Paul J. McWhorter

Learn More
A new technique is presented for separating the threshold-voltage shift of an MOS transistor into shifts due to interface states and trapped-oxide charge. Using this technique, the radiation responses of MOS capacitors and transistors fabricated on the same wafer are compared. A good correlation is observed between p-substrate capacitors and n-channel(More)
The physical mechanisms that produce rebound have been identified. The positive increase in threshold voltage during a bias anneal is due to annealing of oxide trapped charge. Rebound can be predicted by measuring the contribution to the threshold voltage from radiation-induced interface states immediately after irradiation.
Data loss and permanent damage resulting from the irradiation of SNOS (polySilicon-Nitride-Oxide-Silicon) nonvolatile memory transistors fabricated with current SNLA EEPROM processing are examined. It is shown that these transistors can retain data for ten years after a 500 krad irradiation, and can be programmed and function properly following a 1300 Mrad(More)
The nature of disruptive and sustaining technologies is sufficiently different to require different activities for the commercialization of these technology categories. Few theorists have developed conceptual schemes about the different methods of commercializing these technologies. The authors take the first steps in investigating these differences by(More)
A quantitative model is developed that can accurately predict the threshold voltage shift, and hence data loss, in SNOS nonvolatile memory transistors over a wide range of dose rates. The model accounts for both the time dependent and radiation induced mechanisms leading to data loss. Experimental measurements are made to verify the validity and accuracy of(More)
The feasibility of using a 10-keV x-ray source as a cornerstone of a hardness assurance program is demonstrated for several of Sandia's integrated-circuit technologies. We present test structure and functional part data that illustrates how an x-ray source may be used for wafer lot acceptance for silicon-gate CMOS devices that either employ guard-bands or(More)
  • 1