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We present details of the deposition of transparent and earth-abundant p-type CuBr films with high hole conductivity and the fabrication and characterization of a prototype solar cell based on p-CuBr/n-Si

Copper (I) chloride is naturally a direct band gap, zincblende and p-type semiconductor material with much potential in linear and non-linear optical applications owing to its large free excitonic binding energy. In order to fabricate an efficient electrically pumped emitter, a combination of both p-type and n-type semiconductor materials will be required. In this study, we report on the growth of n-type γ-CuCl with improved carrier concentration by pulsed dc magnetron sputtering of CuCl/Zn target. An improvement of carrier concentration up to an order of ~ 9.8x10 18 cm-3 , which is much higher than the previously reported (~ 10 16 cm-3), has been achieved. An enhancement in crystallinity of CuCl along the (111) orientation and its consistency with the morphological studies have also been investigated as an effect of doping. Influence of Zn wt % in the sputtering target on the Hall mobility and resistivity of the doped films is explored. The strong ultraviolet emission of doped films is confirmed using room temperature and low temperature photoluminescence studies.

Cuprous halides are among the most studied inorganic materials for excitonic related linear/non-linear optical processes due to their large excitonic binding energies (∼190 and 108 meV for CuCl and CuBr, respectively). In recent years, we have studied CuCl thin films deposited by vacuum evaporation and sputtering techniques on a variety of substrates. We now report on the extension of this research to the deposition of CuCl nanocrystals on flexible substrates via a spin-on technology. In this study, we present the synthesis, deposition and characterization of CuCl nanocrystals embedded in organic polysilsesquioxane (PSSQ) films on a variety of substrates via the spin coating method. The nanocrystals were synthesized by a complexation–reduction–precipitation mechanism reaction of CuCl2 · 2H2O, alpha D-glucose and de-ionized (DI) water with a PSSQ based solution as the host matrix material. The deposited films were heated at 120 °C for durations between 1 and 24 h in vacuo. The room temperature UV–Vis absorption spectra for all hybrid films, except the as-deposited film, showed both Z1,2 and Z3 excitonic absorption features. Room temperature photoluminescence measurements of all heated films reveal very intense Z3 excitonic emission at 3.221 eV. Room temperature x-ray diffraction (XRD) of the as-deposited films gave no evidence of the crystallization of CuCl. However, after heating the films, XRD confirmed the preferential growth of CuCl nanocrystals whose average size is ≈25–45 nm in the ⟨1 1 1⟩ orientation. The CuCl hybrid films showed bright electroluminescent emission at 384 nm when subjected to an ac voltage of about 100 V peak to peak.

Optoelectronic technology frequently demands optically transparent materials. In this paper we present an overview of the development of ultrathin chromium films of above 80% optical transparency and 10 2 -10 3 mV cm resistivity using bipolar pulsed dc magnetron sputtering. The surface morphology and film resistivity are investigated using atomic force microscopy (AFM) and four point probe, respectively. The variation of the electrical properties of the film with thickness, pulse duty cycle and target power are examined. An optimal experimental condition is suggested for developing transparent metal contacts, which can be used for the realisation of optoelectronic devices including organic light-emitting diodes on flexible, low cost polymeric substrates. This process does not require high temperature and post-deposition annealing unlike other transparent conducting oxides.