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A new study aims to identify the structure of polysilicon films prepared using low-pressure vapor deposition at different temperatures.

The quality of thermal oxides on n-type 4H-SiC epitaxial layers doped heavily with nitrogen has been studied. The layers were deposited through ion-implantation and annealed at various temperatures. The oxides suffer from intrinsic breakdown at electric fields of about 8 and 10 MV/cm. There was a reduction in the SiC-SiO2 barrier height for capacitors with higher doses of nitrogen doping. It has also been proven that it is better to anneal at 1700 degrees C than at 1450 degrees C.

Research was conducted to examine the atomistic modeling of high-concentration effects of impurity diffusion in silicon on a microscopic model level. The microscopic forces between dopant atoms and vacancies are taken into consideration in performing the simulation. Simulation results for the different microscopic approaches are utilized to give an evaluation of the validity of models for high-concentration diffusion based on percolation theory.

Research was conducted to investigate the atomistic analysis of the vacancy mechanism of impurity diffusion in silicon. Measurement was performed from the atomistic mechanism through accurately taking into consideration the effects of the microscopic forces between vacancies and dopants. Results indicate that the reduction of the activation energy of dopant diffusivity can be explained by a nonbinding interaction that enlarges the vacancy mobility in the neighborhood of the dopant.

A study of the transport matrix associated with dopants and vacancies for coupled diffusion revealed the vacancy gradient to cause variations in the dopant and vacancy direction depending on potential range. Atomic jump frequencies were used to compute dopant and vacancy transport coefficients when dopant and vacancy gradients existed. This model encompassed the interaction potential between the point defect and the dopant.

A simulation model was used to investigate step coverage for chemical vapor deposited silicon dioxide on structured wafer surfaces. The results showed that adsorption and desorption of the deposition precursor effectively indicated the mechanics of deposition and step coverage of low-pressure chemical vapor deposition films.

The effective work function instability in high-k MOS gate stacks, which has occurred after high temperature processing, is discussed. The [V.sub.fo] roll-of effect is described by a consistent phenomenological model.

The segregation and pile-up of arsenic atoms at the Si/Si[O.sub.2] interface is steady state is examined by a combination of gracing incidence x-ray fluorescence spectroscopy measurements. Results are compared with electron energy loss spectroscopy (EELS) and Z-contrast measurements and a model is proposed that has described the relation between the sheet concentration of segregated arsenic atoms and the concentration of substitutional atoms in the bulk.

The Pt contamination issues after standard front-end of line processing, and the potential impact of Pt on memory device performance, are discussed. Phosphorous-doped polysilicon is an effective getter layer that can inhibit Pt diffusion to the active region of the selected transistors.

The diffusivity of aluminium in a temperature range from 850 to 1290 degrees Centigrade is determined. The aluminium diffuses predominantly through self-interstitials as diffusion vehicles and diffusion enhancement under oxidizing conditions.

Studies the trivalent character of platinum in silicon. Third dominant platinum level; Use of deep level transient spectroscopy; Activation energy.