Uniaxial stress efficiency for different fin dimensions of triple-gate SOI nMOSFETs

Multiple-Gate Field-Effect Transistors, a.k.a. MuGFETs, are composed by a silicon "fin" structure, with a metal gate wrapped on three of the four silicon faces, composing the triple-gate device. The MuGFET device shows good gate-to-channel coupling, reducing short channel effects and improving the current drive [1]. The nMOSFET performance can be further improved by mechanically stressing the silicon fin, using the contact etch stop liner (CESL) technique. The stress transferred from the nitride layer to the fin is dependent on the dimensions of the fin. The mechanic properties of the materials are also important to the final stress transfer. In this work, the focus is on how the fin dimensional variations influence the stress efficiency and how the analog behavior of the triple-gate devices is affected. Four different fin structures are studied by 3D numerical simulation. Experimental results of standard and strained devices were used to validate the simulations for reference devices.