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A bipolar-transistor-based sensor technique has been used to compare silicon displacement damage from known and unknown neutron energy spectra generated in nuclear reactor and high-energy-density physics environments. The technique has been shown to yield 1-MeV(Si) equivalent neutron fluence measurements comparable to traditional neutron activation dosimetry. This paper significantly extends previous results by evaluating three types of bipolar devices utilized as displacement damage sensors at a nuclear research reactor and at a Pelletron particle accelerator. Ionizing dose effects are compensated for via comparisons with 10-keV X-ray and/or cobalt-60 gamma ray irradiations. Nonionizing energy loss calculations adequately approximate the correlations between particle and device responses and provide evidence for the use of one particle type to screen the sensitivity of the other. [ABSTRACT FROM PUBLISHER]

The capability to characterize the neutron energy spectrum and fluence received by a test object is crucial to understanding the damage effects observed in electronic components. For nuclear research reactors and high energy density physics facilities this can pose exceptional challenges, especially with low level neutron fluences. An ASTM test method for characterizing neutron environments utilizes the 2N2222A transistor as a 1-MeV equivalent neutron fluence sensor and is applicable for environments with 1 \times 10^12 - 1 \times 10^14\,\,1 -MeV(Si)-Eqv.-n/cm2. In this work we seek to extend the range of this test method to lower fluence environments utilizing the 2N1486 transistor. The 2N1486 is shown to be an effective neutron displacement damage sensor as low as 1 \times 10^10\,\,1 -MeV(Si)-Eqv.-n/cm2. [ABSTRACT FROM PUBLISHER]