The excessive damage and high defect density generated during ionhyphen;beam etching of crystalline Si is characterized by Rutherford backscattering, photoluminescence, and transmission electron microscopy. In samples etched at room temperature, a highly damaged surface layer (dape;5 nm) with a large concentration of noble gas atoms is detected and analyzed using Rutherford backscattering in axial channeling geometry. Point defects due to the lowhyphen;energy noble gas ion implantation are produced within a depth of 100 nm and deeper, and are monitored by their characteristic photoluminescence. The intensity of the noblehyphen;gashyphen;defect photoluminescence is studied for different ionhyphen;beam energies (200ndash;2000 eV) and crystal orientations. A threshold to produce the defects can then be determined, leading to an estimate of the number of vacancies contained in the noble gas defect. Annealing of etched samples at 650thinsp;deg;C causes the formation of different new photoluminescent centers. Although little is known about the structure of these defects, it is observed that the defects effectively getter copper. Further annealing of the Arhyphen;etched samples at 1050thinsp;deg;C causes the formation of Ar bubbles with an average diameter of about 5 nm.
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