In this work, a series of 13 boron implants were performed into Czochralski silicon substrates with doses of 2ϫ10 14-1.6ϫ10 15 cm Ϫ2 at energies of 10-80 keV. The boron was deliberately clustered with a 750°C anneal of 10 or 30 min and the electrical activation of the boron implants was determined following a second anneal at 750 or 850°C with a Hall effect system with certain samples also being analyzed with a spreading resistance technique. Analysis of the reactivation rates allows for the determination of the net energy to boron reactivation to be approximately 3.0 eV assuming the reactivation process is mediated by release of a boron interstitial with a migrational energy of 0.3 eV. This results in a critical binding energy of approximately 2.7 eV from the process limiting the dissolution of the most stable boron-interstitial cluster.

The relationships between extended defect evolution and boron diffusion in Si0.77Ge0.23 have been investigated. A SiGe structure was grown by molecular beam epitaxy with a 3×1018atoms∕cm3 boron marker layer positioned 0.50μm below the surface. Samples were ion implanted with 60 keV Si+ at a dose of 1×1014atoms∕cm2 and subsequently annealed at 750 °C for various times. The evolution of extended defects in the near surface region was monitored with plan-view transmission electron microscopy. Secondary ion mass spectroscopy concentration profiles facilitated the characterization of boron diffusion. Boron experiences transient enhanced diffusion regulated by the dissolution of dislocation loops. The maximum diffusion enhancement in Si0.77Ge0.23 is less than that observed in pure Si.

Application of flash-assist rapid thermal processing subsequent to low-temperature furnace anneals Impact of the end of range damage from low energy Ge preamorphizing implants on the thermal stability of shallow boron profiles

Articles you may be interested inDiffusion of co-implanted carbon and boron in silicon and its effect on excess self-interstitials J. Appl. Phys. 111, 073517 (2012); 10.1063/1.3702440 Atomistic analysis of the evolution of boron activation during annealing in crystalline and preamorphized siliconBoron is introduced into silicon via implantation to form p-type layers. This process creates damage in the crystal that upon annealing causes enhanced diffusion and clustering of the boron layer. Reactivation of the boron is not a well-understood process. In this letter we experimentally investigate the effect of the annealing ambient on boron reactivation kinetics. An oxidizing ambient which injects silicon interstitials is compared to an inert ambient. Contrary to published theory, an excess of interstitials does not accelerate the reactivation process.

As device lots become more and more expensive, process modeling is increasingly important. Process simulation and modeling is increasingly sophisticated but the accuracy remains a problem. There is generally a time lag between the introduction of a particular process and its accurate modeling – the problem of “yesterday's technology modeled tomorrow”. For many problems, absolute accuracy isn't required. Relative trends provide excellent information about the process in question. For this reason, process simulation is still a useful technique for guiding process development.