Selected area channeling pattern, defect etch and lifetime study of silicon implanted with oxygen

Electron channeling pattern analysis and etch pit counting have been used to study defects in SIMOX (separation by implantation of oxygen) materials. Data have also been obtained on photoconductive lifetime, which is an indirect measure of defect density. The samples were implanted with oxygen at 150 keV to a dose of 1.7×10¹⁸ cm^-2 at temperatures of 505 to 535°C. They were all annealed at 1250°C in N₂+1%O₂ and etched using the Wright etch formulation. The diameters of the etch pits ranged from 50 to 100 nm. The lifetimes in the microsecond range were measured using pulsed 20-ns excitation at 308 nm from an Xe-Cl excimer laser. A linear relation is observed between with width of the lines in the electron channeling pattern and the log of the dislocation density, as expected from diffraction density, as expected from diffraction theory