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dc.rights.licenseRestricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.
dc.contributorBhat, Ishwara B.
dc.contributorDahal, Rajendra
dc.contributorDanon, Yaron
dc.contributorDutta, Partha S.
dc.contributorLu, James
dc.contributor.authorHuang, Kuan-Chih (Jacky)
dc.date.accessioned2021-11-03T08:14:46Z
dc.date.available2021-11-03T08:14:46Z
dc.date.created2014-10-08T11:30:00Z
dc.date.issued2014-08
dc.identifier.urihttps://hdl.handle.net/20.500.13015/1219
dc.descriptionAugust 2014
dc.descriptionSchool of Engineering
dc.description.abstractSince neutrons are a very specific indicator of special nuclear materials (SNM), high efficiency neutron detectors are needed for the detection of illicit SNM at seaports, airports and border crossings. Besides, neutron detectors are useful for a wide variety of applications including homeland security, nuclear safeguards and process monitoring. For these applications, detectors with low bias voltages are advantageous. Detectors with compact and large detection areas are both desirable for different applications. Solid-state neutron detectors are better suited in many field applications than the existing gas filled tube neutron detectors because the latter has plenty of drawbacks, such as bulkiness, high bias voltage and high pressure requirement and high cost.
dc.description.abstractFollowing the achievement of an extremely low leakage current and a high thermal neutron detection efficiency, scalable large-area neutron detectors with detection areas up to 16 cm2 that require only a single preamplifier for data acquisition were fabricated and characterized. The relative efficiency remains almost the same when scaling the detector area from 1 cm2 up to 8 cm2 by connecting 1 cm2 detector modules in series. However, it decreases to 0.89 and 0.82, respectively, for 12 and 16 cm2. These measurements were obtained under zero bias voltage using a moderated 252Cf source. These results demonstrate the promise of using 10B filled micro-structured Si diodes as a cost-effective alternative to the 3He based neutron detection technology and the potential of fabricating scalable large-area solid-state neutron detectors that are desirable for many applications.
dc.description.abstractAs a part of boron deposition process, a continuous p+-n junction is formed by diffusing the initial portion of the boron deposition into the honeycomb structure in the same LPCVD reactor. Optimized diffusion temperature and diffusion time were obtained using TSUPREM-4 simulations and current-voltage (I-V) characteristics. A very low leakage current density of ~6×10-9 A/cm2 at -1 V was measured for the best 2.5×2.5 mm2 honeycomb-structured neutron detector with a continuous p+-n junction. A Maxwellian average thermal neutron detection efficiency of up to 26% was measured under zero bias voltage for the best 2.5×2.5 mm2 enriched boron filled honeycomb-structured neutron detector. These results are very encouraging for the fabrication of large-area solid-state neutron detectors that could be a viable alternative to 3He tube based technology.
dc.description.abstractA multiple deposition and etching process has been developed to facilitate the boron filling process in high aspect ratio honeycomb holes. The boron deposition process is carried out using low-pressure chemical vapor deposition (LPCVD) and the boron etching process is conducted using inductively coupled plasma reactive ion etching (ICP-RIE). Following the boron deposition process, the subsequent boron etching process removes the boron capping at the hole mouths prior to filling the holes with more 10B in order to minimize the size of the void inside the hole. As a result, boron fill factor after the second boron deposition has been enhanced up to 93% from 72%.
dc.description.abstractIn this research, a new type of detector structure was proposed, designed and fabricated. Among several detector structures evaluated, a honeycomb-like micro- structured Si p+-n diode that is filled with 10B as a neutron converter material was selected. A continuous p+-n junction is formed over the entire surface of the honeycomb structure in order to detect the energetic charged particles (alpha particles and 7Li ions) emitted from boron and thermal neutron interactions. The continuous p+-n junction reduces the interface traps from the etched Si surfaces, which minimizes the signal loss and lowers the leakage current simultaneously. At the same time, it also fully depletes the Si between the deep holes, which maximizes the signal voltage due the reduced device capacitance and enables the operation of the detectors without bias.
dc.language.isoENG
dc.publisherRensselaer Polytechnic Institute, Troy, NY
dc.relation.ispartofRensselaer Theses and Dissertations Online Collection
dc.subjectElectrical engineering
dc.titleFabrication and characterization of a novel self-powered solid-state neutron detector
dc.typeElectronic thesis
dc.typeThesis
dc.digitool.pid173088
dc.digitool.pid173089
dc.digitool.pid173090
dc.rights.holderThis electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.
dc.description.degreePhD
dc.relation.departmentDept. of Electrical, Computer, and Systems Engineering


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