GROWTH OF LUTETIUM PHOSPHATE SCINTILLATOR CRYSTALS FOR POSITRON EMISSION TOMOGRAPHY

POSITRON EMISSION TOMOGRAPHY (PET) IS A POWERFUL NEW TOOL FOR RADIOGRAPHIC IMAGING OF HUMAN ORGANS, PARTICULARLY THE BRAIN. HOWEVER, MOST PRESENTLY KNOWN SCINTILLATOR MATERIALS FIND THEIR APPLICATION LIMITED BY DEFICIENCIES IN ONE OR MORE OF THE DESIRED CHARACTERISTICS: BRIGHTNESS, STOPPING POWER, SPEED, CHEMICAL STABILITY, AND COST. THUS, THE FULL REALIZATION OF THE POTENTIAL OF THIS DIAGNOSTIC TOOL REQUIRES THE DEVELOPMENT OF INNOVATIVE SCINTILLATOR MATERIALS THAT ARE FASTER, BRIGHTER, AND MORE SENSITIVE THAN ANY THAT ARE PRESENTLY AVAILABLE. A NEW MATERIAL SYSTEM WITH GREAT PROMISE AS A SCINTILLATION DETECTOR FOR PET APPLICATIONS HAS BEEN DISCOVERED. THIS MATERIAL, CERIUM-DOPED LUTETIUM PHOSPHATE, OFFERS A SUBSTANTIAL IMPROVEMENT IN PERFORMANCE OVER THOSE NOW BEING USED. IT HAS HIGH STOPPING POWER, SUPERIOR LIGHT OUTPUT, AND RAPID DECAY. INDEED, IT IS UNIQUE AMONG CURRENTLY KNOWN MATERIALS IN COMBINING SUPERIOR PERFORMANCE IN ALL IMPORTANT ASPECTS FOR SUCH APPLICATION. DESPITE ALL THESE ESTABLISHED ADVANTAGES, HOWEVER, ONE MAJOR DEVELOPMENT REMAINS TO BE ACHIVED BEFORE THEY CAN FULFILL THEIR DESTINED ROLE: A COMMERCIALLY VIABLE METHOD FOR FABRICATION. IN PHASE I THE FEASIBILITY OF APPLYING EITHER OF TWO RECOGNIZED TECHNOLOGIES, CZOCHRALSKI GROWTH FROM THE MELT AND TRAVELING ZONE FLUX GROWTH, TO THE PRACTICAL FABRICATION OF THE REQUISITE CRYSTALS WILL BE ASSESSED. SUITABLE SPECIMENS WILL THEN BE EVALUATED OPTICALLY, A FABRICATION METHOD OF CHOICE IDENTIFIED, AND THE GROUNDWORK LAID FOR FULL-SCALE EXPLOITATION IN PHASE II.