Combining Electron and Optical Spectroscopy to Study the Diamond Surface for NV Centre Applications

Abstract

This thesis presents a study of chemical and electronic properties of the (100) oxygen terminated surface of diamond as a basis for quantum applications revolving around near surface nitrogen-vacancy centres. A combination of X-ray Photoelectron Spectroscopy (XPS) Ultraviolet Photoelectron Spectroscopy (UPS), Real-time Electron Energy Spectroscopy (REES) and Near-Ambient Pressure XPS (NAP-XPS) have been implemented. A computational model has also been developed to describe the surface photovoltage generated during these measurements and its dependency on temperature. A (001) moderately boron doped diamond was oxygen terminated by two methods and monitored in real time during a series of annealing cycles up to 1000oC. The desorption mechanisms, chemical species stoichiometry and the electronic band structures will be present herein. During this work a work function of 2.42 eV from a plasma treated surface was found, the highest reported for an oxygen terminated diamond surface. In conjunction, the design, construction, calibration and initial measurement of the OptiXS instrument will be presented. Whilst the use of optical and electron spectroscopy is commonplace in materials science, they are rarely, if ever performed together. The OptiXS (Optical and X-ray Spectroscopy) instrument has been developed to provide the ability to perform these techniques simultaneously and insitu, opening possible avenues for real-time, parallel optical and electron spectroscopic studies during sample processing techniques, such as thin film deposition, heating or cooling cycles or ion bombardment. Within this thesis the manipulator design process, calibration experiments, and initial attempts at nitrogen implantation will be given. All XPS and REES taken in this work has been fitted using the newly developed Materials Characterisation Suite, an analysis package which currently specialises in photoemission core level fitting and REES fit propagation. The background theory, analysis procedures, and user interfaces will also be presented in this work.

Date of Award	2021
Original language	English
Awarding Institution	Aberystwyth University
Supervisor	Andrew Evans (Supervisor) & Huw Morgan (Supervisor)