A study was made of the annealing behavior of extended defects in material which had been subjected to various Ge+ pre-amorphization and BF2+ implantation treatments. The extended defects which were formed were near to the specimen surface when the Ge+ implantation energy and dose were low. During annealing, the end-of-range loops enlarged and then moved out of the specimen. High-energy/low-dose Ge+ implantation generated a damaged layer which initially transformed into a wide zone that contained dislocation loops and rod-like defects. As annealing continued, the width of the defective zone gradually shrank, so that most of the extended defects could be annihilated by defect rejection/recombination processes. In addition to previously investigated defects, hair-pin dislocations were seen in high-energy/high-dose Ge+-implanted specimens. In such specimens, rod-like defects and hair-pin dislocations could be removed by annealing. Meanwhile, the end-of-range loops became relatively inert; so that their removal would require high temperatures and/or long annealing times. Microwave plasma surface treatments were also carried out in order to form a nitride layer on the specimen surfaces, since experimental results indicated that, as well as effectively reducing the size of end-of-range loops, surface nitrides might serve as vacancy sources which injected vacancies that annihilated interstitials that were bounded by dislocation loops. The reduction in defect size was marked when a bias voltage was added to the plasma process.

Defects in Ge+-Preamorphized Silicon P.S.Chen, T.E.Hsieh, Y.C.Hwang, C.H.Chu: Journal of Applied Physics, 1999, 86[10], 5399-406