Self-Catalyzed CdTe Wires

Abstract

CdTe wires have been fabricated via a catalyst free method using the industrially scalable physical vapor deposition technique close space sublimation. Wire growth was shown to be highly dependent on surface roughness and deposition pressure, with only low roughness surfaces being capable of producing wires. Growth of wires is highly (111) oriented and is inferred to occur via a vapor-solid-solid growth mechanism, wherein a CdTe seed particle acts to template the growth. Such seed particles are visible as wire caps and have been characterized via energy dispersive X-ray analysis to establish they are single phase CdTe, hence validating the self-catalysation route. Cathodoluminescence analysis demonstrates that CdTe wires exhibited a much lower level of recombination when compared to a planar CdTe film, which is highly beneficial for semiconductor applications.

An In-Depth Analysis of CdTe Thin-Film Deposition on Ultra-Thin Glass Substrates via Close-Spaced Sublimation (CSS)

“…The average grain size of the films deposited at 200 Torr is smaller (<1 µm) than the other samples (~2 to 5 µm). The smaller grain size of the film is mostly attributed to a reduction in the mean free path of molecules as pressure increases, as well as a decrease in nucleation and island formation number [42]. The reducing pattern of average thickness plotted in Figure 5b affirms the distorted nucleation of CdTe at high deposition pressure.…”

Arrayed CdTeMicrodots and Their Enhanced Photodetectivity via Piezo-Phototronic Effect

“…Due to its attractive bandgap and optical properties, CdTe in the nanostructures form is a potential candidate for the fabrication of a high-performance devices. Different morphologies of CdTe, such as nanoparticles, nanowires, nanorods, and nanotubes have been synthesized via a variety of methods including molecular beam epitaxy, chemical vapor deposition (CVD), physical vapor deposition, electrodeposition, closed spaced sublimation (CSS) method, and radio frequency(RF) magnetron sputtering [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. CdTe solar cells on ultrathin glass substrates, yielding a high efficiency of 16.4%, have also been reported by Mahabaduge et al [ 21 ].…”