[17p-A35-1~6] Recent developments in semiconductor radiation detectors

4:15 PM - 4:45 PM JST(7:15 AM - 7:45 AM UTC)

[17p-A35-6] Development of Large-Area CdTe Photon-Counting X-ray Imager

〇Toru Aoki^1,2, Junichi Nishizawa¹, Hiroki Kase¹, Katsuyuki Takagi^1,2 (1.RIE, Shizuoka Univ, 2.ANSeeN)

Keywords:

semiconductor,CdTe

We have developed a large-area photon-counting X-ray flat-panel detector (FPD) with a 100 µm pixel pitch using Cadmium Telluride (CdTe). The detector employs a 0.75 mm thick diode-type CdTe, connected to an 80 µm ultra-low-power photon-charge counting readout circuit. Each module consists of 96 × 96 pixels, arranged in a 12 × 12 configuration, creating a 4.5-inch FPD.Utilizing ultra-high-precision 3D-IC stacking technology, we thinned the readout LSI and formed TSVs for signal input/output. Metal bump connections were formed on a 100 µm pitch pad using silver-based bump material, enabling flip-chip bonding with CdTe, resulting in a 9.6 mm square module. These modules were tiled on a flat substrate with a 1-pixel gap, maintaining a 40 µm distance between CdTe layers.Signal and power lines cross at 90°, managed by a controller with FPGA and DPS. Key performance characteristics like Detective Quantum Efficiency (DQE) and Modulation Transfer Function (MTF) were discussed.This CdTe-based FPD offers high resolution and sensitivity, suitable for medical imaging, security, and industrial non-destructive testing. The 3D-IC stacking improved interconnection reliability and reduced readout electronics thickness. The precise tiling ensures high spatial resolution and uniform sensitivity, making this innovative CdTe-FPD a significant advancement in X-ray imaging technology.