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-Ga2O3 is a metastable phase of Ga2O3 of interest for wide bandgap engineering since it is isostructural with -In2O3 and -Al2O3. -Ga2O3 is generally synthesised under high pressure (several GPa) or relatively high temperature (~500 o C). In this study, we report the growth of -Ga2O3 by low temperature atomic layer deposition (ALD) on sapphire substrate. The film was grown at a rate of 0.48 Å/cycle, and predominantly consists of -Ga2O3 in the form of (0001)-oriented columns originating from the interface with the substrate. Some inclusions were also present, typically at the tips of the -phase columns and most likely comprising -Ga2O3. The remainder of the Ga2O3 filmi.e. nearer the surface and between the -Ga2O3 columns, was amorphous. The film was found to be highly resistive, as is expected for undoped material. This study demonstrates that -Ga2O3 films can be grown by low temperature ALD and suggests the possibility of a new range of ultraviolet optoelectronic and power devices grown by ALD. The study also shows that scanning electron diffraction is a powerful technique to identify the different polymorphs of Ga2O3 present in multiphase samples.

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A sensitive study of the decay of the deformation-aligned # = 14, 4-/is isomer in 174 Hf has revealed a multitude of A>forbidden branches to the ground-state rotational band and other low-A^ bands, in competition with the known decays to high-A' bands. The isomeric transitions have consistently low hindrance factors. These anomalous findings in an axially symmetric deformed nucleus severely test our understanding of the AT-selection rule. The isomeric decay to an 7 = 12 rotation-aligned state, and its mixing with the /"12 yrast state, provide a partial explanation.