Platinum Germanosilicide Contacts Formed on Strained and Relaxed $\hbox{Si}_{1 - x}\hbox{Ge}_{x}$ Layers

Emre Alptekin,Veena Misra,Mehmet C Ozturk,Casey Joe Kirkpatrick

doi:10.1109/ted.2009.2018159

Emre Alptekin, Veena Misra + Show 2 more

https://doi.org/10.1109/ted.2009.2018159

Copy DOI

Export

Save

Cite

Abstract
Full-Text
Similar Papers

Abstract

Listen

Contact resistivity is a key contributor to the parasitic series resistance of nanoscale MOSFETs. Since the contact resistivity is an exponential function of the Schottky barrier height, new contact materials that can provide smaller barrier heights to source-drain junctions are needed. Platinum germanosilicide (PtSi 1-x Ge x ) is of interest as a contact material to the recessed Si 1-x Ge x junctions of p-channel MOSFETs due to the large work function of platinum silicide (PtSi). In this paper, we explore the impact of in-plane biaxial compressive strain in Si 1-x Ge x layers on PtSi 1-x Ge x formation and the impact of the PtSi 1-x Ge x on the strain in Si 1-x Ge x . The parameters considered in this paper include the Ge content, the thickness of the Si 1-x Ge x epitaxial layer, and the PtSi 1-x Ge x thickness. The results show that the resistance, surface morphology, and the crystalline structure of the PtSi 1-x Ge x films are independent of the strain in the original Si 1-x Ge x layer. The results also indicate that PtSi 1-x Ge x does not influence the strain in the Si 1-x Ge x layer. The barrier-height measurements suggest the presence of Fermi-level pinning, and the pinning position is independent of the strain in the alloy, and it is primarily determined by the Ge concentration. As a result of Fermi-level pinning, hole Schottky barrier height of PtSi 1-x Ge x -Si 1-x Ge x contacts is 0.1-0.2 eV higher than that of the PtSi-Si contacts.

Full Text