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POINT DEFECT DETECTOR STUDIES OF Ge+ IMPLANTED SILICON UPON OXIDATION H. L. Meng, S. Prussin* and K. S. Jones Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611 *TRW Inc., Electronics Group, Redondo Beach, CA 90278 ABSTRACT Previous results [1] have shown that type II (end-of-range) dislocation loops can be used as point defect detectors and are efficient in measuring oxidation induced point defects. This study investigates the interaction between oxidation-induced point defects and dislocation loops when Ge+ implantation was used to form the type II dislocation loops. The type 1I dislocation loops were introduced via Ge+ implants into Si wafers at 100 keV to at doses ranging from 2x1015 to lxl06/cm 2. The subsequent furnace annealing at 900 °C was done for times between 30 min and 4 hr in either a dry oxygen or nitrogen ambient. The change in atom concentration bound by dislocation loops as a result of oxidation was measured by plan-view transmission electron microscopy (PTEM). The results show that the oxidation rate for Ge+ implanted Si is similar to Si+ implanted Si. Upon oxidation a decrease in the interstitial injection was observed for the Ge+ implanted samples relative to the Si+ implanted samples. With increasing Ge+ dose the trapped atom concentration bound by the loops actually decreases upon oxidation relative to the inert ambient implying oxidation of Ge+ implanted silicon can result itl either vacancy injection or the formation of an interstitial sink. INTRODUCTION Thermal oxidation of silicon is one of the most important processes for integrated circuit fabrication. It is well known that oxidation is responsible for the so called oxidation enhanced diffusion (OED) for species that diffuse interstitially and the growth of oxidation-induced stacking faults (OSF's) 12-81. This is attributed to excess Si interstitial generation during the oxidation process. OSF's have been identified as extrinsic defects, bound by Frank partial dislocations [9-101. Previously, extended defects studies of oxidation kinetics have been inferred mainly from the growth/shrinkage of stacking fault during oxidation. However, the size of OSF (-10 l.tm) and their density (5 106/cm 2) are not ideal for lower temperature point defect studies. In the previous paper [1], we reported using Si+ implantation to form type II dislocation loops [11 ] and investigated the interaction between the oxidation-induced point defects and type II dislocation loops. It was shown that because type II dislocation loops are much smaller (-0.02 p.m diameter) and greater in density (> 101°/cm 2 ) they provide a much more sensitive point defect detector. Recently 112-191 , it was reported that oxidation of Si is affected by the presence of Ge. The segregation of impurities at a oxide interface in Si plays an important role here. For dopants (or impurities) which have low solubility in Si0 2 , such as Ge, will be rejected by the oxide during growth and call pile up at the oxide/Si interface if the diffusion rate i