Growth of >100 μm thick diamond layer adherent on aluminium nitride is presented in this work. While thick films failed to adhere on untreated AlN films, hydrogen/nitrogen plasma treated AlN films retained the thick diamond layers. Clear differences in zeta potential measurement confirms the surface modification due to hydrogen/nitrogen plasma treatment. Areal Raman maps showed an increase in non-diamond carbon in the initial layers of diamond grown on pre-treated AlN. The presence of non-diamond carbon has minimal effect on the interface between diamond and AlN. The surfaces studied with x-ray photoelectron spectroscopy (XPS) revealed a clear distinction between pre-treated and untreated samples. The surface aluminium goes from nitrogen rich environment to an oxygen rich environment after pre-treatment. Cross section transmission electron microscopy shows a clean interface between diamond and AlN. Thermal barrier resistance between diamond and AlN was found to be in the range of 16 m2K/GW which is a large improvement on the current state-of-the-art.
@article{arxiv.1907.02481,
title = {Thick adherent diamond films on AlN with low thermal barrier resistance},
author = {Soumen Mandal and Jerome Cuenca and Fabien Massabuau and Chao Yuan and Henry Bland and James W. Pomeroy and David Wallis and Tim Batten and David Morgan and Rachel Oliver and Martin Kuball and Oliver A. Williams},
journal= {arXiv preprint arXiv:1907.02481},
year = {2019}
}