Incorporation of tin in boron doped silicon for reduced deactivation of boron during post-laser-anneal rapid thermal processing

Abstract

Strain compensation in boron-indium coimplanted laser thermal processed silicon J. Appl. Phys. 97, 093525 (2005); 10.1063/1.1891282 Thermal stability of dopants in laser annealed silicon Redistribution and electrical activation of ultralow energy implanted boron in silicon following laser annealingThe supersaturated and metastable boron produced by laser anneal could deactivate during post-laser-thermal-cycles and lead to undesirable performance degradation. The effect of tin incorporation on the thermal stability of boron was studied for the first time and suppressed boron deactivation during post-laser-rapid-thermal-anneal was observed with tin coimplantation. High resolution x-ray diffraction measurement indicates that the tensile strain caused by a high boron concentration was reduced by the introduction of tin, which effectively reduces the strain energy and therefore, enhances the thermal stability of boron in post-laser-anneal rapid thermal processing.

Strained SiGeSn formed by Sn implant into SiGe and pulsed laser annealing

“…We note that the active B concentration is improved in this range of laser energy density where Sn substitutionality is improved. In the presence of Sn, activation of B is enhanced, 10 and similar observation has been reported for B activation in the presence of Ge. 11 At higher laser energy ͑Ͼ400 mJ cm −2 ͒, significant diffusion of Sn and B occurs, leading to a lower average B concentration, contibuting to a slight increase in R S .…”