Trap density in Ge-on-Si pMOSFETs with Si intermediate layers

Author

Fobelets, Kristel ; Rumyantsev, Sergey L. ; Shur, Michael S. ; Vincent, Benjamin ; Mitard, Jerome ; De Jaeger, Brice ; Simoen, Eddy ; Hoffmann, Thomas Y.

Author_Institution

Dept. of Electr. & Electron. Eng., Imperial Coll. London, London, UK

fYear

2011

fDate

12-16 June 2011

Firstpage

317

Lastpage

320

Abstract

The 1/f noise of three different Ge channel p-type MOSFETs, epitaxially grown on silicon substrates was measured between 1 and 100 Hz. The difference between the p-MOSFETs is the thickness of the interfacial Si layer between Ge channel and gate stack that is needed to passivate the Ge channel. The gate stack consists of SiO₂/HfO₂/TaN/TiN layers. Noise in all structures complies with the McWorther carrier number fluctuation model. The magnitude of the noise power spectral density of the drain current was found to increase with decreasing Si interfacial layer thickness. The extracted trap densities are between 10¹⁸ and 10¹⁹ cm^-1 eV^-1. These values are currently at the lower end of the range of other MOSFETs with high-k dielectric gate stacks.

Keywords

MOSFET; carrier density; electron traps; elemental semiconductors; germanium; hafnium compounds; high-k dielectric thin films; hole traps; semiconductor device noise; silicon; silicon compounds; tantalum compounds; titanium compounds; 1/f noise measurement; Ge-Si; McWorther carrier number fluctuation model; Si; SiO₂-HfO₂-TaN-TiN; drain current; gate stack; high-k dielectric gate stacks; interfacial silicon layer; intermediate layers; noise power spectral density; pMOSFET; trap density; Insulators; Logic gates; MOSFETs; Noise; Noise measurement; Silicon; Ge-on-Si; MOSFET; low frequency noise;

fLanguage

English

Publisher

ieee

Conference_Titel

Noise and Fluctuations (ICNF), 2011 21st International Conference on

Conference_Location

Toronto, ON

Print_ISBN

978-1-4577-0189-4

Type

conf

DOI

10.1109/ICNF.2011.5994331

Filename

5994331