Dual-side etched microstructured semiconductor neutron detectors
dc.contributor.author | Fronk, Ryan G. | |
dc.date.accessioned | 2017-04-19T16:33:20Z | |
dc.date.available | 2017-04-19T16:33:20Z | |
dc.date.graduationmonth | May | en_US |
dc.date.issued | 2017-05-01 | en_US |
dc.date.published | 2017 | en_US |
dc.description.abstract | Interest in high-efficiency replacements for thin-film-coated thermal neutron detectors led to the development of single-sided microstructured semiconductor neutron detectors (MSNDs). MSNDs are designed with micro-sized trench structures that are etched into a vertically-oriented pvn-junction diode, and backfilled with a neutron converting material, such as ⁶LiF. Neutrons absorbed by the converting material produce a pair of charged-particle reaction products that can be measured by the diode substrate. MSNDs have higher neutron-absorption and reaction-product counting efficiencies than their thin-film-coated counterparts, resulting in up to a 10x increase in intrinsic thermal neutron detection efficiency. The detection efficiency for a single-sided MSND is reduced by neutron streaming paths between the conversion-material filled regions that consequently allow neutrons to pass undetected through the detector. Previously, the highest reported intrinsic thermal neutron detection efficiency for a single MSND was approximately 30%. Methods for double-stacking and aligning MSNDs to reduce neutron streaming produced devices with an intrinsic thermal neutron detection efficiency of 42%. Presented here is a new type of MSND that features a complementary second set of trenches that are etched into the back-side of the detector substrate. These dual-sided microstructured semiconductor neutron detectors (DS-MSNDs) have the ability to absorb and detect neutrons that stream through the front-side, effectively doubling the detection efficiency of a single-sided device. DS-MSND sensors are theoretically capable of achieving greater than 80% intrinsic thermal neutron detection efficiency for a 1-mm thick device. Prototype DS-MSNDs with diffused pvp-junction operated at 0-V applied bias have achieved 53.54±0.61%, exceeding that of the single-sided MSNDs and double-stacked MSNDs to represent a new record for detection efficiency for such solid-state devices. | en_US |
dc.description.advisor | Douglas S. McGregor | en_US |
dc.description.degree | Doctor of Philosophy | en_US |
dc.description.department | Department of Mechanical and Nuclear Engineering | en_US |
dc.description.level | Doctoral | en_US |
dc.description.sponsorship | Defense Threat Reduction Technologies | en_US |
dc.identifier.uri | http://hdl.handle.net/2097/35426 | |
dc.language.iso | en_US | en_US |
dc.publisher | Kansas State University | en |
dc.subject | Neutron | en_US |
dc.subject | Radiation | en_US |
dc.subject | Neutron detection | en_US |
dc.subject | Radiation detection | en_US |
dc.title | Dual-side etched microstructured semiconductor neutron detectors | en_US |
dc.type | Dissertation | en_US |