P. Calvel

An empirical model for predicting proton induced upset

This paper presents an empirical model for proton induced Single Event Upset (SEU). This model is based on heavy ion data, and will improve the previous two parameters Bendel model. Application to various parts is presented.

Separation of effects of oxide-trapped charge and interface-trapped charge on mobility in irradiated power MOSFETs

An effective approach to separating the effects of oxide-trapped charge and interface-trapped charge on mobility degradation in irradiated MOSFETs is demonstrated. It is based on analyzing mobility data sets that have different functional relationships between the radiation-induced-oxide-trapped charge and interface-trapped charge. Separation of the effects of these two trapped charge components is only possible if they are not linearly dependent. A significant contribution of oxide-trapped charge to mobility degradation is demonstrated and quantified. >

Temperature and angular dependence of substrate response in SEGR [power MOSFET]

This work examines the role of the substrate response in determining the temperature and angular dependence of Single-Event Gate Rupture (SEGR) in a power MOSFET. Experimental data indicate that the likelihood of SEGR increases when the temperature of the device is increased or when the incident angle is made closer to normal. In this work, simulations are used to explore this influence of high temperature on SEGR and to support physical explanations for this effect. The reduced hole mobility at high temperature causes the hole concentration at the oxide-silicon interface to be greater, increasing the transient oxide field near the strike position. In addition, numerical calculations show that the transient oxide field decreases as the ions angle of incidence is changed from normal. This decreased field suggests a lowered likelihood for SEGR, in agreement with the experimental trend. >

Charge generation by heavy ions in power MOSFETs, burnout space predictions and dynamic SEB sensitivity

The transport, energy loss, and charge production of heavy ions in the sensitive regions of IRF 150 power MOSFETs are described. The dependence and variation of transport parameters with ion type and energy relative to the requirements for single event burnout in this part type are discussed. Test data taken with this power MOSFET are used together with analyses by means of a computer code of the ion energy loss and charge production in the device to establish criteria for burnout and parameters for space predictions. These parameters are then used in an application to predict burnout rates in a geostationary orbit for power converters operating in a dynamic mode. Comparisons of rates for different geometries in simulating SEU (single event upset) sensitive volumes are presented. >

Simulation aided hardening of N-channel power MOSFETs to prevent single event burnout

2D MEDICI simulator is used to investigate hardening solutions to single-event burnout (SEE). SEE parametric dependencies such as carrier lifetime reduction, base enlargement, and emitter doping decrease have been verified and a p/sup +/ plug modification approach for SEE hardening of power MOSFETs is validated with simulations on actual device structures.

Comparison of experimental measurements of power MOSFET SEBs in dynamic and static modes

A study to determine the single-event burnouts (SEBs) sensitivity for burnout of IRF-150 power MOSFETS in both static and dynamic modes in terms of LET threshold and cross section is described. The dynamic tests were conducted with a power converter which was designed for actual space application. The results were compared with static measurements which were made during the exposure to the heavy ions. The data showed that the dynamic mode was less sensitive than the static by two orders of magnitude in cross section. It was also observed that ions with a range less than 30 microns did not produce destructive burnout in the dynamic mode even when their LET exceeded the threshold value. The extent of physical MOSFET damage in the destructive, dynamic tests appeared to correlate with the ion LET and source-drain voltage. >

Measurement of a cross-section for single-event gate rupture in power MOSFETs

The heavy-ion fluence required to induce Single-Event Gate Rupture (SEGR) in power MOSFETs is measured as a function of the drain bias, V/sub DS/, and as a function of the gate bias, V/sub GS/. These experiments reveal the abrupt nature of the SEGR-voltage threshold. In addition, the concepts of cross-section, threshold, and saturation in the SEGR phenomenon are introduced. This experimental technique provides a convenient method to quantify heavy-ion effects in power MOSFETs.

Total dose effects on gate controlled lateral PNP bipolar junction transistors

A gate controlled lateral PNP bipolar device has been designed in a commercial BiCMOS process to investigate its sensitivity to radiation-induced degradation. New experimental and simulated results concerning total dose effects are presented. The improved radiation hardness of this device working in its accumulation mode is shown. The influence of the gate potential during irradiation is studied as well as the effect of the gate potential on the degraded current characteristics.

Application of test method 1019.4 to nonhardened power MOSFETs

The applicability of MIL-STD-883D Method 1019.4 to predicting the low-dose-rate radiation response of nonhardened power MOSFETs has been investigated. Method 1019.4 works well in providing bounds for the threshold-voltage shift. However, it is not intended to provide an estimate of the actual /spl Delta/V/sub T/ due to low-dose-rate irradiation. A modified method is proposed which can yield more information on the threshold-voltage shift at low dose rates for power MOSFETs. >

Experimental evidence of the temperature and angular dependence in SEGR [power MOSFET]

The temperature and angular dependence of Single-Event Gate Rupture (SEGR) experiments, conducted on power DMOS transistors, show that a normal incident angle favors SEGR and elevated temperature is insignificant. Both the oxide and substrate response play a major role in determining the SEGR sensitivity.