Logo image
A resultant stress effect of contact etching stop layer and geometrical designs of poly gate on Nanoscaled nMOSFETs with a Si1-xGex channel
 

A resultant stress effect of contact etching stop layer and geometrical designs of poly gate on Nanoscaled nMOSFETs with a Si1-xGex channel

Chang-Chun Lee, Chuan-Hsi Liu, Zih-Han Chen Tzai-Liang Tzeng
Journal of Nanoscience and Nanotechnology, Vol.15(3), pp.2173-2178
01/2015
CESL Finite element analysis (FEA) SiGe channel Bioengineering Chemistry (all) Biomedical Engineering Materials Science (all) Condensed Matter Physics
In this research, an n-type metal-oxide-semiconductor field effect transistor (nMOSFET) device with a SiGe channel exerted by the combination of a contact etching stop layer (CESL) and silicon germanium (Si 1-x Ge x ) channel stressors is proposed. To explore the foregoing mechanical effect on the stress distribution of nMOSFETs within the channel region, a process-oriented simulated technique is adopted for the concerned nMOSFET device. The loading sources are a 1.1 GPa tensile CESL (t-CESL) and a SiGe channel structure constructed with 0%, 22.5%, and 25%, germanium (Ge) mole fractions. The results of the simulation show that the stress components of the Si 1-x Ge x channel evidently increase when the Ge mole fraction within a Si 1-x Ge x layer is increased. A pulling force exerted on the protruding gate structure by the CESL layer that causes dominant bending deformation and channel stress variation behaviors is a major reason for this phenomenon. Therefore, the degree of bending effect caused by the protruding gate structure is concluded as being the key to determining the trends and stress magnitudes of the Si 1-x Ge x device channel.
1
Logo image