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Single Event Transient (SET) current is one of the most interesting issues for understanding and predicting Single Event Effects (SEEs) in real space environments. Since space radiation consists of high energy heavy ions, estimation of the energy dependence of SET currents is required. In order to estimate this effect, we have developed the Transient Ion Beam Induced Current (TIBIC) system combined with collimated high energy ion beams accelerated by AVF Cyclotron. We have demonstrated the function of TIBIC developed here. Using the newly developed TIBIC system and the Technology Computer Aided Design (TCAD) simulator, the influence of ion energy on SET currents is estimated. Index Terms--Collimated beam, single event transient (SET) current, transient ion beam induced current (TIBIC).

Single-event transients are investigated for two voltage regulator circuits that are widely used in space. A circuit-level model is developed that can be used to determine how transients are affected by different circuit application conditions. Internal protection circuits--which are affected by load as well as internal thermal effects--can also be triggered from heavy ions, causing dropouts or shutdown ranging from milliseconds to seconds. Although conventional output transients can be reduced by adding load capacitance, that approach is ineffective for dropouts from protection circuitry. Index Terms--Radiation testing, single-event transient, voltage regulator.

The optical spectral response of Si pin photodiodes was examined after gamma and electron irradiation. We observed both a significant decrease in the peak optical response and peak position with increasing total dose. This effect was successfully explained by modeling the degradation of the minority carrier diffusion length in the base region. The diffusion length damage factor was estimated in the context of the nonionization energy loss (NIEL). A close agreement was found between the observed degradation behavior and that predicted by NIEL. Index Terms--Equivalent displacement damage dose, minority carrier diffusion length, nonionizing energy loss (NIEL), optical spectral response, pin photodiode.

We report on the temperature dependence of the heavy-ion transient-ion beam induced current response of Si epilayer devices from 80 to 300 K. The measurements were performed on a heavy-ion microbeam in conjunction with the new transient-ion beam induced current system developed at the Japan Atomic Energy Research Institute. Furthermore, we perform a detailed comparison with technology computer-aided design (TCAD) simulations and discuss the results in terms of TCAD modeling, experimental procedure, and the implications for temperature-related single-event upset modeling. Index Terms--MeV heavy-ion microbeam, single-event phenomena (SEP), technology computer-aided design (TCAD) simulation, transient current, transient IBIC.

Ion beam induced charge microscopy (IBIC) can be optimized to provide maximum topographical image contrast and insensitivity to ion initiated damage for a given device. The short and long ion range characterizes the resultant charge pulse spectrum, the rate of observable damage, and the IBIC image contrast. Ions, which are restricted within the device depletion layer, produce charge pulses that are less susceptible to ion induced damage than restricted longer range ions.

We report on recent development on the CSIRO Nuclear Microprobe (NMP) towards catering for long exposure mapping required for large area scanning. A new data collection system based on Labview FPGA highly co-ordinated with beam transport sits at the heart of the upgrade. These upgrades are discussed and an example of the systems use for μ-Particle Induced X-ray Emission (PIXE) analysis in the area of complex ore geo-electrochemistry is briefly described.

Describes the use of millielectron volt alpha particles to generate ion beam induced charge images with a signal to noise level. Effect of ion induced damage and ion channeling on measured charge pulse height; Role of charge pulses in producing low signal noise level; Influence of electronic energy loss rate on larger charge pulse production.

Abstract: Using the single ion hit Transient Ion Beam Induced Current (TIBIC), the transient current generated in n+p 6H–SiC diodes by 15MeV-oxygen (O4+) microbeams was measured. The signal peak of the transient current increases, and the fall-time, which is defined as the decay time from 90% to 10% of the transient current, decreases with increasing applied reverse bias. The charge generated in n+p 6H–SiC diodes was estimated from the integration of the TIBIC signal. As the result, the value of collected charge increases with increasing applied reverse bias up to 90V, and the saturation of the collected charge was observed at reverse biases above 100V. At reverse biases below 110V, the charge generated in the deeper region as compared to the depletion layer length is collected due to the funneling effect. Almost all charge generated in n+p SiC diodes by 15MeV-O4+ irradiation can be collected when the length of depletion layer becomes longer than the projection range of 15MeV-O4+ ions. No significant difference in transient behavior and charge collection is observed between gamma-ray (0.26MGy) irradiated and non-irradiated samples. [Copyright &y& Elsevier]