Defects properties in plastically deformed silicon studied by positron lifetime measurements

✍ Scribed by Z. Wang; H.S. Leipner; R. Krause-Rehberg; V. Bodarenko; H. Gu

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 156 KB
• Volume: 66
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/s0167-9317(02)00942-5

✦ Synopsis

Positron lifetime spectra have been measured in float-zone silicon plastically deformed at different temperatures. The temperature dependences of lifetime spectra were measured for all as-deformed and annealing samples. The experimental results indicate that there are three kinds of defects (vacancy clusters, dislocationbound vacancies and undisturbed dislocations) induced by deformation. The size and concentration of vacancy-clusters depend on the strain temperature in the case of similar strains and strain rates. Dislocationbound vacancies were quite stable. They could not be annealed out thoroughly after thermal treatment at 1300 8C. At sample temperatures below 120 K, regular dislocation segments have a significant influence on positron trapping. Their effect as positron shallow traps influences significantly the course of the measured average positron lifetime.