Work Function Fluctuation Induced by Random Orientation, Shape, and Size of Metal Grain in 16-nm-Gate High-k/ Metal Gate Bulk FinFET Devices

Y.-Y. Chen, S.-C. Hsu, C.-Y. Chen, W.-T. Huang, C.-M. Yang, L.-W. Chen and Y. Li
National Chiao Tung University, TW

Keywords: metal grain, random work function, random orientation, random size, random shape, bulk FinFET, 3D device simulation

Summary:

In this work, we study the impact of nanosized random metal gate’s work function fluctuation in DC characteristic fluctuation in the 16-nm bulk planar MOSFET and fin-type field effect transistor (FinFET) devices using an experimentally calibrated 3D device simulation. The method of localized work function fluctuation simulation with random-shape generating technique enables us to estimate the nanosized grain’s random effects of FinFET and MOSFET with TiN/HfO2 gate stacks. We further study the effect of different shape and size of the metal grain on device characteristic fluctuation. The result of this study shows characteristic fluctuation can be strongly suppressed by FinFET device and minimal metal grain size.