Characterisation of n-type γ-CuCl on Si for UV optoelectronic applications

Abstract

The use of co-evaporation of ZnCl 2 with CuCl in order to achieve n-type conductivity in CuCl is reported herein. Linear current-voltage (IV) characteristics in the range of ±4V have been measured using Cu-Au electrical contacts. Room temperature Hall effect measurements show some evidence of a mixed conduction mechanism. On average the samples exhibit n-type conductivity with a bulk electron carrier concentration n ~ 1 x 10 16 cm -3 and Hall mobility µ ~ 29 cm 2 v -1 s -1 for a CuCl sample doped with a nominal 3 mole % ZnCl 2 . By use of an in situ CaF 2 capping layer, transmission > 90% is achieved. At room temperature a strong Z 3 free excitonic emission occurs at ~385 nm using both photoluminescence and x-ray excited optical luminescence, indicating the high optical quality of the doped material.

UV emission on a Si substrate: Optical and structural properties of γ‐CuCl on Si grown using liquid phase epitaxy techniques

“…It can be clearly seen that the luminescence from the KCl-CuCl film is considerably (2-3 orders of magnitude) brighter than that of the GaN sample. It is also approximately an order of magnitude brighter then previously observed vacuum deposited CuCl samples studied with XEOL [19]. the β-CuCl to γ-CuCl phase transition point as well as below the known CuCl/Si reaction point.…”