AMORPHIZATION OF SAPPHIRE DURING ION-BEAM MIXING

[摘要] Earlier studies indicated that implantation of zirconium into sapphire at room temperature produced an amorphous layer at a critical composition of approximately 6.5% (cation). Further insight into the amorphization of sapphire has been provided by ion beam mixing studies. Bi-layer couples of approximately 80 nm thick polycrystalline ZrO2 films deposited on the (0001) face of alpha-Al2O3 single crystals were irradiated to 4 x 10(16) ions/cm2 with Kr (475 keV, 20-degrees-C) or Cr (340 keV, 20-degrees-C or approximately 900-degrees-C). Transmission electron microscopy showed the unirradiated couples to have sharp, planar interfaces between the films and substrates. Recoil mixing by both ion species gave Zr concentrations greater than 10% (cation) to depths of 10-20 nm. An amorphous layer containing Zr was present at the interface for samples irradiated at room temperature. The sample mixed at the elevated temperature contained a sharp interface similar to the as-deposited sample. The present results suggest that both irradiation-produced damage (defects) and certain chemical species are required to amorphize sapphire.

[发布日期] 1994-06-01

[效力级别]  Proceedings Paper