4 Irradiation Facility and Setup

The heavy ion species used for the original SEE studies on this product were provided and delivered by the TAMU Cyclotron Radiation Effects Facility^[3] using a superconducting cyclotron and advanced electron cyclotron resonance (ECR) ion source. Ion beams are delivered with high uniformity over a 1-inch diameter circular cross sectional area for the in-air station. Uniformity is achieved by means of magnetic defocusing. The intensity of the beam is regulated over a broad range spanning several orders of magnitude. For the bulk of these studies, ion fluxes between 10⁴ and 10⁵ ions/s-cm² were used to provide heavy ion fluences between 10⁶ and 10⁷ ions/cm². For these experiments Praseodymium (Pr) ions were used. Ion beam uniformity for all tests was in the range of 91% to 98%.

For correlation SEL and SET testing, heavy ion species were provided and delivered by the MSU Facility for Rare Isotope Beams [9] using a linear particle accelerator ion source. Ion beams were delivered with high uniformity over a 17mm × 18mm area for the in-air station. A current-based measurement is performed on the collimating slits, which intercept 90 to 95% of the total beam, and this measurement is cross-calibrated against Faraday cup readings. These measurements are real-time continuous and establish dosimetry and integrated fluence. In-vacuum and in-air scintillating viewers are used for measurement of the beam size and distribution. An ion flux of 10⁵ ions / s-cm² was used to provide heavy ion fluences to 10⁷ ions / cm².