Characterization of grain boundaries in CdTe polycrystalline films

Abstract

Abstract. CdTe polycrystalline films with the average size of grains within the range 10…360 m were grown on sapphire substrates by using the modified close-spaced sublimation technique. Transverse (across the film) and lateral (along the film's surface) conductivity as a function of bias voltage and temperature were measured using appropriate arrangement of contacts. The transverse conductivity exhibits ohmic behavior, whereas the lateral transport of carriers is dominated by potential barriers at the grain boundaries. The carrier concentration in the grains and the potential barrier height have been estimated. The inhomogeneous distribution of deep defects through the grains was found from the photoluminescence measurements.

Core and Shell Contributions to the Phonon Spectra of CdTe/CdS Quantum Dots

“…Properties of such NCs can be easily tuned by synthesis, leading to numerous promising properties [1][2][3]. In any of the perspective applications, the properties of the NC surface or the interface in case of core/shell NCs are determinant, primarily for their photoluminescence (PL) [3][4][5], as well as for charge and energy transfer phenomena [4][5][6][7][8]. In particular, an interplay of the shell thickness, effect of alloying (either targeted by the synthesis or occurring in an uncontrollable manner) at the core/shell interface, and the magnitude of residual strain in both core and shell is determinant for the NC properties, but hard to be measured [4,5,9,10].…”