Abstract
The ultra-thin nitrided oxide grown by microwave plasma afterglow oxidation at low temperature in the mixtures of N2O and O2 ambient has been investigated. By changing the N2O to O2 ratios in the mixtures, the optimal incorporation of nitrogen in the thin oxide can be controlled. All the results show that the ultra-thin oxide grown by this method had excellent quality and reliability comparable with the best thermally grown nitrided oxides at high temperature. Electron trap in silicon dioxide is a problem in the long term stability of metal-oxide-semiconductor field-effect transistors (MOSFETs) and an important degradation mechanism in electrically-alterable read-only-memories (EAROMs). Determination of the nature and distribution of oxide charge in MOS structures is important to an understanding of oxide charging phenomena. The variation of the bulk oxide charge build-up characteristics of ultra-thin oxide grown in different mixture of N2O:O2 after different Fowler-Nordheim stress conditions are investigated in this thesis. Determining the position of trapped charge in the insulator layer of a metal-oxide-semiconductor structure has been limited in the past by techniques that are sensitive to only one interface, such as the capacitance-voltage (C-V) technique in which only the product of the centroid and trapped charge density can be determined. In this thesis, we used a technique which is minimally perturbing and sensitive to both interfaces of an MOS structure by extending the photocurrent-voltage technique This technique allows rapid determination of the density of bulk trapped space charge and its centroid in insulator layer. The physical mechanism dominating the voltage dependence of photo-injected currents in SiO2 is the scattering of electrons in the region of the oxide between the injecting electrode and the image force porential maximum. Capacitance-V0ltage (C-V) technique is also help us to analyze the charge on the Si-oxide interface in oxides grown in various mixtures of N2O:O2. The high frequency C-V measurement and quasi-state C-V measurement were used to study the oxide charge in the oxide in the various samples. Secondary ion mass spectroscopy (SIMS) were employed to obtain the oxide structure and nitrogen profiles in the various samples.