Ion beam techniques are widely used in material science for the analysis and modification of materials. While ion beam techniques have their origin in the early 1900s with early experiments for their use taking place in the 1950s, modelling their effects also dates all the way back to the 1960s. Despite their longstanding history, the capabilities of modelling approaches have continued to improve in large part due to increasing computing power.

Despite the capabilities of modelling using modern computers, simulations are rarely used to their fullest extent to aid experimental work. The application of software can be incredibly useful to narrow down parameters and focus an experimental investigation. This thesis focuses on a variety of simulation techniques on a diverse array of projects, both alongside experimental work and purely theoretical.

Chapter 5 describes the simulation of an array of XPS depth profiles for monoatomic irradiation of metal oxides. XPS depth profiling is a key technique in many industry processes and its use on non-organic targets such as semiconductors and polymers is common. The depth profiling utilises an ion beam to sputter the target and as such can cause various matrix effects. The application of dynamic Monte Carlo simulation codes can help in predicting the effects of different beam conditions on experimentally measured bias.

Chapter 4 contains an investigation on the simulation on the XPS depth profiling of GaAs with Ar clusters. Gas cluster ion beams (GCIBs) are commonly used in the sputtering of compounds where the detection of intact molecules is important. It is hoped that in the sputtering of a common semiconductor material of GaAs that damage to the crystalline structure and atomic mixing caused by the ion beam would be minimised. The application of molecular dynamics (MD) has been used to predict the effect that the beam conditions have on preferential sputtering.

Chapter 6 details the simulation of the ammorphisation of a Si thin film. Amorphous Si is commonly used in passivation layers in photovoltaics. As such, understanding the amorphisation of a thin film of Si with a Ga focused ion beam (FIB) is key. The application of a MD model allows for the analysis of the amorphisation and the comparison to a novel application of convergent beam electron diffraction (CBED) analysed by peak signal to noise ratio (PSNR).

Chapter 7 is a study on the simulation of ion beam augmentation of Ag Nanoparticles. Ag nanostructures, particularly nanoparticles (NP) have a lot of applications in optoelectronic and medical purposes. This is due to their tuneable optical properties and their antimicrobial effect. The augmentation of their sizes and shapes is important in tailoring them for their uses. Ag NPs embedded in Si₃N₄ can be augmented by irradiation with a 200 keV Ne beam and analysed by MEIS. This has been compared to results from the 3D Monte Carlo code TRI3DYN to give information on how the beam conditions effect the NP.

Chapter 8 is a study on the phenomenon of “void defocussing” in nanoporous materials. Nanoporous materials are known to be radiation hard as the interfaces within them act as perfect defect sinks. The voids between nanostructures also act to defocus the beam. In order to show this effect, the modelling codes transport of ions in matter (TRIM), TRI3DYN, and a modified version of TRIM were used. These have demonstrated the effect of the void on the spread of radiation and the effect of a large fluence of radiation on the void. Empirical data from an experiment is necessary to advance the model and improve results.

These projects, while not intrinsically linked, all demonstrate the broad applicability of these techniques and how they can be applied. Chapter 9 draws conclusions and makes suggestions where additional work can be carried out for each of the aforementioned projects.