Very Fast and Primingless Single-Crystal-Diamond X-Ray Dosimeters

Abstract

X-ray dosimeters were developed by tailoring novel injecting diamond-like-carbon/Pt/Au contacts on single-crystal high-purity diamond films. A dark resistivity of (5.6 ± 0.1) × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">14</sup> Ω · cm and no appreciable presence of deep traps in the bandgap confirmed a very low defect density in the diamond films. The dosimeters resulted to be primingless (i.e., no need of preactivation) and characterized by high sensitivity [(58.20 ± 3.26) × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> C · Gy <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> ] and linear response to X-ray dose rate, produced by a molybdenum target. Transient X-ray modulated analysis allowed the determination of fast-trap influence and the estimation of very fast response times (~10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> s), at electric fields ≥ 3 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> V/cm.