A new self-consistent modeling approach to investigating MOSFET degradation

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.<<ETX>>

[1]  J. Ueda,et al.  Mechanism of hot carrier induced degradation in MOSFET's , 1986, 1986 International Electron Devices Meeting.

[2]  James Stasiak,et al.  Trap creation in silicon dioxide produced by hot electrons , 1989 .

[3]  T. Ning.  Capture cross section and trap concentration of holes in silicon dioxide , 1976 .

[4]  F. Hofmann,et al.  The charge pumping method: Experiment and complete simulation , 1989 .

[5]  W. Hansch,et al.  The Hot-Electron Problem in Submicron MOSFET , 1988, ESSDERC '88: 18th European Solid State Device Research Conference.

[6]  A. v. Schwerin,et al.  A new approach to calculate the substrate current and oxide injection in a metal-oxide-semiconductor field-effect transistor , 1989 .

[7]  J. M. Andrews,et al.  Electrochemical Charging of Thermal SiO2 Films by Injected Electron Currents , 1971 .

[8]  F. Lau,et al.  Hot-carrier drifts in submicrometer p-channel MOSFET's , 1987, IEEE Electron Device Letters.

[9]  A. Bhattacharyya,et al.  Mechanism of degradation of LDD MOSFETs due to hot-electron stress , 1988 .

[10]  S. Bibyk,et al.  Simulation of hot-electron trapping and aging of nMOSFETs , 1988 .

[11]  W. Hansch,et al.  Gate Currents and Device Degradation : Carrier Transport in Gate Oxides of MOSFET's , 1988, ESSDERC '88: 18th European Solid State Device Research Conference.

[12]  C. Werner,et al.  Hot-electron and hole-emission effects in short n-channel MOSFET's , 1985, IEEE Transactions on Electron Devices.

[13]  W. Hansch,et al.  The relationship between Oxide charge and device degradation: A comparative study of n- and p- channel MOSFET's , 1987, IEEE Transactions on Electron Devices.

[14]  P. Heremans,et al.  Hot-carrier effects in n-channel MOS transistors under alternating stress conditions , 1988, IEEE Electron Device Letters.