Kim Tae-Hoon, Kang Min-Chul, Jung Ga-Bin, Kim Dong Soo, Yang Cheol-Woong
School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Korea.
Powder & Ceramics Division, Korea Institute of Materials Science, Changwon 51508, Korea.
Microsc Microanal. 2017 Oct;23(5):1055-1060. doi: 10.1017/S1431927617012557. Epub 2017 Sep 13.
The preparation of transmission electron microscopy (TEM) samples from powders is quite difficult and challenging. For powders with particles in the 1-5 μm size range, it is especially difficult to select an adequate sample preparation technique. Epoxy is commonly used to bind powder, but drawbacks, such as differential milling originating from unequal milling rates between the epoxy and powder, remain. We propose a new, simple method for preparing TEM samples. This method is especially useful for powders with particles in the 1-5 μm size range that are vulnerable to oxidation. The method uses solder as an embedding agent together with focused ion beam (FIB) milling. The powder was embedded in low-temperature solder using a conventional hot-mounting instrument. Subsequently, FIB was used to fabricate thin TEM samples via the lift-out technique. The solder proved to be more effective than epoxy in producing thin TEM samples with large areas. The problem of differential milling was mitigated, and the solder binder was more stable than epoxy under an electron beam. This methodology can be applied for preparing TEM samples from various powders that are either vulnerable to oxidation or composed of high atomic number elements.
从粉末制备透射电子显微镜（TEM）样品非常困难且具有挑战性。对于粒径在1 - 5μm范围内的粉末，选择合适的样品制备技术尤为困难。环氧树脂通常用于粘结粉末，但仍存在一些缺点，例如由于环氧树脂和粉末之间研磨速率不均导致的差异研磨。我们提出了一种新的、简单的TEM样品制备方法。该方法对于粒径在1 - 5μm范围内且易氧化的粉末特别有用。该方法使用焊料作为包埋剂并结合聚焦离子束（FIB）研磨。使用传统的热镶嵌仪将粉末嵌入低温焊料中。随后，通过取出技术使用FIB制造薄TEM样品。事实证明，在制备大面积薄TEM样品方面，焊料比环氧树脂更有效。差异研磨问题得到缓解，并且在电子束下焊料粘结剂比环氧树脂更稳定。这种方法可用于从各种易氧化或由高原子序数元素组成的粉末制备TEM样品。
