma Yanbao
Department of Mechanical Engineering, University of California, Berkeley, Berkeley, California 94720, United States.
The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
Nano Lett. 2020 May 13;20(5):3019-3029. doi: 10.1021/acs.nanolett.9b04940. Epub 2020 Apr 21.
The electron beam (e-beam) in the scanning electron microscopy (SEM) provides an appealing mobile heating source for thermal metrology with spatial resolution of ∼1 nm, but the lack of systematic quantification of the e-beam heating power limits such application development. Here, we systemically study e-beam heating in LPCVD silicon nitride (SiN) thin-films with thickness ranging from 200 to 500 nm from both experiments and complementary Monte Carlo simulations using the CASINO software package. There is good agreement about the thickness-dependent e-beam energy absorption of thin-film between modeling predictions and experiments. Using the absorption results, we then demonstrate adapting the e-beam as a quantitative heating source by measuring the thickness-dependent thermal conductivity of SiN thin-films, with the results validated to within 7% by a separate Joule heating experiment. The results described here will open a new avenue for using SEM e-beams as a mobile heating source for advanced nanoscale thermal metrology development.
扫描电子显微镜(SEM)中的电子束为热计量提供了一种具有吸引力的移动加热源,其空间分辨率约为1 nm,但电子束加热功率缺乏系统的量化限制了此类应用的开发。在此,我们通过实验以及使用CASINO软件包进行的补充蒙特卡罗模拟,系统地研究了厚度在200至500 nm范围内的LPCVD氮化硅(SiN)薄膜中的电子束加热情况。建模预测与实验结果在薄膜电子束能量吸收随厚度变化方面具有良好的一致性。利用吸收结果,我们随后通过测量SiN薄膜随厚度变化的热导率,证明了将电子束用作定量加热源,通过单独的焦耳加热实验验证,结果的误差在7%以内。本文所述结果将为利用扫描电子显微镜电子束作为移动加热源推动先进纳米级热计量学发展开辟一条新途径。