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The solid phase epitaxial growth technique appears to be a promising method for achieving junction depths and sheet resistance values low enough to meet the performance specifications of the 65 and 45 nm node for boron, BF 2 , and BF 3 doping profiles in amorphous silicon. Room-temperature implants of these three dopant species into Si͑100͒ preamorphized by 74 Ge + ͑30 keV, 1.0 ϫ 10 15 cm −2 ͒ lead to boron concentration profiles that fulfill the technological requirements. It was found that even for ultrashallow junctions the time for the regrowth process at 650°C has to be optimized with regard to the implanted species in the range between 5 and 60 s, especially when fluorine is present. The thermal stability of the boron profile distribution that meets 65-nm-node requirements was evaluated by subsequent thermal anneals simulating the thermal effects expected for typical silicidation processes. For a more detailed investigation, the postannealing temperatures ranged from 250 to 1050°C with times from a few to several hundred seconds. All the junctions were analyzed by four-point probe and selected samples by secondary ion mass spectroscopy, transmission electron microscopy, and high-resolution electron microscopy.The combination of doping and activation technology is expected to provide solutions for highly activated, shallow, and abrupt dopant profiles required for advanced logic device technology beyond the 90-nm node. 1 In contrast to spike and/or flash annealing, a simple approach for the formation of ultrashallow junctions with boron consists of preamorphizing the substrate prior to dopant implantation followed by a low-temperature solid phase epitaxial growth process ͑SPEG͒. The SPEG technique currently appears to be a promising method for achieving junction depth and sheet resistance values low enough to meet the performance specifications for the 65-and 45-nm node. The optimal process for high activation during SPEG involves annealing at ϳ650°C for 5-60 s in an inert ambient. 2 The main advantages of the SPEG technique is that it has been extensively studied for at least three decades. In general it is rather simple and requires only conventional implant and rapid thermal processing equipment. It is also a low-temperature approach that is thermally compatible with advanced materials such as high-k dielectrics and metal gates. In this paper we present some of our recent results on the formation of ultrashallow junctions using the SPEG technique. Additionally, data for technology nodes beyond 90 nm are also presented in a sheet resistance vs junction depth matrix, including data from current literature of various techniques.However, the thermal stability of activated junctions is a critical consideration for front-end complementary metal oxide semiconductor ͑CMOS͒ manufacturing. Therefore, in the second part we present a detailed study of boron deactivation during thermal processes after SPEG. Postannealing temperatures were chosen in order to "simulate" typical self-aligned silicide processes for NiSi or...

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The evolution of {113} defects as a function of time and depth within Si implant-generated defect profiles has been investigated by transmission electron microscopy. Two cases are considered: one in which the {113} defects evolve into dislocation loops, and the other, at lower dose and energy, in which the {113} defects grow in size and finally dissolve. The study shows that dissolution occurs preferentially at the near-surface side of the defect band, indicating that the silicon surface is the principal sink for interstitials in this system. The results provide a critical test of the ability of physical models to simulate defect evolution and transient enhanced diffusion.

One of the bottlenecks in the pharmaceutical industry is drug production scaleup, which can be performed by microreactor technology. Such an approach was applied to the synthesis of (Z)-5-(4-hydroxybenzylidene)thiazolidine-2,4-dione, a bioactive aromatic heterocyclic compound belonging to the class of glitazones. n-Propanol was the best solvent and piperidine the best catalyst for the batch reaction, which was completed in only 5.5 h. In the microreactor, the productivity was almost independent of solvent. The microreactor behaved as a plug-flow reactor and operated at a steady state for ten hours without efficiency loss. The results suggest that microreactors may replace batch reactors in scaling up drug production.

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Microreactor technology can help to reduce the time to market new drugs. It was applied to produce (Z)‐5‐benzylidenethiazolidine‐2,4‐dione, a heterocyclic intermediate in the synthesis of various drugs. Ethanol was the optimum solvent and piperidine the best catalyst in the batch process. The continuous/microreactor process exhibited a much better performance than the batch process. The productivity, which was strongly influenced by solvent and temperature, reached a maximum at 160 °C using methanol as solvent. A kinetic/thermodynamic study indicated that the reaction followed the second‐order model and allowed estimating its main thermodynamic parameters. A product recovery protocol was finally proposed. The microreactor proved an efficient alternative to the batch reactor in scaling up the production of active pharmaceutical ingredients.