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The propagation of single event transients (SET) is measured and modeled in SOI and bulk inverter chains. The propagation-induced pulse broadening (PIPB) effect is shown to determine the SET pulse width measured at the output of long chains of inverters after irradiation. Initially, narrow transients, less than 200 ps at the struck inverter, are progressively broadened into the nanosecond range. PIPB is induced by dynamic floating body effects (also called history effects) in SOI and bulk transistors, which depend on the bias state of the transistors before irradiation. Implications for SET hardness assurance, circuit modelling and hardening are discussed. Floating body and PIPB effects are usually not taken into account in circuit models, which can lead to large underestimation of SET sensitivity when using simulation techniques like fault injection in complex circuits. Index Terms--Chains of inverters, heavy ions, propagation induced pulse broadening, pulsed laser, single event transients.

This paper presents a simulation and experimental study of the analog single-event transient sensitivity of wide bandwidth operational amplifiers. Architecture effects are presented that could influence ASIC design and COTS selection. Index Terms--ASET, high-speed, laser, laser cross section, laser mapping, op-amp, simulation, SPA.

A clock and data recovery (CDR) circuit dedicated to satellite embedded high-speed data links is implemented in a 0.13 [micro]m CMOS technology. Its radiation hardening is obtained thanks to an innovative architecture based on an injection-locked oscillator (ILO) associated with a phase-alignment circuit. Its low single-event transient (SET) sensitivity is shown thanks to heavy-ion and laser testing. Index Terms--Clock and data recovery (CDR), CMOS technology, heavy-ion testing, high-speed data links, injection-locked oscillators (ILO), laser testing, radiation hardening by design, single-event transients (SET).

SET-induced oscillations were measured on a stable linear-regulator that uses the LM124 op-amp in its regulation block. Simulations showed that single events act as stimuli that initiate a large-signal oscillation in the LM124 differential amplifier and compensation capacitor path. Laser testing validated the analysis and confirmed that transistors connected to the compensation capacitor are the most vulnerable. Index Terms--Linear voltage regulator, macro-model, Single Event Oscillation.

Two important RF building blocks, a low noise amplifier and a voltage-controlled oscillator, were designed and fabricated in a 0.13 [micro]m CMOS process using radiation-hardened by design techniques. Both circuits exhibit only minimal degradation with total dose when the parts are irradiated up to 500 krad (Si[O.sub.2]). Laser beam testing results indicate that the output spectrum of the two circuits has no noticeable change with laser energy up to 200 pJ. Index Terms--Annular gate transistor, low noise amplifier (LNA), radiation hardened by design (RHBD), single-event transients, total ionizing dose, voltage-controlled oscillators (VCO).

Implemented in a 0.25 [micro]m SiGe technology, a 5.2 GHz Injection Locked Oscillator (ILO) for Radio-Frequency (RF) applications is shown to be intrinsically radiation-hardened. Design principles and laser-based testing results are presented. Index Terms--Injection locked oscillators (ILOs), radiation hardening, radio frequency (RF), SiGe technology, single-event transients (SETs).

Device simulations of laser induced SEU in an SRAM cell are performed with pulse durations from 100 fs to 100 [micro]s. SEU threshold energy is notably dependent on the pulse duration. Two regimes are identified and modeled analytically and electrically. Index Terms--Critical charge, device simulation, laser testing, pulse duration, single event upset.

The concept of charge efficacy is introduced as a measure of the effectiveness of incident charge for producing single-event upsets. Efficacy is a measure of the single-event upset (SEU) sensitivity within a cell. It is illustrated how the efficacy curve can be determined from standard heavy-ion or pulsed laser SEU cross-section data, and discussed how it can be calculated from combined charge collection and circuit analysis. Upset rates can be determined using the figure of merit approach, and values determined from the laser cross-sections or from the mixed-mode simulations. The standard integral rectangular parallel-piped (IRPP) method for upset rate calculation is re-examined assuming that the probability of upset depends on the location of the hit on the surface. It is concluded that it is unnecessary to reformulate the IRPP approach. Index Terms--Figure of merit (FOM), heavy ion, picosecond pulsed laser, proton, SEU rates, single event simulation, single event upset (SEU).

A new category of analog single-event transients (SETs) with millisecond-long durations have been experimentally observed in the LM6144 operational amplifier. It is the first time that events with such extreme widths are under investigation in a linear integrated circuit. Relying on heavy-ion broadbeam tests, picosecond pulsed lasers diagnostics, and computer-assisted circuit modeling, we uncover the mechanisms and causes of these anomalous voltage transients. The identification of the problematic area of the IC reveals that the bias/startup circuitry is sensitive to energetic ionizing particles and can be responsible for corrupted circuit operations when subjected to a heavy-ion strike. A circuit hardening solution with minimal impact on the layout and the electrical performances of the op amp are proposed to mitigate this effect. Index Terms--Analog single-event transients, heavy-ion broadbeam, LM6144 operational amplifier, millisecond pulse width, multistable circuit, picosecond pulsed lased, radiation hardening by design.

A test vehicle has been specially realized to demonstrate that different physical mechanisms are responsible for single-event upset phenomena within an elementary memory cell, depending on the impact location. Validation is performed using pulsed laser equipment. Index Terms--Laser mapping, SEU, SRAM.