Details

Autor(en) / Beteiligte

• Lu, G-Q

Titel

Pressure-Enhanced Crystallization Kinetics of Amorphous Silicon and Germanium

Erscheinungsjahr

1990

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The effects of hydrostatic pressure on the solid phase epitaxial growth (SPEG) reates of intrinsic Ge(100) and undoped and doped Si(100) into their respective self-implanted amorphous phases were measured. Samples are annealed in a high-temperature, high-pressure diamond anvil cell. Fluid Ar is used as the pressure transmission medium which ensures a clean and perfectly hydrostatic environment around the sample, and the external heating geometry employed in the cell provides a uniform temperature across the sample. The SPE growth rates are determined by in situ time-resolved visible (for Si) or infrared (for Ge) interferometry. It was found that pressure enhances the growth process in both Si and Ge. For Ge, an activation volume of --6.3 plus/minus 0.60 cm exp 3 /mole (--46% of Ge atomic volume) is measured in the temperature range 300-365 deg C and at pressures up to 5.2 GPa (52 kbar). For the growth process in undoped Si, at temperatures in the range of 520-550 deg C and pressures up to 5.0 GPa (50 kbar), an activation volume of --3.3 plus/minus 0.3 cm exp 3 /mole (--28% of Si atomic volume) was found. Dopant profiles of arsenic, boron, phosphorus, and compensating B and P are implanted at single energies into Si amorphized by self-implantation. The effect of pressure on SPE growth of these doped samples shows that the process in Si not only is independent of dopant concentration, but also does not depend on the dopant type. Implications of this work for the nature of the defects responsible for the crystal growth process in Si and Ge are discussed. It is concluded that only a few of the proposed defects, such as dangling bonds at the crystal/amorphous interface (Spaepen and Turnbull), kink sites at the interface (Williams and Elliman), and floating bonds in the bulk amorphous phase (Pantelides), could control the SPEG process. (DA9021806).--AA