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Titanium silicide films formed by ion beam mixing with germanium were used to contact diodes with shallow p+n junctions. A generation mechanism located in the space charge layer was found to dominate the leakage current of the diodes. Further spectroscopy measurements revealed that ion beam mixing with heavy ions causes recoil implantation of titanium alloys into the silicon substrate. The leakage currents of Ti-silicide p+n junctions were also found to be related to the double donor Ti level found at Ev + .26 eV.

The influence of the deposition temperature during the reactive sputtering process on the microstructure of thin Ir and IrO[sub 2] films deposited on oxidized Si substrates was investigated and related to the oxygen barrier effectiveness. For this purpose differential thermal analysis combined with residual gas analysis by mass spectrometry was used for the investigation of the microstructural and chemical behavior of the as-sputtered IrO[sub 2] films upon heating. Moreover, in situ stress relaxation analyses up to 900 °C, in and ex situ x-ray diffraction measurements were done for various annealing conditions. The investigated polycrystalline IrO[sub 2] films exhibited a large compressive stress and a distorted lattice due to the sputter deposition process. It is demonstrated that a high deposition temperature involves a delayed relaxation of the IrO[sub 2] grains which is causing an extrinsic, enhanced defect controlled oxygen mobility for the annealing temperatures below the recrystallization. The well-known low intrinsic oxygen diffusivity was only found in those samples which show—in addition to the recovery process—a recrystallization at low temperatures and thus a formation and growth of a new generation of grains with a lattice spacing as in bulk IrO[sub 2]. Moreover, the oxygen diffusion in Ir films was investigated and the oxygen was found to penetrate the Ir films very quickly at elevated temperatures. The microstructure of the films was investigated by cross sectional transmission electron microscopy and it is shown that the cold-sputtered columnar IrO[sub 2] films protect the underlying layers from oxidation during a 700 deg;C high temperature oxygen anneal with an optimized Ir/IrO[sub 2] oxygen barrier stack. [ABSTRACT FROM AUTHOR]

A differential thermal analysis combined with residual gas analysis by mass spectrometry was conducted to investigate the influence of the deposition temperature, during the reactive sputtering process on the microstructure of thin Ir and IrO2 films deposited on oxidized Si substrates. The result reveals that a high deposition temperature involves a delayed relaxation of the IrO2 grains which is causing an extrinsic, enhanced defect controlled oxygen mobility for the annealing temperatures below the recrystallization.

The oxygen diffusion in reactively dc-sputtered IrO2 films is investigated by using the (super 18)O tracer diffusion method. It is shown that the extrinsic oxygen diffusion is strongly influenced by the film preparation conditions, which is important for the application of IrO2 films as an oxygen barrier in future memory device applications.

The effects of annealing in forming gas 5% hydrogen, 95% nitrogen; FGA) are studied on spin-coated SrBi[SUB2]Ta[SUB2]O[SUB9] SBT thin films. SBT films on a platinum bottom electrode are characterized with and without a platinum top electrode. Films are characterized by residual stress measurements, scanning electron microscopy (SEM), Auger electron spectroscopy (AES), high-temperature X-ray diffraction (HT-XRD) and secondary ion mass spectrometry (SIMS). To determine the degree of strain, lattice constants of Pt are measured by X-ray diffraction (XRD). (HT-XRD) of blanket SBT/Pt/Ti films in forming gas revealed that the bismuth-layered perovskite structure of SBT is stable up to approximately 500 °C. After formation of an intermediate phase between 550 °C and 700 °C, SBT changes its structure to an amorphous phase. SIMS analysis of Pt/SBT/Pt samples annealed in deuterated forming gas 5% D[SUB2], 95% N[SUB2] showed that hydrogen accumulates in the SBT layer and at the platinum interfaces next to the SBT. After FGA of blanket SBT films, tall platinum-bismuth whiskers are seen on the SBT surface. It is confirmed that these whiskers originate from the platinum bottom electrode and grow through the SBT layer. FGA of the entire Pt/SBT/Pt/Ti stack shows two different results. For the samples with a high-temperature annealing (HTA) step in oxygen after top electrode patterning, peeling of the top electrode is observed after FGA. For the samples without a HTA step, no peeling is observed after FGA. The residual stress at room temperature is measured for blanket platinum wafers deposited at different temperatures. It is found that an increase in tensile stress caused by the HTA step in oxygen is followed by a decrease in stress caused by the hydrogen in the forming gas. Without HTA, however, an increase of stress is observed after FGA. [ABSTRACT FROM AUTHOR]

SrBi[sub 2]Ta[sub 2]O[sub 9] thin films were prepared by metalorganic decomposition on Pt/Ti/SiO[sub 2]/Si substrates and subsequently crystallized at temperatures ranging from 600 to 700°C for 40 to 225 min. Data of the Aurivillius surface coverage taken from atomic force microscopy measurements were used to model the kinetics of isothermal phase transformation from the fluorite to the Aurivillius phase. A two-dimensional growth mechanism at a decreasing nucleation rate can be deduced. By evaluating the temperature dependence of the growth rates, an activation energy for phase transformation of 318 kJ/mol is determined. [ABSTRACT FROM AUTHOR]