TlBr Films for Direct Digital Radiography

Area of Science:

• Materials Science
• Medical Imaging
• Semiconductor Physics

Background:

• Modern X-ray imaging systems are often limited by detector performance.
• Current digital radiography detectors include indirect (scintillator-based) and direct (semiconductor-based) types.
• Existing semiconductor detectors using silicon, amorphous selenium (aSe), or cadmium zinc telluride (CdZnTe) have limitations in attenuating higher energy X-rays.

Purpose of the Study:

• To investigate the performance of thallium bromide (TlBr) films as a novel semiconductor material for hard X-ray imaging.
• To evaluate the potential of TlBr detectors coupled with a readout integrated circuit (ROIC) for enhancing X-ray imaging capabilities.

Main Methods:

• Development and characterization of thallium bromide (TlBr) columnar films.
• Deposition of TlBr films onto a complementary metal-oxide-semiconductor (CMOS) readout integrated circuit (ROIC).
• Evaluation of imaging performance, including resolution and X-ray attenuation properties.

Main Results:

• Thallium bromide (TlBr) demonstrates high atomic number and density, making it suitable for hard X-ray detection.
• The developed TlBr film detector achieved an image resolution of 20 μm.
• The detector consisted of a 1 cm² × 100-μm thick columnar TlBr film deposited on a CMOS ROIC.

Conclusions:

• Thallium bromide (TlBr) is a promising material for next-generation hard X-ray imaging detectors.
• The TlBr/CMOS ROIC detector shows potential for improved performance in medical, research, and industrial X-ray applications.
• Further development could lead to enhanced imaging of higher energy X-rays beyond 20 keV.