Time-of-flight neutron detection using PECVD grown boron carbide diode detector

Nina Hong, L. Crow, S. Adenwalla

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

The development of novel neutron detectors requires an understanding of the entire neutron detection process, a process which depends strongly on material properties. Here we present accurate measurements of the neutron detection efficiency of an unenriched 640 nm thick boron carbide solid state neutron detector grown by plasma enhanced chemical vapor deposition as a function of the neutron wavelength at a time-of-flight facility. The data were compared to that obtained simultaneously by a calibrated nitrogen detector over the same wavelength range. The measured spectra of both detectors fit a Maxwell-Boltzmann wavelength distribution, thereby indicating that the boron carbide detector can be used as a reliable beam monitor. Measurements of the material properties (density, thickness and elemental composition) of the semiconducting boron carbide enable a precise calculation of the ideal expected neutron detection efficiency. The calculated neutron detection efficiency for the effective moderator temperature (obtained from a fit to the Maxwell-Boltzmann distribution) showed excellent agreement with the experimentally determined neutron detection efficiency of 1.25%. Higher efficiencies may be obtained either by increased film thickness and/or 100% 10B enrichment of the boron carbide source molecule.

Funding

The support of NSF through grant NSF-0725881 is gratefully acknowledged. The work at ORNL has been sponsored by t he Basic Energy Science (BES) Program, Office of Science, U.S. Department of Energy under contract number DE-AC05-00OR22725 with UT-Battelle, LLC. We thank Dr. Ravi Billa for his XRR experiments and data analysis.

Keywords

  • Boron carbide
  • Neutron detection
  • Plasma enhanced chemical vapor deposition
  • Solid state neutron detector
  • Time of flight neutron detection

Fingerprint

Dive into the research topics of 'Time-of-flight neutron detection using PECVD grown boron carbide diode detector'. Together they form a unique fingerprint.

Cite this