4,218 publications from this institution
Shallower carrier concentration profiles in 50 keV P+-implanted Si(100) after annealing at 1000-degrees-C for 1 h have been observed when a buried amorphous layer was formed by an additional irradiation of 1.0 MeV Si+ ions prior to annealing (i.e., ion beam defect engineering process). The secondary defects formed in the MeV Si+ damaged region act as gettering sites for the collection of interstitials from the shallower depths which are responsible for the transient diffusion of P, and therefore the transient diffusion of P is reduced and the carrier concentration profiles become shallower.
Abstract For third generation semiconductors, for example, wurtzite ZnO and GaN, a piezopotential will be induced in these non‐centrosymmetric structures through applying a stationery deformation. The synchronous occupancy of semiconductor engineering, piezoelectric property, and optical excitation processes in these materials brings about outstanding device performances, such as promoting carrier creation, transfer, separation, or suppressing carrier recombination. Enormous research interests have been sparked in this emerging field known as the piezo‐phototronic effect. This manuscript reviews the fundamental research progress in enhanced photovoltaic efficiency by this effect, which not only provides a comprehensive coverage of the theoretical and experimental works illustrating the basic physics for understanding the enhanced solar cells when an external mechanical strain is applied, but also gives new insight into designing high‐performance solar cells.
Interfaces between a liquid and a solid (L-S) are the most important surface science in chemistry, catalysis, energy, and even biology. Formation of an electric double layer (EDL) at the L-S interface has been attributed due to the adsorption of a layer of ions at the solid surface, which causes the ions in the liquid to redistribute. Although the existence of a layer of charges on a solid surface is always assumed, the origin of the charges is not extensively explored. Recent studies of contact electrification (CE) between a liquid and a solid suggest that electron transfer plays a dominant role at the initial stage for forming the charge layer at the L-S interface. Here, we review the recent works about electron transfer in liquid-solid CE, including scenerios such as liquid-insulator, liquid-semiconductor, and liquid-metal. Formation of the EDL is revisited considering the existence of electron transfer at the L-S interface. Furthermore, the triboelectric nanogenerator (TENG) technique based on the liquid-solid CE is introduced, which can be used not only for harvesting mechanical energy from a liquid but also as a probe for probing the charge transfer at liquid-solid interfaces.
The electrochemical method of synthesis of gold nanorods in micelles gives substrate solutions that upon spotting and heating on a transmission electron microscope (TEM) substrate result in the nucleation and growth of small gold nanoclusters of narrow size distribution. The size of the nanoclusters, and not their numbers, is found to increased with increasing final temperature to which the substrate is heated. The data are fitted to a mechanism, based on Ostwald ripening in which atomic gold diffusion followed by nucleation on nucleating sites leads to the formation of these small clusters.
Numerous inelastic scattering processes are involved in electron scattering. The mean-free-path length of inelastic scattering is about 50–300 nm for most materials, thus more than 50% of the electrons will be inelastically scattered if the specimen thickness is close to the mean-free-path length. Inelastic scattering not only affects the quality of REM images and RHEED patterns but also makes data quantification much more complex and inaccurate. In this chapter, we first outline the inelastic scattering processes in electron diffraction. Then phonon (or thermal diffuse) scattering will be discussed in detail. The other inelastic scattering processes will be described in Chapters 10 and 11.
