SCINTILLATOR CRYSTAL AND RADIATION DETECTOR

• US 20080067391A1
• Filed: 09/20/2007
• Published: 03/20/2008
• Est. Priority Date: 09/20/2006
• Status: Active Grant

• Current Assignee: Oxide Corporation
• Original Assignee: Hitachi Chemical Company Limited (Resonac Holdings Corp.)
• Inventors: SUMIYA, Keiji, AOSHIMA, Masahiro, SHIMIZU, Shigenori, ISHIBASHI, Hiroyuki, NACHIMUTHU, Senguttuvan
• Granted Patent: US 7,692,153 B2
• Time in Patent Office: Days
• US Class Current: 250/361R
• CPC Class Codes: C01F 17/253 Halides
• CPC Class Codes: C01P 2002/52 containing elements as dopants
• CPC Class Codes: C01P 2002/54 one element only
• CPC Class Codes: C01P 2002/80 defined by measured data other than those specified in group C01P2002/70
• CPC Class Codes: C09K 11/7719 Halogenides C09K11/7716 takes precedence
• CPC Class Codes: C09K 11/7772 Halogenides C09K11/7767 takes precedence
• CPC Class Codes: C30B 11/00 Single-crystal growth by normal freezing or freezing under temperature gradient, e.g. Bridgman-Stockbarger method C30B13/00, C30B15/00, C30B17/00, C30B19/00 take precedence; under a protective fluid C30B27/00
• CPC Class Codes: C30B 29/12 Halides
• CPC Class Codes: G01T 1/2023 Selection of materials see provisionally also G01T1/202

Abstract

A scintillator crystal represented by the following general formula (1).

Ln_(1−y)Ce_yX₃:M   (1)

wherein Ln_(1−y)Ce_yX₃ represents the chemical composition of the matrix material, Ln represents one or more elements selected from the group consisting of rare earth elements, X represents one or more elements selected from the group consisting of halogen elements, M is the constituent element of the dopant which is doped in the matrix material and represents one or more elements selected from the group consisting of Li, Na, K, Rb, Cs, Al, Zn, Ga, Be, Mg, Ca, Sr, Ba, Sc, Ge, Ti, V, Cu, Nb, Cr, Mn, Fe, Co, Ni, Mo, Ru, Rh, Pb, Ag, Cd, In, Sn, Sb, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl and Bi, and y represents a numerical value satisfying the condition represented by the following inequality (A):

0.0001≦y≦1.   (A)

Claims

1. A scintillator crystal represented by the following general formula (1).

Ln₍₁₋

y)Ce_yX₃;

M 

 

(1)

wherein Ln<sub>(1−

y)</sub>Ce_yX₃ represents the chemical composition of the matrix material, Ln represents one or more elements selected from the group consisting of rare earth elements, X represents one or more elements selected from the group consisting of halogen elements, M is the constituent element of the dopant which is doped in the matrix material and represents one or more elements selected from the group consisting of Li, Na, K, Rb, Cs, Al, Zn, Ga, Be, Mg, Ca, Sr, Ba, Sc, Ge, Ti, V, Cu, Nb, Cr, Mn, Fe, Co, Ni, Mo, Ru, Rh, Pb, Ag, Cd, In, Sn, Sb, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl and Bi, and y represents a numerical value satisfying the condition represented by the following inequality (A);

0.0001≦

y≦

1 

 

(A).

2. A scintillator crystal according to claim 1, wherein Ln is La.

3. A scintillator crystal according to claim 1, wherein X is Br.

4. A scintillator crystal according to claim 1, wherein M is present at 0.0001-0.05% by weight with respect to the total weight of the scintillator crystal.

5. A scintillator crystal according to claim 1, wherein the fluorescence intensity distribution for the wavelength of the emitted fluorescence has two maximum values, and of these maximum values, the value of the fluorescence intensity for the maximum value at the short wavelength end divided by the fluorescence intensity for the maximum value at the long wavelength end is greater than 0.7.

6. A scintillator crystal according to claim 1, which is a single crystal.

7. A radiation detector comprising a photomultiplier tube and a scintillator provided with a scintillator crystal according to claim 1 formed on the outer photoelectric surface of the photomultiplier tube.

8. A radiation detector according to claim 7, which is incorporated in a positron emission tomography apparatus.