Purification and preparation of TlBr crystals for room temperature radiation detector applications

Oliveira, I.B.; Costa, F.E.; Chubaci, J.F.D.; Hamada, M.M.

doi:10.1109/tns.2004.829383

Cited by 45 publications

(51 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…There is agreement in the literature on the difficulty in growing crystals with high crystallographic perfection, high chemical purity and good stoichiometry and surface morphology, suitable to be used as room temperature semiconductor detectors [Oliveira et al, 2004, Marcondes et al, 2011. The role of the crystal impurities on the electrical properties and surface morphology of HgI 2 is crucial, and the performance of these detectors has been limited by the crystals quality.…”

Section: Introductionmentioning

confidence: 97%

“…Most of semiconductor crystals, such as PbI 2 (405°C) (Oliveira, et al, 2002), TlBr (468°C) (Oliveira et al, 2004 and BiI 3 (408.6°C) are purified and grown by the fusion technique However, the HgI 2 undergoes structural phase transition below its melting point (259°C), what makes its growth by fusion technique more difficult (Zhou et al. 2003;Martins et al 2012).…”

Section: Introductionmentioning

confidence: 99%

“…Carrier lifetime, mobility and the atomic number of the material used for radiation detectors represent intrinsic parameters, while extrinsic factors such as crystallographic perfection, surface morphology and stoichiometry and impurity levels can also play a major role in the performance of radiation detectors (Goorsky et al, 1996, Oliveira 2004). …”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Optimization of the HgI2 Crystal Preparation for Application as a Radiation Semiconductor Detector

Martins¹,

Santos²,

Ferraz³

et al. 2018

SET

View full text Add to dashboard Cite

The effect of HgI 2 crystal encapsulation using different polymer resins, with the intent of avoiding the oxidation of the crystal surface, was evaluated in this work. The crystal was purified and grown by the physical vapor transport (PVT) technique modified. Systematic measurements were carried out for evaluating the stoichiometry, structure orientation, surface morphology and impurity of the crystal grown. The purer region of the crystal grown was selected to be prepared as a radiation detector, applying water-based conductive ink contacts and copper wire on the crystal surfaces. After that, the crystal was encapsulated with a polymeric resin which insulates atmospheric gases, aiming to improve the stability of the HgI 2 detector. Four resins were used for crystal encapslation and the performance of the detector depended on the composition of the resins used. Among the four resins studied to evaluate the influence of encapsulation on the performance of crystals, as a radiation detector, the best result of resistivity and energy spectrum was obtained for the resin #3 (50% -100% of Methylacetate and 5% -10% of n-butylacetate). The encapsulation of crystals with polymer resins, performed with the intent of avoiding the oxidation of the crystal surface, did not compromise the measurements and were fully capable of detecting the presence of gamma radiation. The stability of the encapsulated HgI2 crystal detector was of up to 78 hs, while the stability found for HgI 2 detector no encapsulated was in order 3 ~4 hs.

show abstract

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Optimization of the HgI2 Crystal Preparation for Application as a Radiation Semiconductor Detector

Martins¹,

Santos²,

Ferraz³

et al. 2018

SET

View full text Add to dashboard Cite

show abstract

“…This type of detector has a large applicability as X ray and gamma ray spectrometer, operating at room temperature (McGregor & Hermon, 1997;Martins et al, 2012;Oliveira et al, 2004). Layered semiconductor materials have a number of properties that make them attractive for such application.…”

Section: Introductionmentioning

confidence: 99%

“…However, the common factor among the semiconductor materials to operate as room temperature semiconductor radiation detectors is their difficulty to obtain crystals with high purity, high crystallographic perfection and good chemical stoichiometry. It is know that the role of the impurities is crucial to grow crystals with these required characteristics, thus, improvements on the chemical purification and the impurity reduction analysis should be achieved Oliveira et al, 2004).…”

Section: Introductionmentioning

confidence: 99%

Purification and Crystal Growth of the Bismuth (III) Iodide-influence of Trace Impurities on the Crystal Quality

Ferraz¹,

Armelin²,

Oliveira³

et al. 2017

SET

View full text Add to dashboard Cite

This work describes the experimental procedure of purification and preparation of BiI 3 crystals by Repeated Vertical Bridgman technique, aiming a future application of this semiconductor crystal as a room temperature radiation detector. The BiI 3 powder used as raw material was purified three times and, at each purification, the crystal was evaluated by systematic measurements of the reduction of the impurities, crystalline structure, stoichiometry and surface morphology. The reduction of the trace metal impurities in the BiI 3 , at each purification, was analyzed by Instrumental Neutron Activation Analysis (INAA), in order to evaluate the efficiency of the purification technique established in this work. It was demonstrated that the Repeated Bridgman technique is effective to reduce the concentration of many impurities in BiI 3 , such as Ag, As, Br, Cr, K, Mo, Na and Sb. The crystalline structure of the BiI 3 crystal purified twice and three times was similar to BiI 3 pattern. However, for BiI 3 powder and purified once, an intensity contribution of the BiOI was observed in the diffractograms. Improvement in the stoichiometric ratio was observed at each purification step, as well as the crystal surface morphology.

show abstract

Purification and crystal growth of TlBr for application as a radiation detector

Oliveira¹,

Chubaci²,

Armelin

et al. 2004

Cryst. Res. Technol.

View full text Add to dashboard Cite

Thallium bromide is a semiconductor compound with high atomic number and density. It has a CsCl-type simple cubic crystal structure and it is non-hygroscopics. The TlBr crystals are relatively soft with a knoop hardness number of 12. In this work, the TlBr commercial powder was purified by zone refining and the purest material section was used for crystal growth by Bridgman method. Efforts have been concentrated on the purification of the TlBr. The purification efficiency has been evaluated (NAA and ICP-MS) by impurities reduction results after zone refining passes. The crystalline quality was evaluated by X-ray diffraction. The characterized TlBr crystal as a detector has shown good response to gamma radiation.

show abstract

Purification and preparation of TlBr crystals for room temperature radiation detector applications

Cited by 45 publications

References 13 publications

Optimization of the HgI2 Crystal Preparation for Application as a Radiation Semiconductor Detector

Optimization of the HgI2 Crystal Preparation for Application as a Radiation Semiconductor Detector

Purification and Crystal Growth of the Bismuth (III) Iodide-influence of Trace Impurities on the Crystal Quality

Purification and crystal growth of TlBr for application as a radiation detector

Contact Info

Product

Resources

About