Determination of Nitrogen Concentration in Dilute GaNAs by STEM HAADF Z-Contrast Imaging
نویسندگان
چکیده
منابع مشابه
Polarity determination in ZnSe nanowires by HAADF STEM
High angle annular dark field scanning transmission electron microscopy is used to analyze the polarity of ZnSe nanowires grown, by molecular beam epitaxy, on GaAs substrates. The experimental results are compared to simulated images in order to verify possible experimental artefacts. In this work we show that for this type of nano-objects, a residual tilt of the specimen below 15 mrad, away fr...
متن کاملMeasuring composition in InGaN from HAADF-STEM images and studying the temperature dependence of Z-contrast
In this contribution, the indium concentration profile of an InxGa1-xN/GaN five-fold multi quantum well structure is measured from high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) images. The results are compared with an atom probe tomography study. Indium concentrations in the range of 26 at.% to 33 at.% are measured in the centre of the quantum wells. An ad...
متن کاملUnexpected Bismuth Concentration Profiles in MOVPE GaAs1-xBix Films Revealed by HAADF STEM Imaging
Recent interest in the growth of GaAs1-xBix semiconductor alloys with controlled Bi concentration has been stimulated by the sensitivity of the bandgap energy and valence band structure to Bi concentration, x. These sensitivities offer the possibility to engineer both the band gap and band offsets at junctions to improve the performance of devices. Realization of this potential, however, requir...
متن کاملAnalytical determination of the chemical exchange saturation transfer (CEST) contrast in molecular magnetic resonance imaging
Magnetic resonance based on molecular imaging allows tracing contrast agents thereby facilitating early diagnosis of diseases in a non-invasive fashion that enhances the soft tissue with high spatial resolution. Recently, the exchange of protons between the contrast agent and water, known as the chemical exchange saturation transfer (CEST) effect, has been measured by applying a suitable pulse ...
متن کاملStructure Determination Through Z-Contrast Microscopy
The technique of Z-contrast scanning transmission electron microscopy (STEM) provides an incoherent image of crystals at atomic resolution. There are no phases in an incoherent image, therefore, no phase problem for structure determination. Location of atom column positions in an image is greatly simplified. In addition, the resolution is a factor of two higher than in a coherent image, the inf...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Physics: Conference Series
سال: 2011
ISSN: 1742-6596
DOI: 10.1088/1742-6596/326/1/012033