The heavy-ion species used for the SEE
studies on this product were provided and delivered by two facilities:
- Texas A&M University (TAMU)
Cyclotron Radiation Effects Facility using a K500 superconducting cyclotron and
an advanced electron cyclotron resonance (ECR) ion source. At the fluxes used,
ion beams had good flux stability and high irradiation uniformity over a 1in
diameter circular cross-sectional area for the in-air station. Uniformity is
achieved by magnetic defocusing. The flux of the beam is regulated over a broad
range spanning several orders of magnitude. For these studies, ion flux of 5.21
× 104 to 6.23 × 104 ions/cm2·s was used to
provide heavy-ion fluences of 1.00 × 107. The TAMU facility
uses a beam port that has a 1-mil Aramica window to allow in-air testing while
maintaining the vacuum within the particle accelerator. The in-air gap between
the device and the ion beam port window was maintained at 40mm for all
runs.
- Michigan State University (MSU)
Facility for Rare Isotope Beams (FRIB) using a K500 superconducting cyclotron
(KSEE) and an advanced electron cyclotron resonance (ECR) ion source. At the
fluxes used, ion beams had good flux stability and high irradiation uniformity
as the beam is collimated to a maximum of 40mm × 40mm square cross-sectional
area for the in-air and vacuum scintillators. Uniformity is achieved by
scattering on a Cu foil and then performing magnetic defocusing. The flux of the
beam is regulated over a broad range spanning several orders of magnitude. For
these studies, ion flux of 7.74 × 104 to 1.05 ×
105 was used to provide heavy-ion fluences of 1.00 ×
107. The KSEE facility uses a beam port that has a
3-mil polyethylene naphthalate (PEN) window to allow in-air testing while
maintaining the vacuum within the particle accelerator. The in-air gap between
the device and the ion beam port window was maintained at 60mm for all
runs.
For the experiments conducted for this report, two ions were used, 165Ho
and 169Tm. Both were used to obtain LETEFF of
75MeV×cm2/mg. The total kinetic energies for the ions were:
- 165Ho = 2.474GeV (15
MeV/nucleon)
- Ion uniformity for these
experiments was between 92% and 94%
- 169Tm = 3.295GeV (19.5
MeV/nucleon)
- Ion uniformity for these
experiments were between 79% and 91%
Figure 4-1 shows the
TPS7H3024EVM-CVAL in front of the beam line at the TAMU facility.