The present disclosure provides a highpurity germanium hpge detector, comprising. Ortec offers a broad range of semiconductor photon detectors and options, as can be seen in the figure, covering energies in a range from a few hundred ev to 10mev gamma ray and upper. A semiconductor detector in ionizing radiation detection physics is a device that uses a semiconductor usually silicon or germanium to measure the effect of incident charged particles or photons semiconductor detectors find broad application for radiation protection, gamma and xray spectrometry, and as particle detectors. High purity germanium detectors hpge detectors are the best solution for precise gamma and xray spectroscopy. The detector energy resolution follows a characteristic.
Some of the features that make silicon an excellent choice of material are the purity and the absence of dislocations, defects, and impurities. High purity germanium detector in gammaray spectrometry. Emerging role of highpurity germanium detectors for. Why high purity germanium hpge radiation detection technology is superior to other detector technologies for isotope identification synopsis. Resolution and efficiency of high purity germanium detector. This detector has been transported at room temperature, temperaturecycled many times to remove surface contamination, and remains an excellent device with a resolution of 4.
A highpurity germanium detector was modeled in mcnp6. For applications where temperature stability of response is important near the cutoff, thermoelectrically cooled detectors are available. Segmented planar high purity germanium detectors were developed. I have a question regarding gamma ray detector, the high purity germanium detector or aka hpge.
The impact of the procedure and geometry on the detector performance was analyzed for eight detectors. Germanium detectors germanium short form catalog in pdf format j16 series detectors are highquality germanium photodiodes designed for the 800 to 1800nm wavelength range. Highpurity germanium detectors hpge detectors are the best solution for precise gamma and xray spectroscopy. Germanium76 is one of a handful of isotopes that can only decay through double beta decay of those isotopes, it is the second lightest and the most plentiful as a semiconductor, germanium is already commonly used in detectors using the same material for both source and detector allows for very simple detector construction. In comparison to silicon detectors, germanium is much more efficient than silicon for radiation detection due to its atomic number being much higher than silicon and due to lower average energy necessary to create an electronhole. A prototype high purity germanium detector for high.
Introduction silicon semiconductor detectors described in the previous chapter have depletion depths less than 1 mm, which are sufficient for charged particle spectroscopy or soft xray detection. For photon spectroscopy in the energy region of hundred kev or several mev, much thicker semiconductor. As a result, the fabrication process of small planar detectors at usd is discussed in great detail. High purity germanium detector repair conference osti. Gamma background studies for the xenon experiment using a high purity germanium detector by jesse isaac angle may 2008 ci v. Signal modeling of highpurity ge detectors with a small read. Use of a highpurity germanium semiconductor detector for. The ultimate result of this analysis would be the deployment of this detector on an autonomous robot for sample collection and remote analysis.
The wvalue and energy resolution dependencies on the xray energy have been studied. These crystals should not have a net electrically active impurity concentration greater than 10 l0 cm. High purity germanium detector array spie digital library. Performance of bare highpurity germanium detectors in liquid argon for the gerda experiment m.
This summer student project involved the test and calibration of two high purity coaxial germanium gammaray detectors. Regardless of the superlative used, the detector is basically a cylinder of germanium with an ntype contact on the outer surface, and a ptype contact on the surface of an axial well. Fabrication process development for high purity germanium. What is meant by the detection efficiency at specific gammaray energy. It can be made in large volumes to detect high energies and when operating at cryogenic temperatures it has. Characterization of a highpurity germanium detector for. High purity germanium detector array, proceedings of spie. Performance of bare highpurity germanium detectors in. A highpurity berkeley germanium detector is in use at the argonne cp5 reactor. The purpose of this project was to develop a compact, modular multichannel xray detector with integrated electronics.
Detectors highpurity germanium detectors broad energy. Evaluation of a high purity germanium detector body. Performance of the ultrahigh rate germanium uhrge system. Germanium detectors are semiconductor diodes having a pin structure in which the intrinsic i region is sensitive to ionizing. Thus, the impurity concentration should be much reduced down to 1010. Fabrication process development for highpurity germanium. High purity germanium detector calibration at isolde. We present an initial evaluation of a mechanicallycooled, highpurity germanium doublesided strip detector as a potential gamma camera for smallanimal spect. The purpose of this research is to investigate the feasibility of using a high purity germanium double sided strip detector hpgedssd to image special nuclear material snm for use in the field of nuclear nonproliferation. The excellent energy resolution that hpge detectors afford often makes them the detector of choice for applications as diverse as nuclear physics research, medical imaging, homeland security, and environmental monitoring. As a result, the fabrication process of small planar detectors at usd was discussed in great detail. Ortec provides a comprehensive suite of hpge radiation detector solutions covering an extensive range of energies and for a variety of applications. This does not come better than in topsil high purity silicon hps. We use both ptype and ntype germanium and we use diffused, implanted, and barrier contacts to achieve this product variety.
International journal of applied radiation and isotopes, vol. The conventional coaxial germanium detector is often referred to as pure ge, hpge, intrinsic ge, or hyperpure ge. Germanium detectors are semiconductor diodes having a pin structure in which the intrinsic i region is sensitive to ionizing radiation, particularly x rays and gamma. Gamma background studies for the xenon experiment using a high purity germanium detector by jesse isaac angle may 2008 chair. The response of highpurity germanium detectors to xrays. Two types of geometry were used to fabricate hpge detectors. In this case, however, it is advantageous to choose germanium rather than silicon as the detector material. Index termsneutrinoless double beta decay, gerda, hpge detector, liquid argon. Thus, the impurity concentration should be much reduced down to.
Physics the xenon dark matter experiment, deploi 4 at the gran sasso national laboratory in italy on march 2006, is a liquid noble gas detector designed to directly detect dark matter. The germanium detector array, gerda, will search for neutrinoless double beta decay in 76ge at the national gran sasso laboratory of the infn. Bare highpurity germanium detectors enriched in 76ge will be submerged in liquid argon serving simultaneously as a shield against external radioactivity and as a cooling medium. If silicon or germanium of normal semiconductor purity is employed, the maximum achievable depletion depth is a few mm even at bias voltages close to the breakdown level. When photons interact with the material within the depleted volume of a detector, charge carriers holes and electrons are produced and are swept by the electric. Segmented highpurity germanium detectors springerlink. In gerda phasei, reprocessed enrichedge detectors, which were previously. What is high purity germanium detector hpge definition. This relatively high value is of practical concern since highpurity germanium hpge is often the detector of choice for a and xray spectrometry. This coaxial detector is available in an energy range of 10 kev to 10 mev. We measured full energy peak efficiency of highpurity germanium detector which is important for gammaray spectrometry experiments. Youngman, evaluation of a high purity germanium detector body monitor, radiation protection dosimetry, volume 53, issue 14, 1 may 1994.
Calibration of hpge gammaray planar detector system for. The detector array is suspended in a liquid argon cryostat lined with copper and surrounded by an ultrapure water tank. The experiment uses high purity enriched ge crystal diodes as a beta decay source and particle detector. Introduction gammaray spectrometry using high purity germanium hpge detectors has been an essential and principal corresponding author. This coaxial detector is available in an energy range of 40kev to 10 mev and offers high efficiency of radiation detection.
Calculation of the peak efficiency of highpurity germanium. Learn more about ortecs high purity germanium radiation detectors hpge today. Ssbi can offer the optimum detector for a wide range of applications. Comparison of a high purity germanium gamma ray spectrometer. Hpge detectors excel in gammaray spectroscopy, offering excellent energy resolution with large detector sizes for high radiation detection efficiency.
The high purity germanium spectroscopy detector is used in the detection and analysis of gammaray of environmental objects in nuclear energetics, products of industry and agriculture, medicine, etc. Keywords gammaray spectrometry, solid angle, efficiency, radioactive measurements 1. A semiconductor detector in ionizing radiation detection physics is a device that uses a semiconductor usually silicon or germanium to measure the effect of incident charged particles or photons. This coaxial detector is available in an energy range of 40kev to. High purity germanium remains the material of choice for the detection of photons in the range of mev or higher, down to the hard xray range. On the underground production of high purity germanium detectors. The resolution at low energies is equivalent to that of our low ener. We measured full energy peak efficiency of high purity germanium detector which is important for gammaray spectrometry experiments. Introduction t he germanium detector array, gerda, will search for neutrinoless double beta decay 0 in 76ge 1 with the goal to investigate the nature of neutrinos and their mass.
The electric and spectrometric characteristics of each individual segment and interactions between segments were investigated. High purity germanium detector calibration at isolde gu. For the nuclear hobbyist, an hpge opens a window into a fascinating realm of homeaccessible, lowintensity nuclear reactions that are obscured by background in other detectors lacking the superlative resolution. High purity germanium detectors are mostly used for gamma spectroscopy in nuclear physics, as well as xray spectroscopy. Fabrication and characterization of highpurity germanium. High purity germanium hpge is widely used xray and.
A prototype high purity germanium detector array designed for use in the pulse height analysis mode as a discrete photon energy detector for medical imaging was fabricated and tested. Digital timing algorithm for high purity germanium detectors. As a result, gammaray spectrometers based on highpurity germanium detectors are emerging as a powerful tool for a range of planetary science applications. Energy linearity of highpurity germanium detectors in the. The first triple cluster detector was successfully assembled for the next generation highresolution gammaray spectrometer. Highpurity germanium hpge detectors can be produced from germanium material enriched in 76ge, which serves simultaneously as a source and as detector medium. Highpurity germanium strip detectors possible applications to sr studies. Highpurity germanium for gamma detectors technical. Canberra models gc7020 old, from 1990, and gx6020 new, from. High purity germanium hpge detectors remain the recognized gold standard for highresolution gammaray spectroscopy. Characterization of mechanically cooled high purity. Characterization of mechanically cooled high purity germanium.
The germanium crystals used for the fabrication of nuclear radiation detectors are required to have a purity and crystalline perfection which is unsurpassed by any other solid material. Nats offers a complete range in high purity germanium detectors hpge. Digital timing algorithm for high purity germanium detectors knox andrew, university of massachusetts lowell, krzysztof starosta, david miller, constantin vaman, phillip voss, dirk weisshaar, michigan state universitynational superconduction cyclotron labratory the next generation of ray detector arrays will be composed of large volume high. Using this model and the source term, the predicted response spectrum for each fallout composition was generated and compared using genie spectroscopy software in an attempt to find differentiating features between them. No abrupt variation of wis observed at the germanium k absorptionedge 11. High purity germanium hpge radiation detectors are well established as a valuable tool in nuclear science, astrophysics, and nuclear security applications. High purity germanium detectors hpge are not just laboratory instruments anymore. The performance of the germanium ge detector body monitor that has been recently installed at nrpb chilton is evaluated and compared with the perfo. The detector type is high purity germanium, which is a semiconductor that must be temperature controlled with liquid nitrogen to 77 k due to excessive leakage current at higher temperatures 2. Gamma background studies for the xenon experiment using a. It is 90 mm in diameter and 10 mm thick with two sets of 16 orthogonal strips that have a 4.
Calculation of the peak efficiency of highpurity germanium detectors. The advantages of the intrinsic radiopurity and excellent spectroscopic performance 2 3 kev full width at half maximum resolution at qbb 2039 kev of hpge detectors have. With an atomic number of 32, germanium has a much higher photoelectric cross section than silicon atomic. Performance of bare highpurity germanium detectors in liquid. This work investigates the ability of a high purity germanium detector to perform postdetonation forensics on the debris from several types of nuclear weapons 24 hours after detonation. Characteristics of a highpurity germanium detector. Results obtained as a function of the photon input rate, energy resolution, and techniques for correcting for pulse overlap at high count rates will be discussed. High purity germanium spectroscopy system north american. Physics the xenon dark matter experiment, deployed at the gran sasso national laboratory in italy on march 2006, is a liquid noble gas detector designed to directly detect dark matter. Five things you need to know about using highpurity. Segmentation of pn junction was performed by implantation of boron for the ntype ge and mechanical grooving of the li diffusion. Abstractthe germanium detector array, gerda, will search for neutrinoless double beta decay in 76ge at the national gran sasso laboratory of the infn.
Computer modeling of highpurity germanium detectors in. Sep 21, 2011 we present an initial evaluation of a mechanicallycooled, high purity germanium doublesided strip detector as a potential gamma camera for smallanimal spect. This detector, based upon emerging silicon drift detector sdd technology, will be capable of high data rate operation superior to the current state of the art offered by high purity germanium hpge detectors, without the need for liquid nitrogen. Topsil hps float zone silicon for detectors has the following unique.
We use both ptype and ntype germanium and we use diffused, implanted, and. The response of a highpurity germanium detector to xrays in the 815kev energy region has been investigated. The detector consists of an ntype hpge crystal, 60mm in diameter and 90mm in length, with 36fold segmentation of the outer boron implanted contact. The following are five things you need to know about the use of hpge detector systems for homeland security applications in the field. Other articles where germanium detector is discussed. The canberra broad energy ge bege detector covers the energy range of 3 kev to 3 mev like no other.
Semiconductor detectors also can be used in gammaray spectroscopy. High purity germanium hpge is the only radiation detection technology that provides sufficient information to accurately and reliably identify radionuclides from their passive gamma ray emissions. Because germanium has relatively low band gap, these detectors must be cooled in order to reduce the thermal generation of charge carriers thus reverse leakage current to an acceptable level. A 128channel microstrip germanium detector system has been developed to efficiently detect comptonscattered xrays. Segmentation of pn junction was performed by implantation of boron for the ntype ge and mechanical grooving of the li diffusion layer for the ptype ge. Amorphous germanium age contacts are used for blocking both electrons and holes. Otherwise, leakage current induced noise destroys the energy resolution of the detector.
A brief but very effective description on the basic formation. Since the operation of hpgebased detectors is possible only at or below the liquid nitrogen temperature, their advantage is mainly the resolution, which matches the fano factor if appropriate cooled electronic readout is used. Digital gammaray spectroscopy with high purity germanium. To complete the gamma spectroscopy laboratory set caen sys includes in its offer a wide choice of high purity germanium detectors hpge. A high purity berkeley germanium detector is in use at the argonne cp5 reactor. Broad energy germanium detectors bege by canberra mirion technologies, inc. These detectors are made of high purity germanium hpge ptype and n, or silicon lithium sili. The invention discloses a high purity germanium detector, which comprises a high purity germanium crystal, a first electrode and a second electrode, and a conductive protection ring, wherein the high purity germanium crystal has an intrinsicregion exposed surface.
The ultra high rate germanium uhrge project goal was to develop technology to operate high purity germanium hpge detectors with high throughput 85% in environments with incoming gammaxray event rates r106 s. High purity germanium hpge radiation detectors products. The first gamma ray spectrometer is the one dimensional high purity germanium spectrometer. Sep 16, 2011 a high purity germanium hpge detector is the ultimate instrument for energy spectrometry of gamma radiation. Fabrication process development for highpurity germanium radiation detectors with amorphous semiconductor contacts by quinn looker doctor of philosophy in nuclear engineering university of california, berkeley professor kai vetter, chair highpurity germanium hpge radiation detectors are well established as a valuable tool in. Because the issue with leakage current only applies during operation, hpge. The detectors from the hdm and igex experiments were reprocessed and used in phase 1. Semiconductor detectors find broad application for radiation protection, gamma and xray spectrometry, and as particle detectors.
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