Semiconducting boron-rich neutron detectors

Abstract

Semiconducting boron-rich boron-carbon alloys have been deposited by plasma-enhanced chemical vapor deposition. Heterojunction diodes made with 276nm thick nanocrystalline layers of these alloys have been used as real-time solidstate neutron detectors. Individual neutrons were detected and signals induced by gamma rays were determined to be insignificant. Linearity of detection was demonstrated over more than two orders of magnitude in flux. The neutron detection performance was unaffected by > 1 x 10 15 neutrons / cm 2 . The source gas closo-1,2-dicarbadodecaborane (ortho-carborane) was used to fabricate the boron carbon alloys with only the natural isotopic abundance of 10 B. Devices made of thicker boron carbon alloy layers enriched in 10 B could lead to increased detection efficiency.

Increased drift carrier lifetime in semiconducting boron carbides deposited by plasma enhanced chemical vapor deposition from carboranes and benzene

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] Recent work has shown that neutron detectors and neutron voltaic devices, based on semiconducting boron carbides, may improve with some radiation exposure and are robust against radiation induced device degradation and failure. 14 The main causes for the poor neutron detection device performance are as follows: the insufficiently thick depletion region of the device, the need for a thicker device to come closer to neutron opacity, 1 and the need for better charge collection while maintaining low reverse bias leakage currents.…”

The coadsorption and interaction of molecular icosahedra with mercury

“…Semiconducting boron car bide represents a new class of semi conducting materials with potential ap plications in neutron detection and ra dioactive decay calorimetry [1][2][3][4][5]. Neu tron detectors with boron carbide have begun to attract attention [7][8][9].…”

The all boron carbide diode neutron detector: Comparison with theory

“…The small number of counts, after placing the Cd foil in position may also be the result of unsuccessfully moderated non-thermal neutrons for the PuBe source. The boron carbide heterojunctions diodes were also found to be insensitive to a 60 Co gamma source [1,2].…”

“…Semiconducting boron carbide represents a new class of semiconducting materials with potential applications in neutron detection and radioactive decay calorimetry [1][2][3][4][5][6][7]. Boron carbide thin fi lm diodes and devices have begun to attract attention as potentially highly effi cient solid state neutron detectors [8][9][10].…”

“…A number of boron based conversion layer neutron detector diode devices have been fabricated [5,12,[16][17][18][19][20][21][22][23][24], as well as some heterojunction diode detectors [1][2][3]5]. Both the heterojunction diodes (where one side of the diode, usually the p-layer, contains boron) and conversion layer devices have pulse height spectra characteristic of strong contributions from 0.…”