In-Situ Photoexcitation-Induced Suppression of Point Defect Generation in Ion Implanted Silicon

Conference · Mon Apr 05 04:00:00 EDT 1999

OSTI ID:6878

Cho, C R ^[1]; Rozgonyi, G A; Yarykin, N; Zuhr, R A

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1. ORNL

The formation of vacancy-related defects in n-type silicon has been studied immediately after implantation of He, Si, or Ge ions at 85 K using in-situ DLTS. A-center concentrations in He-implanted samples reach a mazimum immediately after implantation, whereas, with Si or Ge ion implanted samples they continuously increase during subsequent anneals. It is proposed that defect clusters, which emit vacancies during anneals, are generated in the collision cascades of Si or Ge ions. An illumination-induced suppression of A-center formation is seen immediately after implantation of He ions at 85 K. This effect is also observed with Si or Ge ions, but only after annealing. The suppression of vacancy complex formation via photoexcitation is believed to occur due to an enhanced recombination of defects during ion implantation, and results in reduced number of vacancies remaining in the defect clusters. In p-type silicon, a reduction in K-center formation and an enhanced migration of defects are concurrently observed in the illuminated sample implanted with Si ions. These observations are consistent with a model where the injection of excess carriers modifies the defect charge state and impacts their diffusion.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN
• Sponsoring Organization: USDOE Office of Science
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 6878
• Report Number(s): ORNL/CP-102823; KC 02 02 05 0; ON: DE00006878
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Excitation
Inhibition
Ion Implantation
Point Defects
Silicon