DTMOS power switch in 28 nm UTBB FD-SOI technology

Abstract

Ultra-Thin Body and Box (UTBB) Fully Depleted Silicon-On-Insulator (FD-SOI) Technology has become mainstream in the industry with the objective to serve a wide spectrum of mobile multimedia products [1]. Transistors (fig 1) are fabricated in a 7nm thin layer of silicon sitting (Tsi) over a 25nm buried oxide (Tbox). Thanks to its better electrostatic control [2]; UTBB FD-SOI technology brings a significant improvement in terms of performance and power saving, complemented by an excellent responsiveness to power management design techniques for energy efficiency optimization. However, looking for a steady increase in performance for a voltage supply value constantly lowered with the evolution of technologies, BULK or FD-SOI, involves a decrease in the threshold voltage (Vt) and leads to an increase of the stand-by leakage current, requiring the implementation of a leakage current reduction technique.