EXTRACTION OF THE OXIDE CHARGE DENSITY AT FRONT AND BACK INTERFACES OF SOI NMOSFET DEVICES

摘要

This work presents a new method to extract the oxide charge densities at front (Q_(0x1)) and back (Q_(0x2)) interfaces in fully depleted SOI nMOSFETs. The proposed method exploits the influence of the front and back gate voltages on the back and front channel current regime respectively. To extract Q_(0x2), the drain current curve is measured as a function of the back gate voltage V_(GB) with the front interface inverted. When the back interface condition changes due to the back gate voltage, kinks occur in the front drain current for specific VGB biases and these are used by the method. Similarly, the back drain current as a function of the front gate voltage V_(GF) with the back interface inverted shows some kinks at specific VGF which are used by the method to extract Q_(0x1). MEDICI simulations were used to support the analysis and the method was applied experimentally.