Modeling Voids in Silicon
M. Hasanuzzaman, Y.M. Haddara, A.P. Knights
McMaster University, CA
void, modeling, silicon
Voids in silicon are used for gettering transition metals and may be used to detect point defect injection. High energy implants can create a separation between vacancies and interstitials making a vacancy rich region near the surface and the interstitial rich region at the bulk. The vacancies at the vacancy rich region can agglomerate together and form voids. In this paper we propose a moment-based model for void growth and dissolution in Si. We have adapted the model from the work on interstitial capture in 311 clusters and implemented it using the FLOOPS-ISE process simulator. We compare the simulation results with previously published data on void formation in Si. The samples were implanted with MeV Si and annealed in the temperature range 750-1000°C for different anneal times. Our model solves for the total number of vacancies in voids, the void density and the concentration of vacancies in the small vacancy clusters. We assume that the release of the vacancy from the voids is the rate limiting step for dissolution of voids, and we account for faster dissolution of smaller voids. We were able to fit the experimental data for multiple anneals for each temperature using a consistent set of fitting parameters and got excellent fits in all the cases.
Nanotech 2008 Conference Program Abstract