Performance Analyses of Planar Schottky Barrier MOSFETs with Dual Silicide Layers at Source/Drain on Bulk Substrates and Material Studies of ErSi_x/CoSi_2/Si Stack Interface

A dual silicide layer structure is proposed for Schottky barrier metal-oxide-semiconductor field effect transistors (MOSFETs) on bulk substrates. The source/drain regions are designed to be composed with dual stacked silicide layers, forming different barrier heights to silicon channel. Performance comparisons between the dual barrier structure and the single barrier structure are carried out with numerical simulations. It is found that the dual barrier structure has significant advantages over the single barrier structure because the drive current and leakage current of the dual barrier structure can be modulated. Furthermore, the dual barrier structure's performance is nearly insensitive to the total silicide thickness, which can relax the fabrication requirements and even make an SOI substrate unnecessary for planar device design. The formation of ErSi_x/CoSi_2 stacked multilayers has been proved by experiments.