Analytical Modeling of Short-Channel Fully-Depleted Triple Work Function Metal Gate (TWFMG) SOI MESFET

In this paper, a new structure: triple work function metal gate SOI MESFET, intended for integration into the deep-submicron CMOS technology, is proposed. The gate of the device consists of three different materials which are laterally merged into one. The difference in the work function of dissimilar gate materials introduces two step changes in the profile of channel potentials which screens the threshold-defining region of the channel from the impact of drain potential. Therefore, the effects associated with DIBL are significantly alleviated. On the basis of exact solution of the Poisson equation in the channel region, an analytical subthreshold model for the device is developed. Using the analytical data, the device has been characterized and compared with conventional device in terms of potential function, DIBL, threshold voltage roll-off, and subthreshold swing. The TCAD simulator ATLAS from Silvaco has been used to validate the analytical results. The feasibility of device fabrication is also demonstrated.

Automated summary

In this paper, a new structure of triple work function metal gate SOI MESFET device is proposed to alleviate the impact of drain potential and reduce DIBL effects. An analytical subthreshold model based on the exact solution of the Poisson equation in the channel region is developed and compared with conventional devices. The feasibility of device fabrication is demonstrated by using the TCAD simulator ATLAS from Silvaco.