Dae‐Hong Ko

Phosphorus has low solubility in silicon, but nonequilibrium incorporation of phosphorus exhibits unusual high strain and low contact resistance for advanced Si-based metal-oxide-semiconductor field-effect transistors. Despite recent technological breakthroughs, the origin of tensile strain and electrical deactivation in P-doped Si films is not yet fully understood. Here, by using a combination of experiments and first-principles calculations, we investigate the effect of nonequilibrium phosphor

We have investigated the amorphous phase formation and initial crystalline reactions at Pt/GaAs interfaces via high-resolution transmission electron microscopy (HRTEM) and in situ HRTEM. A 3-nm-thick amorphous intermixed layer consisting of three elements, platinum, gallium, and arsenic formed at the Pt/GaAs interface during the deposition of a 500-Å-thick Pt film. The interlayer grew in a planar fashion in an amorphous state upon low temperature (e.g., 200 °C) annealing by a solid-state amorphi

In situ phosphorus‐doped epitaxial silicon films have attracted significant attention as source and drain materials because low specific contact resistivities have been achieved on such films by increasing the active carrier concentration using millisecond laser annealing. However, the active phosphorus concentration that can be achieved using millisecond laser annealing is much less than the incorporated concentration. To increase the activation efficiency, nanosecond laser annealing with a dwe

Conventional Si or SiGe epitaxy via chemical vapor deposition is performed at high temperatures with a large amount of hydrogen gas using silane (SiH4) or dichlorosilane (SiCl2H2) precursors. These conventional precursors show low growth rates at low temperatures, particularly below 500 °C although a low thermal budget becomes more important for modern fabrication techniques. High-order silane precursors, such as disilane, trisilane, and tetrasilane, are candidates for low-temperature epitaxy du

The presence of a thin amorphous intermixed layer at the platinum-GaAs interface in as-deposited Pt/GaAs and Si/Pt/GaAs samples has been investigated via high-resolution electron microscopy, microdiffraction, and energy dispersive spectroscopy. The intermixed layer forms below the native oxide of the GaAs substrate and consists of three elements, platinum, gallium, and arsenic. We suggest that this layer forms during the deposition process of the platinum.

We investigated the lattice vibration and strain states in highly P-doped epitaxial Si films using Raman scattering and X-ray diffraction (XRD) measurements.