In this paper, we present results on the formation of He-cavities in Si in the presence of vacancies and hydrogen produced by electron cyclotron resonance (ECR) high-density hydrogen plasma treatment. Epitaxial Si (111) samples were first implanted with 1.55 MeV He ions at a dose of 5´10 16 cm -2 . Subsequent annealing at 800 °C for 30 min creates a band of cavities around the He projected range. This band is mainly made up of big elongated cavities in the middle surrounded by a high density of small ones. Other defects (mainly dislocations) have also been observed within and beneath the cavity band. Additional hydrogen plasma treatment, however, changes the morphology of the He-cavities. Plasma hydrogenation tends to increase both the width of cavity band and the cavity size, while, the density of cavities decreases. Moreover, with the plasma hydrogenation step, the cavities are accompanied by a significant concentration of dislocation loops. Such effects have been interpreted in terms of the vacancy-type defects and atomic hydrogen introduced by plasma hydrogenation, and thus their interactions with He-cavities. We have confirmed the generation of high concentrations of vacancies by hydrogen plasma treatment through positron annihilation spectroscopy (PAS) measurements.
Cz p-type Si (100) samples were implanted at room temperature with 160 keV He ions to a dose of 5´10 16 cm -2 and were then followed by 80 keV Si ion implantation at different doses ranging from 10 14 to 5´10 15 cm -2 . Cross-sectional transmission electron microscopy (XTEM) were carried out to study the effects of self-ion implantation induced defects on the thermal evolution of He cavities during subsequent annealing at temperatures from 800 °C to 1150 °C for 1 hour. Our results clearly show that high level of self-ion implantation induced defects can significantly inhibit thermal growth of He cavities. The inhibition effects preferentially occur in the side of cavity band towards the surface. The results suggest that the ejection of interstitials during annealing can go into the He defect region, and interacts with He-vacancy clusters or He cavities there. The capture of interstitials by He cavities is also confirmed by the dissolution of high dose Si ion induced end of range (EOR) defects after high temperature annealing at 1150°C.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.