Heavy ion linear energy transfer measurements during single event upset testing of electronic devices

A heavy ion beam diagnostic system installed at the Brookhaven Single Event Upset Test Facility is described. Calibration of the system with the help of a-particles, essential for linear energy transfer (LET) measurements, is discussed. Measured LET values for 20 different ions, including /sup 7/Li, /sup 9/B, /sup 12/C, /sup 16/O, /sup 19/F, /sup 28/Si, /sup 32/S, /sup 35/Cl, /sup 40/Ca, /sup 45/Sc, /sup 48/Ti, /sup 56/Fe, /sup 58/Ni, /sup 63/Cu, /sup 74/Ge, /sup 79/Br, /sup 107/Ag, /sup 127/I, /sup 197/Au, and /sup 235/U, with energies between 0.5 and 8.5 MeV/AMU but not exceeding 400 MeV for the heaviest ions, are presented in both graphical and numerical forms. Results are compared to predictions of the TRIM-90 simulation program, with an average difference between the measured and calculated values of 2/spl plusmn/6%.