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A method to carry out a priori simulations of pulsed-laser-induced single-event effects experiments is reported. Nonlinear optical simulations are conducted to model the 3-D distributions of charge from a laser pulse. These pulsed-laser-induced charge distributions are then incorporated into a charge transport solver to model the movement of charge as the device returns to a steady state. The output of the simulation infrastructure is a current transient from which collected charge and the temporal characteristics of the transient can be determined. This complete approach to modeling, which includes full device structure information, nonlinear optical energy deposition, and the subsequent movement of optically generated charge in a device and measurement circuit, allows for direct comparison between experimental and simulated current transients. A large-area silicon diode was used as the test vehicle, and good agreement was found between simulations and experiments in both total injected charge as well as temporal characteristics. Importantly, the a priori simulation approach does not require knowledge from prior heavy-ion testing, making it a predictive tool with broad versatility and minimal reliance on approximations. [ABSTRACT FROM AUTHOR]

Heavy-ion, focused X-ray, and pulsed laser single-event transient (SET) experiments are performed on a silicon epitaxial diode. Collected charge, transient rise times, and transient fall times are calculated and compared between different sources. The transient shape characteristics depend on the source (ion, X-ray, or laser), even when similar amounts of charge are generated. The observed differences are examined and explained in terms of basic charge collection mechanisms. [ABSTRACT FROM AUTHOR]

A sensitive volume is developed using pulsed laser-induced collected charge for two bias conditions in an epitaxial silicon diode. These sensitive volumes show good agreement with the experimental two-photon absorption laser-induced collected charge at a variety of focal positions and pulse energies. When compared to ion-induced collected charge, the laser-based sensitive volume overpredicts the experimental collected charge at low bias and agrees at high bias. A sensitive volume based on ion-induced collected charge adequately describes the ion experimental results at both biases. Differences in the amount of potential modulation explain the differences between the ion- and laser-based sensitive volumes at the lower bias. Truncation of potential modulation by the highly doped substrate, at the higher bias, results in similar sensitive volumes. [ABSTRACT FROM AUTHOR]

A two-photon absorption technique is used to understand the mechanisms of single-event effects (SEEs) in silicon carbide power metal–oxide–field-effect transistors (MOSFETs) and power junction barrier Schottky diodes. The MOSFETs and diodes have similar structures enabling the identification of effects associated specifically with the parasitic bipolar structure that is present in the MOSFETs, but not the diodes. The collected charge in the diodes varies only with laser depth, whereas it varies with depth and lateral position in the MOSFETs. Optical simulations demonstrate that the variations in collected charge observed are from the semiconductor device structure and not from metal/passivation-induced reflection. The difference in the spatial dependence of collected charge between the MOSFET and diode is explained by bipolar amplification of the charge carriers in the MOSFETs. Technology computer-aided design (TCAD) device simulations extend this analysis to heavy-ion-induced charge collection. In addition, there is discussion comparing this analysis with experimental results from prior works that show enhanced charge collection resulting from heavy-ion irradiation. [ABSTRACT FROM AUTHOR]