|2011/06/08 歡迎 Dr. Piyas Samanta 蒞臨演講，講題：New Experimental Insights in Degradation of SiO2 and HfO2/SiO2 Stack under Electrical Stress|
2011/06/08 歡迎 Dr. Piyas Samanta 蒞臨演講，講題：New Experimental Insights in Degradation of SiO2 and HfO2/SiO2 Stack under Electrical Stress
New Experimental Insights in Degradation of SiO2 and HfO2/SiO2 Stack under Electrical Stress
Dr. Piyas Samanta
Physics Department, Vidyasagar College for Women, Kolkata, INDIA
To reduce the excessive leakage current through sub 3 nm SiO2 gate dielectric in contemporary submicron CMOS technology, insulating layers with high dielectric constant are being considered as possible replacement of SiO2 as the gate dielectric. Among various high-k dielectrics, HfO2 has become the one of the potential candidates.
Like other high-k oxides, HfO2 also have some intrinsic limitations because of their increased bond ionicity and oxygen atom coordination. The presence of excess fixed oxide charge and interface states in HfO2 leads to enhanced scattering with channel carrier resulting reduced FET mobility compared to SiO2 MOSFETs. Also, the turn-on voltage of the HfO2 devices is higher compared to SiO2 devices. Oxide defects are critical in device operation. However, relative comparison of the oxide degradation and TDDB in SiO2 and HfO2/SiO2 stack has not yet been studied.
The purpose of the present investigation is to give better insights in degradation of SiO2 and HfO2/SiO2 stack of similar EOT at a given stress voltage and/or at a given Eox.