A study of the electrical characteristics of nanoscale Si/SiGe/Si heterostructure PMOSFET

In this paper the electrical characteristics of a P channel MOSFET which utilizes a Si/SiGe/Si heterostructure is studied. Since a SiGe layer is employed next to the Si layer in the channel region, two inversion layers are formed in this device which provides two characteristics threshold voltages. The lattice mismatch between SiGe and Si leads to a compressive strain in the Si1-xGex layer. The hole mobility increases as a result of this induced compressive strain in Si1-xGex layer. We have studied the effects of the Ge mole fraction in SiGe layer on the ID-VDS characteristics.This investigation also shows that the gate capacitance, the drain current and the maximum transconductance are enhanced when the Ge mole fraction increases

Keywords:

PMOSFET , Si/Si1-xGex , strain , heterointerface , Ge mole fraction