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The aim of this work is to validate experimentally the results of the Monte Carlo Recoil Energy Determination (MC-RED) nuclear physics code used to determine the deposited energy in a silicon volume taking into account the probabilistic approach of the physical phenomenon. A silicon sensor has been used to measure the deposited energy spectrum after an irradiation with a 14 MeV neutron source. Neutrons of 14 MeV were produced by the SAMES accelerator of the Valduc CEA research center. The experimental results were compared with the one obtained by the MC-RED code in the same silicon volume. To compare experiment and simulations, it requires that the complete neutron field be specified. We have to take into account the facility cell environment. Nuclear simulations were performed with the MCNP code to determine with accuracy the energy spectra of neutrons and gamma rays produced by this facility on the sensor. It is shown that the contribution of secondary neutrons is not negligible. Index Terms--Neutron-silicon interactions, neutron source, nuclear physics code, silicon detector, single event upset.

This paper investigates the sensitivity of SOI and Bulk SRAMs to neutron irradiations with energies from 14 to 500 MeV. The technology sensitivity is analyzed with both experiments and Monte Carlo simulations. In particular, simulations include the nuclear interactions of neutrons with both silicon and oxygen nuclei In-St and n-O), in order to investigate the influence of isolation upper layers on the device sensitivity. The device cross-sections are analyzed for mono-energetic neutron irradiations and discussed in terms of nuclear interaction type (n-St and n-O) and distribution of the secondary ion recoils. We also investigate the dimensions of the interaction volume around the sensitive cell as a function of the device architecture. Index Terms--Bulk technologies, SOI technologies, neutron effects, soft error rate (SER), single-event upset (SEU), Monte Carlo methods.

The SEU sensitivity of 0.2 [micro]m fully depleted silicon on ensulator (FD-SOI) devices to proton and neutron irradiations is investigated in a large energy range (14-500 MeV). The comparison to bulk devices with similar gate lengths shows an improvement of a factor of 50 with the presence of body ties. Monte Carlo simulations were performed to confirm that the low sensitivity of FD-SOI is mainly due to the reduced sensitive volume. These results were extrapolated to deca-nanometric technologies to predict the behavior of advanced SOI processes. We found that fully depleted devices will be far less sensitive than partially depleted technologies to the terrestrial radiative environment. Index Terms--Neutron, proton, SEU, SOI, SRAM.

This paper presents a new 3D methodology to simulate Multiple Bit Upsets in commercial SRAMs. Experiments are performed at the Los Alamos neutron facility on 90, 130, and 250 nm SRAMs and compared to Monte-Carlo simulations. A discussion on ions inducing MBUs is also proposed. Index Terms--Bulk, diffusion, Monte-Carlo, multiple bit upsets (MBU), neutron, SEU, SRAM.

A reliable criterion for SEU occurrence simulation is presented. It expresses the relationship existing at threshold between the magnitude and duration of the ion-induced parasitic pulse. This criterion can be obtained by both three-dimensional device and SPICE simulations. Using this criterion, the simulated and experimental SER on 130 and 250 nm technologies are shown to be in good agreement.

The aim of this work is to show the contribution of nuclear events occurring with oxygen nuclei in SRAM-oxide such as Si[O.sub.2] and emphasize that they are likely to increase the soft error rate by about several tens of percent. Recoil energies are calculated with a dedicated subroutine, which accounts for elastic and nonelastic reactions in the 5-150-MeV energy range. SEU cross sections are evaluated using the criterion of critical energy deposited in a cubic sensitive volume. Index Terms--Monte Carlo, neutron, nuclear cross sections, oxygen, passivation layer, recoil, sensitive volume, SEU, silicon oxide, SRAM, silicon.

A Monte Carlo approach is used to obtain statistical information on the effect of the spatial distribution of the numerous secondary ions involved in neutron induced soft error rates (SER). The sorting criteria for the occurrence of upset are derived from a simplification of previous work on full-cell three-dimensional (3-D) SRAM device simulation. The time thus saved allows the treatment of a wide variety of track conditions. The shape and extension of the sensitive region is explored and correlated to the secondary ion properties. Details on the variations of the sensitivity with depth into the sensitive region as well as on the geometrical conditions associated with those tracks that cause upsets are given. Index Terms--Atmospheric neutrons, device simulation, ion tracks, recoils, sensitive volume, single event upset (SEU), soft error rate (SER), SRAM.

Academic 128 x 128 bit structures are simulated to study soft error cross sections induced by high-energy nucleons (n/p) in SRAM memories. The distributions of secondary ions are obtained by the nuclear high energy transport code and analyzed in terms of energy deposited in the sensitive volume of each memory cell. Multiple-bit upset cross sections are compared to single-event upset cross sections, and trends associated to scaling effects are presented. Index Terms--Critical energy, downscaling, HETC, Monte Carlo, multiple-bits upset, nucleon, sensitive volume, single-event upset (SEU), SRAM.

Chemical vapor deposited (CVD) diamond is a very promising material that is extensively studied in many technologies. Thermally stimulated luminescence (TSL) experiments demonstrate that an important thermal quenching phenomenon occurs with microwave plasma chemical vapor deposited diamond. This phenomenon leads to a large discrepancy on the determination of electronic trap parameters. Thermally stimulated conductivity phenomenon is not affected by thermal quenching and allows an easier determination of trap parameters than TSL measurements. The difference between the two ways of computing trap energy is found to be around 4% instead of 28%, which is obtained when thermal quenching fails. [ABSTRACT FROM AUTHOR]

The aim of this work is to validate the results of the Monte Carlo recoil energy determination nuclear physics code used to determine the deposited energy in a silicon volume taking into account the probabilistic approach of the physical phenomenon. A silicon sensor has been used to measure the deposited energy spectrum after an irradiation with a neutron source. The experimental results were then compared with the one obtained by Monte Carlo simulations in the same silicon volume. Experiments and simulations are shown to be in good agreement in the field of interest for soft error rate evaluation that means for deposited energy range leading to memory point upsets in static random access memory. [ABSTRACT FROM AUTHOR]