University of Missouri

Other

Kansas State University Research Foundation

Radiation Detection Technologies, Inc.

Steven Lawrence Bellinger

Douglas Scott McGregor

Ryan G Fronk

Anthony N Caruso

John K Shultis

William H Miller

Philip B Ugorowski

Thomas M Oakes

Eliot R Myers

Cory B Hoshor

Brian Cooper

Kyle Alan Nelson

Brent J Rogers

Walter J McNeil

William L Dunn

James Currie

Simon Bolding

Timothy J Sobering

Stephen M Young

Joseph A Crow

Anthony M Caruso

Alex Usenko

Martin F Ohmes

Bryan Willis

Blake B Rice

Clell J Solomon

Eric L Patterson

Benjamin William Montag

Logan Whitmore

Process flow for a stacked power diode and design of the resulting diode is disclosed. Blanket epitaxy over heavy doped wafers is performed. By controlling dopant addition during epitaxy, desired n-type, diode base, and p-type doping profiles and thicknesses achieved. V-groove pattern if formed on wafers by depositing mask film, lithography and anisotropic etch. Islands surrounded by V-grooves define individual diodes. V-grooves serve as side insulation. Next, oxidation step passivates V-grooves. Further, the mask film is stripped to open diode contact areas on both sides of wafers. Next high melting point metal and low melting point metal films are selectively electroplated on all open silicon surfaces. Stacking is performed on wafer level by bonding of desired wafer count by solid-liquid interdiffusion process. Wafer stacks are sawed into individual stacked diode dies along outer slopes of V-grooves. Final stacked devices can be used as DSRD—drift step recovery diodes. Compared to DSRDs made by known methods, better fabrication yield and higher pulse power electrical performance is achieved.

Stacked diode with side passivation and method of making the same

A method of producing a four-layer silicon diode, including selecting a first silicon wafer, wherein said first silicon wafer is CZ-grown B-doped with <100> orientation, a resistivity of less than 0.01 Ohm-cm, and an oxygen content of greater than 10 ppma, and then selecting a second silicon wafer, wherein said second silicon wafer is CZ-grown P-doped with <100> orientation, a resistivity of less than 0.005 Ohm-cm, and an oxygen content of greater than 10 ppma, followed by cleaning the respective first and second silicon wafers. The wafers are then HF treated to yield respective first and second cleaned wafers, the first cleaned wafer is positioned into a first furnace and the second cleaned wafer is positioned into a second furnace, wherein the first and second furnaces are not unitary. Next is annealing the respective first and second cleaned wafers in a reducing atmosphere to yield respective first and second respective out-diffused gradient wafers, followed by bonding together respective first and second heat-treated wafers to yield a mated and/or bonded four-layer substrate having a first heavy doped n-type layer, a second gradient doped n-type layer, a third gradient doped p-type layer, and a fourth heavy doped p-type layer.

Diode and method of making the same

A system and method for making a neutron detector includes stacking anode frames and laminated frames to form a detector insert. The laminated frames are formed by laminating a foil of neutron-responsive material to an aluminum frame plated with a metal that does not react with the neutron-responsive material. The anode frames include an anode wire tensioned to a predetermined tension. The anode wires are electrically coupled to a top lid that includes an electrical connector and a gas feed through. The top lid is pressed into a tank with the detector insert.

Methods for manufacturing lithium foil neutron detectors

A semiconductor neutron detector and a semiconductor process is provided to manufacture a semiconductor neutron detector. First, a substrate with flat surface having a dielectric layer is formed thereon is provided. Thereafter, a masking pattern is applied and etched into the dielectric layer to expose semiconductor features on opposite sides of the substrate. The semiconductor substrate is submerged into an etchant composed of a semiconductor etching solution to etch deep cavities into the substrate in the exposed regions. Afterwards, dopant impurities are introduced and are driven into the semiconductor, under high temperature, into opposite sides of the etched features to produce one or more rectifying junctions. Afterwards, LiF and/or B particles are forced into the cavities through high velocity methods.

High-efficiency microstructured semiconductor neutron detectors and process to fabricate high-efficiency microstructured semiconductor neutron detectors

A neutron detection apparatus includes a neutron detector and an analyzer. The neutron detector includes a plurality of neutron detector assemblies, where each of the neutron detector assemblies includes a plurality of neutron detection devices. The neutron detector also includes a moderating volume. The plurality of neutron detector assemblies are disposed within the moderating volume so as to form a three-dimensional array of neutron detection devices within the moderating volume. The analyzer is communicatively coupled to each of the neutron detection devices of the plurality of neutron detector assemblies. The analyzer configured to receive one or more measured response signals from each of the neutron detection devices, and perform one or more analysis procedures to determine one or more characteristics associated with the one or more neutron sources based at least on the received one or more measured response signals.

Apparatus and method for the determination of one or more neutron source characteristics

Gas-filled neutron detectors, an imaging system and an array of such detectors are provided. Surfaces or surface portions incorporated into the gas-filled neutron detectors are coated with and/or composed of at least partially, neutron reactive material. The surfaces may be flat or curved, fins or plates, foils, thin sheets, porous or filamentary material, or semi-solid material or aerogel. The incorporation of the extended surfaces coated with or composed of neutron reactive material increases the neutron detection efficiency of the gas-filled detectors. The surfaces can be made of conductive, semiconductive, semi-insulating, or insulative materials. The surfaces are arranged such that they do not detrimentally detract from the main function of a gas-filled detector with particular attention to gas-filled proportional detectors. The surfaces may be arranged in the detectors to allow for modular construction. The surfaces are designed and arranged such that more than a single reaction product may escape the surface.

Gas-filled neutron detectors and imaging system and array of such detectors

A neutron detection system may include a neutron detector including a plurality of neutron detection devices, a plurality of discrete neutron moderating elements, wherein each of the neutron moderating elements is disposed between two or more neutron detection devices, the plurality of neutron detection devices and the plurality of discrete neutron moderating elements disposed along a common axis, a control system configured to generate a detector response library, wherein the detector response library includes one or more sets of data indicative of a response of the detector to a known neutron source, receive one or more measured neutron response signals from each of the neutron devices, the one or more measured response signals response to a detected neutron event, and determine one or more characteristics of neutrons emanating from a measured neutron source by comparing the one or more measured neutron response signals to the detector response library.

Apparatus and method for determination of one or more free neutron characteristics

A neutron detection system includes a plurality of neutron detector assemblies, the neutron detector assemblies including a plurality of neutron detection devices, wherein the neutron detection devices are configured to detect one or more characteristics of neutrons emanating from one or more neutron sources and impinging on one or more neutron detection devices; a plurality of discrete moderating elements, wherein each of the discrete moderating elements is disposed proximate to at least one neutron detector assembly, the plurality of neutron detector assemblies and the plurality of discrete moderating elements disposed along a common axis, wherein the discrete moderating elements are configured to moderate the energy of neutrons impinging on one or more of the neutron-photon detector assemblies; and a control system configured to: determine one or more characteristics associated with the one or more neutron sources based on the received one or more measured response signals.

A method of making a neutron detector such as a microstructured semiconductor neutron detector is provided. The method includes the step of providing a particle-detecting substrate having a surface and a plurality of cavities extending into the substrate from the surface. The method also includes filling the plurality of cavities with a neutron-responsive material. The step of filling including the step of centrifuging nanoparticles of the neutron-responsive material with the substrate for a time and a rotational velocity sufficient to backfill the cavities with the nanoparticles. The material is responsive to neutrons absorbed, thereby, for releasing ionizing radiation reaction products.

Method of fabricating a neutron detector such as a microstructured semiconductor neutron detector

Surfaces or surface portions incorporated into gas-filled neutron detectors are coated with and/or composed of at least partially, neutron reactive material. The surfaces may be flat or curved fins or plates, foils, porous or filamentary material, or semi-solid material or aerogel. The incorporation of the extended surfaces coated with or composed of neutron reactive material increases the neutron detection efficiency of the gas-filled detectors over conventional coated designs. These surfaces or surface portions increase the amount of neutron reactive material present in the detector over conventional coated designs and, as a result, increase the neutron detection efficiency. The surfaces can be made of conductive, semiconductive or insulative materials. The surfaces are arranged such that they do not detrimentally detract from the main function of a gas-filled detector with particular attention to gas-filled proportional detectors.

Gas-filled neutron detectors having improved detection efficiency

Non-streaming high-efficiency perforated semiconductor neutron detectors, method of making same and measuring wands and detector modules utilizing same are disclosed. The detectors have improved mechanical structure, flattened angular detector responses, and reduced leakage current. A plurality of such detectors can be assembled into imaging arrays, and can be used for neutron radiography, remote neutron sensing, cold neutron imaging, SNM monitoring, and various other applications.

Non-streaming high-efficiency perforated semiconductor neutron detectors, methods of making same and measuring wand and detector modules utilizing same

Growing community of inventors

Manhattan, KS, United States of America

Steven Lawrence Bellinger