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It is shown that single-mode fluorosilicate optical fibers fabricated with the aid of modified chemical vapor deposition exhibit a significant decrease in the radiation resistance when 1 mol % GeO2 is introduced into the silica-glass core. Elimination of chlorine and OH group impurities in the silica glass of the core of the fluorosilicate single-mode fiber leads to a relatively low level of radiation-induced attenuation. Prior to radiation processing, the loss factors of optical fiber are 0.18 and 0.3 dB/km at wavelengths of 1.55 and 1.31 μm, respectively. The dependence of optical loss of such fibers on the bend diameter ranging from 6 to 12 mm is studied.

This article concerns experimental and simulation results on nonstable latchups (SLs) in CMOS integrated circuits (ICs) under pulsed laser irradiation. Different transient responses in elements of the p-n-p-n structure and irregular ionization distribution on the IC surface are the main reasons for non-SLs. Radiation experimental test results are presented as well as a discussion of non-SL mechanisms.

The paper concerns experimental results on external conditions such as temperature, voltage supply, current limit, and features of the power circuit on latchup occurrence under uniform laser irradiation.

In an Integrated Circuit with high SEL holding voltage, pulsed-laser radiation sensitivity was found to change due to TID irradiation. The impact of TID on the DUT SEL holding voltage and SEL sensitivity was investigated.

The paper discusses the features and the possibilities of the under-development scanning confocal microscope in tasks of non-destructive examination of semiconductor electronics using the method of confocal microscopy with an emphasis on the possibility of studying the material and internal structure. The described technique allows studying integrated circuits from the substrate side of integrated circuits. This work is part of a global task and is devoted to mathematical modeling of the scanning process.

Singe event effect (SEE) simulation in modern integrated circuits (ICs) by femtosecond laser irradiation through the substrate allows eliminating a lot of problems connected to the presence of multiple opaque metal layers above the IC active layer. With this irradiation geometry, the proper wavelength of laser radiation should be chosen to generate sufficient amount of nonequilibrium charge in the active layer on the one hand, and to avoid significant laser energy losses in the thick substrate on the other hand. In this paper several typical microelectronic ICs were selected to investigate the dependence of SEE generation effectiveness on the laser wavelength when irradiating through the substrate of various thickness. It was found, that the most appropriate laser wavelength for the silicon substrate thicknesses of 300 to 800 μm lies in the 1030 to 1070 nm range

The aim of this work was to develop a fabrication process of single-mode polarization-maintaining germanosilicate optical fibers with elliptical core (GOFEC) doped with 20 mol % GeO2. The fiber preform was fabricated by MCVD method. The low-oxygen central piece of the core in the preform was removed by high-temperature chemical gas-phase etching. The influence of γ-radiation with a dose rate of 1 Gy/s on the optical losses in GOFEC at a wavelength of 1550 nm and at 25°C and −60°C were investigated. Their radiation resistance at −60°C is proved to surpass that of the existing analogous fibers. It has been found that the radiation-induced attenuation in such highly doped GeO2 single-mode fibers is higher than that in multimode fibers. In contrast to multimode fibers, radiation resistance in single-mode fibers depends on the material of the core and cladding. As to the radiation resistance, these GOFEC are comparable with the fiber of PANDA type with a pure silica glass core.

The radiation hardness results of light emitting diodes (LED) in green, blue and red regions of the spectrum and in white, based on InGaN, GaN and AlInGaP structures are presented. The technical aspects of monitoring parameters during exposure are described, and LEDs response to various radiation exposures are given.

Oxygen deficiency in a silica glass core of fluorosilicate optical fiber manufactured by the modified chemical vapor deposition method provides extra high level of its radiation resistance. Gamma-radiation-induced attenuation (RIA) in such a fiber increases with decreasing both the test temperature (from + 25 to minus 60 °C) and the wavelength (from 1.55 to 1.31 μm). After exposure to radiation, RIA completely disappears at the room temperature. At the temperature of minus 60 °C, the optical losses restore much worse. RIA increases due to the superposition of Rayleigh scattering and absorption, with the latter decreasing with increasing wavelength.

A review of laser devices that are currently used to perform hardness evaluation of microelectronic devices that are exposed to heavy charged particles, with respect to local radiation effects is presented. A brief classification of ionization effects in semiconductors caused by single heavy charged particles is provided. The possibility of using focused pulse-laser radiation for research on these effects is validated. A general approach to the construction of test systems that are based on picosecond lasers with sharp beam focusing systems is presented. The technical requirements for the basic modules of such systems are substantiated. The parameters of the domestic PICO-3 and PICO-4 laser test devices are compared to their foreign analogues and the means of their further improvement are given. The technical and operational characteristics of these devices that allow them to be used in various research tasks that require selective (with a submicron spatial resolution) object excitation by ultrashort laser pulses and recording of its response with exact timing of the moment of excitation, as well as for various precise technological operations, are discussed.

The paper presents experimental results about transient single event latch-up (SEL) in CMOS ICs. The rail span collapse is the main reason of nonstationary SELs. A decrease of the voltage applied to n-p-n-p structure can be caused an additional current both in SEL state and in IC dynamic mode.

Experimental results are presented for different CMOS ICs, evidencing latent damage induced by single event latch-up. Additive and non-additive destructive effects are analyzed.

The presented experimental results reflect the ionizing breakdown effect in CCD sensor under the fluence of heavy charged particles confirmed on a simulating laser facility. The effect primary analysis has been carried out, the critical parts have been highlighted.

The advances of the picosecond and femtosecond laser installations utilization for radiation hardness evaluation of semiconductor electronics for space applications are presented. The modern “local laser irradiation” method for single event effects testing of semiconductor devices, not requiring calibration by ions is described. The essence of the local approach is in irradiating the sample sensitive volume, positioned at some distance from the focus plane, where the beam becomes divergent. Due to such optical effects as single or multiple reflections, scattering, diffraction, reflections from air-SiO2 boundary, interference, absorption in n+/p+/poly-Si layers and reflection from bottom side of substrate, the laser light partially penetrates into the sensitive volume, screened by the presence of multilayer metallization,n+/p+ nearsurface layers, regions of polysilicon in the passivation layer, etc. Assuming single-photon absorption the relationship between the laser pulse energy and the excess charge actually generated in irradiated sensitive volume is obtained by the measurement of the electrical response, thus taking into account the non-uniform optical losses and avoiding additional calibration by ions. Some results, obtained using both the front-side and the backside local irradiation of devices, are presented. Comparison with the results obtained using focused laser radiation with subsequent calibration by ions showed that the laser-only measurements, based on local irradiation, give the correct estimates of radiation hardness parameters. It is shown that the use of backside local irradiation method is the most suitable for laser single event effects tests.

The results of computation-experimental modeling of single-event latchup effects under the laser radiation focused on the IC crystal backside—the substrate side—are presented. Possibilities of applying the technique of local laser irradiation to evaluate equivalent linear energy transfer of heavy ions in the case of the laser irradiation from the substrate side of IC crystal are analyzed. The experimental results obtained using the pulsed laser installation and accelerators of charged particles for a series of modern LSI ICs are compared.

Experimental setup based on visible and NIR spectral range microscope with laser port and picosecond laser is developed for silicon integrated circuit (IC) failure analysis. The possibility of visualizing the topology of the submicron technology silicon structures from the back side of the crystal through the substrate is shown. Main features of new setup are demonstrated by some results of backside focused pulsed laser beam initiated latchup effect study. The possibility of the localization of the latchup sensitive areas under focused laser irradiation is shown. NIR light emission accompanying the latchup effect is observed and analyzed. The practical aspects of NIR microscopy for failure analysis under backside laser irradiation are discussed.

MRAM cell permanent failures was observed along with SEL under laser and ion beam irradiation. Sample preparation for back side was proposed to safe MRAM functionality and to allow focused laser irradiation though the substrate of MRAM die.

The technique of flip-chip ICs SEE testing based on a joint use of focused laser facility and heavy ions with medium range of 100 μm … 200 μm is presented.

The article discusses the automated system for measurement of optical and electrical parameters of optoelectronic devices such as laser diodes and photodiodes using a National Instruments PXI-platform and Ophir laser power sensors. The typical connection circuit and method of parameters control are described.

A policy is described for predicting the rate of single-event effects (SEEs) in ICs exposed to high-energy ions and heavy charged particles. The procedure involves an assessment of the radiation environment for the ICs and an estimation of their SEE sensitivity parameters, with the latter based on tests and computer simulations.

New experimental results using both ion and laser facilities are presented to analyse four multiple cell upset (MCU) mechanisms in SRAMs. Equations describing basic MCU mechanisms were provided.

IC's SEE sensitivity may depend on temperature. Traditional ion irradiation methods have some limitations, which laser SEE technique can overcome. In this work, SEE laser test results for various temperatures are discussed.

As a result of analyzing more than 60 types of the modern transceivers ICs, the most sensitive functional units and the critical operation modes upon exposure the space radiation (especifically, TID and SEE effects) were identified

Four parts of opamp OP1177ARZ manufactured by Analog Devices have been tested. The chips have been compared visually and with specialized software. Forms of ionization response in three checkpoints have been registered, and maps of response amplitudes on the crystal surface have been constructed. It has been determined , that crystals samples are various in spite of identical crystals marking. So TID behavior of various samples has been observed.

In this work the analysis of possible approaches to SEU-hardness testing for SRAM with error correction were conducted. Efficiency of the aproach proposed by Aeroflex was evaluated, and the results of experimental investigation for 16 Mbit SRAM under heavy ion and focused laser irradaition were provided.

The installations for laser testing of microelectronic elements (first of all - integrated circuits) of devices for space applications for hardness to local radiation effects from heavy charged particles are presented. The possibility of a focused pulsed laser radiation application to the study of local radiation effects, caused by single heavy charged particles, is explained. The fundamentals of an approach to the construction of test sets, based on the picosecond and femtosecond lasers and systems for focusing their radiation, are considered. The main technical requirements for the basic modules of sets for laser testing (laser wavelength and pulse duration and repetition rate, spatial beam parameters and minimal spot size, speed of object movement and so on) are substantiated. All worked out sets have a full-featured software for the operational management of all modules of the laser test facility, including the positioning of the object, to provide feedback from the measurement results of the reaction of the object on the laser excitation. The parameters of developed laser hardware and software systems and their foreign counterparts are compared. Further improvement directions for laser testing tools are briefly outlined. The discussion is also presented of described hardware technical and operational characteristics, allowing to use it for a variety of scientific research studies, requiring selective (with submicron spatial resolution) object excitation by ultrashort laser pulses and recording responses to this effect with the exact timing of the moment of excitation, as well as to perform a variety of high precision technological operations.

The new SEE laser simulation facility based on femtosecond laser source with tunable pulse duration is presented, and its most important features are discussed. The influence of laser pulse duration on simulation results is observed.

SEU, SEL and SET sensitivity estimation results using laser technique in dependency of TID effects are presented and discussed.

Single event upset (SEU) and single event latchup (SEL) laser testing results of SRAM CY62256 using both focused and local laser irradiation techniques are presented. Variable laser wavelength was used for SEU and SEL threshold linear energy transfer (LET) estimation. The backside laser irradiation technique was also applied. Laser testing results were compared to heavy ion testing ones. depends on SEE type and the laser irradiation technique being used. We investigated SEL and SEU effects in SRAM CY62256NLL using focused and local laser irradiation techniques and different laser wavelengths (1.064, 1.0, 0.9 and 0.85 μm). We also used the backside laser irradiation in addition to the front side one when making the experiment with the wavelength of 1.064 μm. II. EXPERIMENTAL TECHNIQUE The experimental investigation was carried out using two laser facilities providing the wavelengths from 0.53 μm up to 1.064 μm (Table 1). In this work PICO-3 laser facility was used at 1.064 μm wavelength. PICO-4 operated at the wavelengths of 1.0 μm, 0.9 μm and 0.85 μm.

 Abstract — Compendium of SEU, SEL, SET, SEB and SEGR comparative results under ion irradiation and focused laser beam are presented. The possible sources of discrepancies between ion and laser results and the ways of data correction are discussed.

Technical characteristics of "PICO-4" SEE simulation facility utilizing a tunable picosecond laser source are presented. Its capabilities aimed on simulation of single event effects under space environment in Si, GaAs, SiGe etc. microelectronic devices are discussed.

The results on SEE sensitivity of 0.5 $\mu$ m SOI CMOS microprocessor are presented and discussed. The comparative analysis of different test techniques (particle accelerator, pulsed laser technique and $^{252}$ Cf fission source) is provided for the cache. The possible sources of discrepancies between test results and the ways of data correction and methods of testing techniques' accuracy improvement are discussed.

The results of local laser simulation for estimation of SEE parameters are presented. Simulation method is based on the local laser irradiation of VLSI by measuring response in power supply circuits and determining laser threshold energy of SEE.