IEEE Electron Device Letters
Author:
Keywords:
germanium (ge), interface traps, low-frequency (lf) noise, oxide traps, pmosfets, high-k gate, 1/f noise, mos-transistors, hfo2, dielectrics, mosfets, performance, interlayers, mobility, behavior, Science & Technology, Technology, Engineering, Electrical & Electronic, Engineering, germanium (Ge), low-frequency (LF) noise, pMOSFETs, HIGH-K GATE, 1/F NOISE, HFO2, MOSFETS, PERFORMANCE, MOBILITY, BEHAVIOR, IMPACT, LAYER, SI, 0906 Electrical and Electronic Engineering, Applied Physics, 4009 Electronics, sensors and digital hardware
Abstract:
The low-frequency noise of pMOSFETs fabricated in epitaxial germanium-on-silicon substrates is studied. The gate stack consists of a TiN/TaN metal gate on top of a 1.3-nm equivalent oxide thickness HfO2/SiO2 gate dielectric bilayer. The latter is grown by chemical oxidation of a thin epitaxial silicon film deposited to passivate the germanium surface. It is shown that the spectrum is of the 1/f(gamma) type, which obeys number fluctuations for intermediate gate voltage overdrives. A correlation between the low-field mobility and the oxide trap density derived from the 1/f noise magnitude and the interface trap density obtained from charge pumping is reported and explained by considering remote Coulomb scattering.