> 10(20) cm(-3) n-doping in Ge by Sb/P Co-implants: n(+)/p Diodes with Improved Rectification

Title> 10(20) cm(-3) n-doping in Ge by Sb/P Co-implants: n(+)/p Diodes with Improved Rectification
Publication TypeBook Chapter
Year of Publication2010
AuthorsKim, J, Bedell, SW, Sadana, DK
EditorHarame, D, Ostling, M, Masini, G, Krishnamohan, T, Bedell, S, Reznicek, A, Boquet, J, Yeo, YC, Caymax, M, Tillack, B, Miyazaki, S, Koester, S
Book TitleSige, Ge, and Related Compounds 4: Materials, Processing, and Devices
Volume33
Pagination201 - 204
Abstract

One of the greatest challenges for fabricating a Ge channel n-MOSFET is to achieve high n-type dopant activation within the source and drain regions. Currently, p(+) doping greater than 10(20) cm(-3) can be routinely achieved which is close to the theoretical solid solubility limit of B in Ge. However, typical n(+) doping of Ge is limited to less than 5x10(19) which is far below the solid solubility limit of P in Ge. This work is aimed at achieving n(+) doping of greater than 10(20) cm(-3) in Ge. In this paper, we describe a Sb and P co-implantation process to enhance n(+) activation in Ge. N-carrier concentration more than 1.0x10(20)/cm(3) has been demonstrated by this method. Furthermore, higher forward bias current in Ge n(+)/p junction diode is obtained from n(+) formation by Sb and P co-implantion, as a consequence of the high n-type dopant activation in Ge.