The transient enhanced diffusion of ultralow energy implanted B is reported in this letter. The mechanism giving rise to an enhancement of the diffusion during postimplantation anneal is investigated in detail by monitoring the diffusion of B as a function of temperature in the range 600–750 °C, for implant energies of 500 eV and 1 keV. The contribution of several classes of defect clusters to the anomalous diffusion phenomenon has been detected and interpreted. Both an ultrafast diffusion, occurring during the ramp-up of the thermal process, and a transient enhancement of the diffusion with characteristic decay times shorter by orders of magnitude than the known transient enhanced diffusion lifetimes, have been evidenced. The activation energy for the enhanced diffusion has been measured and found to be 1.7 eV.

We have investigated the thickness increase of buried oxide layers in silicon-on-insulator structures by thermal oxidation of the top silicon layer. A thermodynamic model is derived based on the experimental observation that oxidation introduces an oxygen concentration into silicon which is above its solubility limit. Experiments on buried oxide growth by thermal oxidation of the top silicon layer were performed with specially designed bond-and-etchback silicon-on-insulator structures in the temperature range between 1100 and 1200°C. The results obtained are compared to the thermodynamic model and to data from other growth experiments. The different buried oxide growth rates observed for different types of silicon-on-insulator material are discussed in terms of different silicon self-interstitial supersaturations which are induced in the top silicon layer during oxidation. InfroductionSilicon-on-insulator (SOl) technology is regarded as promising for high-density complementary metal oxide ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 131.215.225.9 Downloaded on 2015-06-22 to IP

In this paper an extensive characterization of the electrical activation of ultra-low energy implanted boron in silicon is reported. The Spreading Resistance Profiling technique has been used, in a suitable configuration, for measuring doped layers shallower than 100 nm, in order to extract the carrier concentration profiles. The dependence on the implant energy, dose, and annealing temperature allowed us to gain more insight into the mechanisms responsible for the electrical activation at implant energies below 1 keV. By measuring the electrical activation as a function of time for several annealing temperatures, the thermal activation energy for the electrical activation of the dopant was achieved. It slightly depends on the implant dose and it is in the range of 2–3 eV. In particular, for an implant dose of 1×1014/cm2 it is 2.0 eV, close therefore to the 1.7 eV activation energy found [Napolitani et al., Appl. Phys. Lett. 75, 1869 (1999)] for the enhanced diffusion of ultra-low energy implanted boron. The best conditions to maximize electrical activation, while minimizing diffusion, are identified and junction depths of ∼50 nm with sheet resistance below 500 Ω reported. These data are reported and their implication for the fabrication of future generation devices is discussed.

Impact of the end of range damage from low energy Ge preamorphizing implants on the thermal stability of shallow boron profiles