Abstract
Flat panel displays based on electron field emission can provide the benefits of the high resolution of a cathode ray tube display while possessing the portability of a liquid crystal display. To date, the problem with a field emission flat panel display based on silicon is that it usually involves complex photolithography processing, making it too complex and expensive to be commercially viable. In this thesis, the emphasis of the research is to fabricate a three terminal silicon device for flat panel display based on field emission technology without using photolithography processes. Laser crystallised amorphous silicon is chosen for our material which creates a rough silicon surface whose roughness gives rise to field enhancement. Furthermore, this process is widely used in the display industry to fabricate silicon based display driver thin film transistors, which can be readily incorporated. It is important to understand the electron field emission mechanism from the laser crystallised amorphous silicon and to find optimum conditions for emission. In the course of our research, we established a regime for super sequential lateral growth or a hybrid sequential lateral solidification and super lateral growth in Nd:YAG crystallisation of amorphous silicon. Excimer laser crystallised amorphous silicon under optimum conditions gives emission currents of the order of 10-5A (current densities ~ 0.04 A/cm2) at threshold fields less than 15 V/mum in a diode configuration, without the need for a forming process. Through experiments, we concluded that the field emission mechanism from these samples is not controlled purely by surface phenomena, contrary to what was suggested by the Fowler Nordheim theory. Instead, it is the diffusion of the underlay metals into the silicon that create clusters of silicide that allow the electrons to become "hot" while travelling between the clusters. Lastly, a novel process illustrating that a three-terminal device based on laser crystallised amorphous silicon can be fabricated without the need for photolithography. However, the field emission data showed that some fine-tuning of the process is still required.