Boron Partitioning Coefficient above Unity in Laser Crystallized Silicon

• Main Authors: Patrick C. Lill, Morris Dahlinger, Jürgen R. Köhler
• Format: Article
• Language: English
• Published: MDPI AG 2017-02-01
• Series: Materials
• Subjects: solute trapping; rapid solidification; silicon; laser melting; boron doping
• Online Access: http://www.mdpi.com/1996-1944/10/2/189

Boron pile-up at the maximum melt depth for laser melt annealing of implanted silicon has been reported in numerous papers. The present contribution examines the boron accumulation in a laser doping setting, without dopants initially incorporated in the silicon wafer. Our numerical simulation models laser-induced melting as well as dopant diffusion, and excellently reproduces the secondary ion mass spectroscopy-measured boron profiles. We determine a partitioning coefficient k p above unity with k p = 1 . 25 ± 0 . 05 and thermally-activated diffusivity D B , with a value D B ( 1687 K ) = ( 3 . 53 ± 0 . 44 ) × 10 − 4 cm 2 ·s − 1 of boron in liquid silicon. For similar laser parameters and process conditions, our model predicts the anticipated boron profile of a laser doping experiment.