Design, Fabrication, and Performance Analysis of TiO₂ Detector Prototype for X-ray Detection Application

This study demonstrates the potential of TiO 2, a wide bandgap semiconductor, for the detection of X-rays with an energy of ∼8 keV based on its photocurrent response. A TiO 2 film ∼ 330 nm thick was synthesized using the thermal oxidation technique. Titanium/gold (Ti/Au) metallic contact pads were deposited on its top surface in a metal-semiconductor-metal (MSM) configuration. The active channel length between the pads is 120 μm. Comprehensive material characterization of the TiO 2 was conducted using X-ray diffraction (XRD) and laser Raman spectroscopy (LRS), confirming the presence of the purely rutile TiO 2 phase in the fabricated film. Spectroscopy showed strong UV absorption in the 300 to 370 nm range, with an optical bandgap of approximately 3.1 eV. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were utilized to analyze the morphology of the film, indicating the formation of a compact and dense structure with a surface roughness of 36 nm. Dark IV measurements showed that the device is highly resistive, with resistivity in the range of 10 12 Ω · cm. X-ray detection performance of the detector was evaluated under varying X-ray dose rates and bias voltages, demonstrating a linear correlation between photocurrent, dose rate, and bias voltage. Repeatability was confirmed through ten cycles of response measurements at different dose rates, ensuring consistent performance. The device exhibited reliable, efficient, and repeatable X-ray detection with an excellent response and recovery characteristics. These findings highlight the promise of TiO 2 -based detectors for X-ray imaging, medical diagnostics, environmental monitoring, and advanced X-ray sensing applications.