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Circuit parameters and configuration are very important when studying the synergistic effects total dose/SET. We explore a method combining dynamic parameter measurement and spectrum analysis which lead to a better understanding of this complex phenomenon. In this paper symbolic circuit analysis is used to obtain the relationship between input, output and noise injection due to photocurrent generation in the form of a rational function using symbolic variables in the complex frequency domain. This simulation technique was able to predict the impact of (i) total dose level, (ii) circuit parameters, and (iii) the injected energy on the ASET shapes. Basic mechanisms as field collapse and collection efficiency were also predicted and assessed. [ABSTRACT FROM PUBLISHER]

GaAs diode dark currents are correlated over a very large proton energy range as a function of displacement damage dose (DDD). The linearity of the dark current increase with DDD over a wide range of applied voltage bias deems this device an excellent candidate for a DD dosimeter. Additional proton testing performed in situ enabled error estimate determination to within 10% for simulated space use. [ABSTRACT FROM PUBLISHER]

Heavy-ion induced single-event measurements for n-channel InAsSb quantum-well metal-on-insulator field-effect transistors (QW-MOSFETs) are demonstrated for a range of gate bias conditions. Marked differences were observed in the transient current profile and the resultant collected charge at the drain nodes of the transistors depending on whether the devices were biased in accumulation or depletion with different gate voltages (VGS). While the amplitude of the transients decreases as the transistors are biased into accumulation, a long decay tail of transients with enhanced charge collection is obtained compared to that in depletion. To analyze the transient response, a calibrated TCAD device simulation equipped with a heavy ion induced ionization model has been developed, which shows excellent agreement with the measured results for the entire range of evaluated gate bias conditions. The simulation analysis reveals that the charge-collection enhancement phenomenon in an n-channel InAsSb QW-MOSFET is associated with the increased bipolar gain due to the increased hole storage in accumulation. [ABSTRACT FROM PUBLISHER]

We show the single-event effect characteristics of a production-level embedded resistive memory. The resistive memory under investigation is a reduction-oxidation random access memory embedded inside a microcontroller. The memory structure consists of Ir top electrode, Ta2\ O{5 - \delta} /TaOx metal-oxide, and TaN bottom electrode. The radiation testing focused on the resistive memory array and peripheral circuits, while other portions of the microcontroller were shielded against the ion beam. We found that the resistive memory array is hardened against heavy ion and pulsed-laser-induced bit upsets. However, the microcontroller is susceptible to single-event functional interrupts due to single-event upsets in the resistive memory peripheral control circuits, which comprise of CMOS elements. Furthermore, the resistive memory architecture is not susceptible to functional failures during write, which is problematic for flash memories due to radiation-induced charge pump degradation. [ABSTRACT FROM PUBLISHER]

This paper presents an investigation of the impact of single-event transients (SETs) and total ionization dose (TID) on precision voltage reference circuits designed in a fourth-generation, 90-nm SiGe BiCMOS technology. A first-order uncompensated bandgap reference (BGR) circuit is used to benchmark the SET and TID responses of these voltage reference circuits (VRCs). Based on the first-order BGR radiation response, new circuit-level radiation-hardening-by-design (RHBD) techniques are proposed. An RHBD technique using inverse-mode (IM) transistors is demonstrated in a BGR circuit. In addition, a PIN diode VRC is presented as a potential SET and TID tolerant, circuit-level RHBD alternative. [ABSTRACT FROM PUBLISHER]

Ion-induced, time-resolved charge-collection measurements for p-channel AlGaSb/InGaSb field-effect transistors are reported for a range of gate and drain bias conditions. The transient response reveals two distinct contributions: a faster initial response (< 1~ns) followed by a slower, > 10~ns, relaxation. The slower contribution depends sensitively on the applied gate bias, is suppressed when the gate is made more positive toward depletion, and is identified with an enhanced source-drain current in which more charge is collected than is deposited by the ion. A model consistent with the experimental measurements suggests that the dynamics of the enhancement processes are associated with the trapping and detrapping dynamics of electrons in the AlGaSb barrier materials. [ABSTRACT FROM PUBLISHER]

This paper investigates total ionizing dose (TID) effects on the piezoelectric properties of lead zirconate titanate (PZT). The capacitance and contact voltage of thin-film, PZT-based relays were measured following incremental ^60Co TID irradiations. The devices were held in several different bias conditions, during exposure. The direction of the biasing electric field during exposure, along with the polarization prior to exposure, has a measurable impact on post-irradiation operating voltage of the relay. In all cases, the switching voltage, as obtained via the peak values in a capacitance versus voltage sweep, shifted in a direction that would minimize the switching electric field in the direction of pre-exposure polarization. These effects were observed to be both significantly greater than the shifts experienced by a set of control samples, as well as reversible via aging at room temperature. The devices display remarkable robustness, operating during active TID exposure [dose rate = 855.6 rad(Si)/s], failing at a TID greater than 15 Mrad(Si). [ABSTRACT FROM PUBLISHER]

The Synergistic effect between Total Ionizing Dose (TID) and Analog Transient Radiation Effects in Electronics (ATREE) in an operational amplifier (LM124) is investigated. A predictive methodology, based on a previously developed ATREEs simulation tool, is used to model the synergistic phenomena. This phenomenon is simulated for the first time and the duration of the ATREEs' is found to be identical to those measured experimentally. ATREEs induced by high dose-rate X-ray pulses are investigated using a flash X-ray facility. The ATREEs induced in the LM124 operational amplifier configured in three different bias configurations are investigated and simulated. [ABSTRACT FROM PUBLISHER]

The switched dose rate technique has been proposed as an accelerated test technique for enhanced low-dose-rate sensitivity. The physical mechanisms at play when this technique is applied are investigated in this paper. The variation of Not and Nit is characterized using gated lateral pnp transistors to understand the kinetics of device degradation related to differences in mechanisms between high dose rate and low dose rate irradiations. [ABSTRACT FROM PUBLISHER]

The Synergistic effect between TID and ATREEs (Analog Transient Radiation Effects on Electronics) in an operational amplifier (opamp) (LM124) is investigated for three different bias configurations. An accelerated irradiation technique is used to study these synergistic effects. The impact of TID on ATREEs is found to be identical regardless of whether the irradiation is performed at low dose rate or whether the dose rate is switched from high to low using the Dose Rate Switching (DRS) technique. The correlation between the deviations of the opamp's electrical parameters and the changes of ATREE widths is clearly established. [ABSTRACT FROM AUTHOR]

Analog Transient Radiation Effects in Electronics (ATREE) induced by high dose-rate X-ray pulses are investigated using a flash X-ray facility. The ATREEs induced in a LM124 operational amplifier configured in three different bias configurations are investigated. A predictive methodology, based upon a previously developed ASET simulation tool, is used to model the ATREE phenomena. A semiempirical physical model is used to perform the correlation between the duration of the parasitic pulse signal induced in the LM124 and an equivalent value of the high dose-rate X-ray pulse level. [ABSTRACT FROM AUTHOR]

It is shown that the variety of shapes of the input current versus dose curve observed in several ICs is due to circuit effects, depending on the architecture, the value of the currents and the bias conditions. When stages are cascaded, the degradation of the second stage may add or subtract current to the collector current of the input transistor. The variations of the collector currents can be evaluated using the variations of the supply current. It is then possible to model the compensation effects using basic equations and study the impact of irradiation conditions. In some cases, the effect of biasing the circuit during irradiation is to reduce the compensation mechanism leading to an stronger increase in the input current. When a peak shaped degradation curve is recorded, annealing may either induce an additional degradation or a recovery depending on which side of the peak irradiation has brought the circuit. [ABSTRACT FROM PUBLISHER]