Thin film diamond devices as photon and ionising radiation detectors

The emergence over the past decade of new techniques for the synthesis of high quality diamond films having a range of unique properties which include a wide bandgap, high carrier mobilities, high electric field breakdown strength and radiation hardness, has created the opportunity to exploit this material in the fabrication of microelectronic sensors. New insight is offered into the electronic and electro-optic properties of thin polycrystalline diamond films in respect to the processing and performance of devices for the detection of deep ultraviolet light and ionising radiation. The known properties of natural and synthetic diamond are reviewed and evaluated in the context of previous studies which have sought to develop diamond electronic devices. A design philosophy and experimental methods are identified by which high performance ultraviolet photodetector structures may be fabricated to overcome the limitations of contemporary films, and prototype devices are presented and evaluated. Vacuum and gas ambient processes are proposed and undertaken which act to optimise specific aspects of detector performance such as speed or sensitivity and the mechanisms by which such processes operate are discussed. Further engineering of the optical detection capabilities of thin film diamond devices is explored with the aim of effecting modifications to the spectral profile of the detector's sensitivity. The detection of alpha particles is undertaken and evaluated with a view to optimisation and the hardness of the detectors to gamma radiation is explored. Finally, in view of the current advanced state of commercial exploitation of the devices described, a brief review is undertaken to identify the realistic market impact of diamond electronic devices