TRANSPARENT CERAMIC SCINTILLATION DETECTOR WITH GARNET STRUCTURE FOR POSITRON EMISSION TOMOGRAPHY Russian patent published in 2025 - IPC C09K11/78 C09K11/80 C04B35/01 C04B35/505 C04B35/626 G01T1/20 

FIELD: chemistry.

SUBSTANCE: invention can be used in making radiation detection systems for computed tomography (CT), positron emission tomography (PET) or single-photon emission computed tomography (SPECT). First, a powder containing a composition of formula: (Gd_3-a-cY_a)_x(Ga_5-bAl_b)_yO₁₂D_cB, where D is an activating alloying additive, which is selected from Tl⁺, Cu⁺, Ag⁺, Au⁺, Pb²⁺, Bi³⁺, In⁺, Sn²⁺, Sb³⁺, Ce⁴⁺, Eu²⁺, Yb²⁺, Nb⁵⁺, Ta⁵⁺, W⁶⁺ and combinations thereof; B is a heterovalent dopant selected from Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺, B³⁺ and combinations thereof; about 0.05–2; b about 1-3; x about 2.8–3.2; at about 4.8–5.2; s about 0.003–0.3. Powder can be formed by flame-aerosol pyrolysis of liquid precursor materials, by synthesis during combustion, by precipitation of particles from one or more liquid solutions by changing pH or by synthesis based on sol-gel technology. Optically transparent ceramics is formed by combining the powder in an oxidative atmosphere to reduce oxygen-related and/or thermodynamically reversible defects in it, by exposing it to temperature, gas atmosphere, pressure and a combination thereof. Radiation detection system comprises a photodetector for detecting light pulses from an optically transparent ceramic scintillator of said composition, characterized by a faster decay time, faster rise time, higher time resolution compared to monocrystalline garnets or any combination of these characteristics. For example, the rise time component is less than or equal to 2 ns; and time resolution is less than or equal to 350 ps. Obtained polycrystalline optically transparent ceramic is also characterized by improved oxygen diffusion into grain boundaries, substantially uniform distribution profile of dopants, higher density or reduced porosity compared to polycrystalline optically transparent ceramics combined in an inert gas atmosphere.

EFFECT: invention enables to exclude expensive lutetium from the composition of ceramics, use of iridium crucibles in synthesis of ceramics and thereby reduce power consumption.

34 cl, 5 dwg, 2 tbl