Electronic Structures of Donor-Acceptor-Donor Trimer Codopants in Silicon
The total energies of donor-acceptor-donor D2A trimer codopants (D = As and Sb, A = B, Al, Ga, In and Tl) in Si and their electronic geometrically stable structures were studied using ab initio calculations in order to propose new dopants for the formation of ultra shallow junctions with high carrier concentrations in the source/drain regions. The results of the calculations indicated that the trimer codopants were formed in Si and were stable. The trimer codopants are also able to activate the inactive complexes As2V and Sb2V by codoping acceptor atoms that occupy vacant sites. In particular, As2Al, As2Ga, Sb2B and Sb2Ga resulted in both shallower donor levels and higher solid solubility compared to traditional single donor atoms such as As and Sb.
Yuhang Yang, Xilong Qu, Yiping Luo and Aimin Yang
N. Kambara and H. Kawanishi, "Electronic Structures of Donor-Acceptor-Donor Trimer Codopants in Silicon", Advanced Materials Research, Vol. 216, pp. 402-407, 2011