AI Article Synopsis
- The study investigates how the long-range order of Se-Te films changes based on the type of silicon (Si) substrate used (p-type vs. n-type).
- The films grown on p-Si substrates show greater anisotropy and a clearer pattern compared to those on n-Si substrates under the same lighting conditions.
- The differences in film quality are attributed to the electrical effects due to varying interfacial junction energetics between the Se-Te films and the different Si substrates, which impact the growth dynamics at the interface.
Article Abstract
The long-range order of anisotropic phototropic Se-Te films grown electrochemically at room temperature under uniform-intensity, polarized, incoherent, near-IR illumination has been investigated using crystalline (111)-oriented Si substrates doped degenerately with either p- or n-type dopants. Fourier-transform (FT) analysis was performed on large-area images obtained with a scanning electron microscope, and peak shapes in the FT spectra were used to determine the pattern fidelity in the deposited Se-Te films. Under nominally identical illumination conditions, phototropic films grown on p-Si(111) exhibited a higher degree of anisotropy and a more well-defined pattern period than phototropic films grown on n-Si(111). Similar differences in the phototropic Se-Te deposit morphology and pattern fidelity on p-Si versus n-Si were observed when the deposition rate and current densities were controlled for by adjusting the deposition parameters and illumination conditions. The doping-related effects of the Si substrate on the pattern fidelity of the phototropic Se-Te deposits are ascribable to an electrical effect produced by the different interfacial junction energetics between Se-Te and p-Si versus n-Si that influences the dynamic behavior during phototropic growth at the Se-Te/Si interface.
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| http://dx.doi.org/10.1021/acs.nanolett.8b04891 | DOI Listing |
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