آنالیز میکروسکوپ تونلی روبشی STM و میکروسکوپ نیروی روبشی SFM

scanning tunneling microscope (STM) 

Scanning Force Microscopy (SFM)

آنالیز میکروسکوپ تونلی روبشی STM و میکروسکوپ نیروی روبشی  SFM

ABSTRACT

Scanning tunneling microscopy (STM) and its offspring, scanning force microscopy (SFM) , are real-space imaging techniques that can produce topographic images of a surface with atomic resolution in all three dimensions. Almost any solid surface can be studied with STM or SFM : insulators, semiconductors, and conductors, transparent as well as opaque materials. Surfaces can be studied in air, in liquid, or in ultrahigh vacuum, with fields of view from atoms to greater than 250*250um. With this flexibility in both the operating environment and types of samples that can be studied, STM/SFM is a powerful imaging system.

 

روش فیلترینگ غیرخطی برای حذف صدای ریزنگار HR(S)TEM

A nonlinear filtering algorithm for denoising HR(S)TEM micrographs

روش فیلترینگ غیرخطی برای حذف صدای ریزنگارهای HR(S)TEM

ABSTRACT

Noise reduction of micrographs is often an essential task in high resolution (scanning) transmission electron microscopy (HR(S)TEM) either for a higher visual quality or for a more accurate quantification. Since HR(S)TEM studies are often aimed at resolving periodic atomistic columns and their non-periodic deviation at defects, it is important to develop a noise reduction algorithm that can simultaneously handle both periodic and non-periodic features properly. In this work, a nonlinear filtering algorithm is developed based on widely used techniques of low-pass filter and Wiener filter, which can efficiently reduce noise without noticeable artifacts even in HR(S)TEM micrographs with contrast of variation of background and defects. The developed nonlinear filtering algorithm is particularly suitable for quantitative electron microscopy, and is also of great interest for beam sensitive samples, in situ analyses, and atomic resolution EFTEM.