Heteroepitaxy of Nd0.67Sr0.33MnO3 on silicon for bolometric x-ray detector application

TLDR

The study reports detailed fabrication of a bolometric X‑ray detector, its response to LCLS photon illumination, and an improved growth scheme on silicon using YSZ, CeO₂, and Bi₄Ti₃O₁₂ buffer layers. The detector is built from epitaxial Nd₀.₆₇Sr₀.₃₃MnO₃ thin films grown on Si by pulsed laser deposition, incorporating the aforementioned buffer/template layers. The sensor’s thermal response varies linearly with optical calibration laser energy, and its signals from optical and X‑ray pulses at LCLS are similar, confirming the design and marking the first practical use of colossal magnetoresistive manganite bolometers.

Abstract

We have recently reported the design concept and sensor fabrication for a novel bolometric x-ray detector based on a rare earth manganite material for application as a total energy monitor for the Linac Coherent Light Source (LCLS) free electron laser at the Stanford Linear Accelerator Center (SLAC). The detector employs epitaxial thin films of Nd(0.67)Sr(0.33)MnO(3) grown on Si by pulsed laser deposition. In this paper we report details of the fabrication of the actual detector, its response characteristics under photon illumination from LCLS, and improvements in the growth scheme of the sensor material on Si using a buffer/template layer scheme that employs yttria-stabilized zirconia, cerium oxide (CeO(2)), and bismuth titanate (Bi(4)Ti(3)O(12)). The thermal sensor response changes linearly with the energy of an optical calibration laser as expected, and the signals from optical and x-ray pulses at LCLS are very similar, thereby validating the design concept. To the best of our knowledge, the LCLS detector application reported here is the first practical use of colossal magnetoresistive manganite bolometers.