Title :
A new self-consistent modeling approach to investigating MOSFET degradation
Author :
Hänsch, W. ; Schwerin, A.V. ; Hofmann, F.
Author_Institution :
Siemens AG, Munchen, West Germany
Abstract :
A modeling tool is presented that allows a complete analysis of a DC stress experiment without assuming the location and amount of trapped oxide charges and interface states. To describe the buildup of oxide damage, a semiempirical rate equation approach is outlined. A completely self-consistent calculation is presented of the time dependence of the DC stress experiment. This calculation monitors the amount and location of charges built up in the 2-D oxide region during the stress line. The model includes competing trap mechanisms such as the formation of interface states and fixed oxide traps. This permits consideration of n- and p-channel MOSFETs with the same model. The calculations are compared to DC stress measurements on n- and p-channel devices with gate lengths of 0.65 mu m that are typical for 16-Mb DRAMs.<>
Keywords :
DRAM chips; MOS integrated circuits; VLSI; insulated gate field effect transistors; integrated memory circuits; semiconductor device models; 0.65 micron; 16 Mbit; 16-Mb DRAMs; 2-D oxide region; DC stress experiment; DC stress measurements; MOSFET degradation; buildup of oxide damage; competing trap mechanisms; complete analysis; completely self-consistent calculation; fixed oxide traps; formation of interface states; location of charges; modeling tool; n-channel MOSFETs; p-channel MOSFETs; self-consistent modeling approach; semiempirical rate equation; stress line; submicron gate lengths; time dependence; trapped oxide charges; Degradation; Electron traps; Equations; Guidelines; Interface states; MOSFET circuits; Random access memory; State feedback; Stress measurement; Substrates;
Journal_Title :
Electron Device Letters, IEEE
