Use of p- and n-type vapor phase doping and sub-melt laser anneal for extension junctions in sub-32 nm CMOS technology
Nguyen, N. D × Rosseel, Eveline Takeuchi, S Everaert, J-L Yang, L Goossens, J Moussa, A Clarysse, T Richard, O Bender, H Zaima, S Sakai, A Loo, R Lin, J. C Vandervorst, Wilfried Caymax, M #
Thin Solid Films vol:518 pages:S48-S52
6th International Conference on Silicon Epitaxy and Heterostructures (ICSI-6) Los Angeles, CA, MAY 17-22, 2009
We evaluated the combination of vapor phase doping and sub-melt laser anneal as a novel doping strategy for the fabrication of source and drain extension junctions in sub-32 nm CMOS technology, aiming at both planar and non-planar device applications. High quality ultra shallow junctions with abrupt profiles in Si substrates were demonstrated on 300 mm Si substrates. The excellent results obtained for the sheet resistance and the junction depth with boron allowed us to fulfill the requirements for the 32 nm as well as for the 22 nm technology nodes in the PMOS case by choosing appropriate laser anneal conditions. For instance, using 3 laser scans at 1300 degrees C, we measured an active dopant concentration of about 2.1 x 10(20) cm(-3) and a junction depth of 12 nm. With arsenic for NMOS, ultra shallow junctions were achieved as well. However, as also seen for other junction fabrication schemes, low dopant activation level and active dose (in the range of 1-4 x 10(13) cm(-2)) were observed although dopant concentration versus depth profiles indicate that the dopant atoms were properly driven into the substrate during the anneal step. The electrical deactivation of a large part of the in-diffused dopants was responsible for the high sheet resistance values. (C) 2009 Elsevier B.V. All rights reserved.