Development of TlBr gamma-ray imaging array for the growth in semiconductor SPECT

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H03629
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Tohoku Institute of Technology
• Principal Investigator: Onodera Toshiyuki 東北工業大学, 工学部, 准教授 (10620916)
• Co-Investigator(Kenkyū-buntansha): 人見 啓太朗 東北大学, 工学研究科, 准教授 (60382660)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: TlBr / SPECT / 核医学 / ガンマ線検出器

Outline of Final Research Achievements

Press mold techniques has been studied for obtaining plate shape TlBr crystals used in gamma-ray detectors. The molded TlBr crystals consists of oriented domains and poly crystals. TlBr pixelated gamma-ray detectors with 1 mm x 1mm anodes were fabricated from molded TlBr crystals with 2 mm thick. Although the pixelated detectors exhibited no photoelectric peaks, the detectors obviously responded for irradiation of 662-keV gamma-rays from a Cs-137 source. These results mean that radiation detectors fabricated from molded TlBr crystals may useful for application of X-ray imaging detectors. Further works is necessary for development of techniques for preventing TlBr crystals sticking on punch plates after the mold process.

Free Research Field

ガンマ線検出器

Academic Significance and Societal Importance of the Research Achievements

TlBrは、ガンマ線のエネルギー弁別に優れる半導体の特長と高原子番号、高密度に由来する高い検出感度を併せ持つ新規の半導体材料である。本研究は、半導体材料として稀となるTlBrの可塑性の注目した新たな結晶製造技術の開発であった。本研究で試作したTlBr結晶は、ガンマ線検出器として十分な品質に及ばなかったが、X線イメージング等の応用など新たな展開先も見出すことができた。本研究で明らかとしたTlBrの品質を低下させる要因の解決を集中的に実行することでTlBrの特長を引き出し、当初の目標と設定した先端医療分野への応用に繋がると考えられる。