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Radiation measurements are critical in radioanalytical, nuclear chemistry, and biomedical physics. Continuous advancement in developing economical, sensitive, and compact devices designed to detect and measure radiation has increased its capability in many applications. In this work, we presented and investigated the performance of a cost-effective X-ray radiation detector based on the extended gate field effect transistors (EGFET). We examined the sensitivity of Al-doped Zinc oxide (AZO) of varying thicknesses, fabricated by chemical bath deposition (CBD), following X-ray irradiation with low and high doses. EGFETs were used to connect samples for their detection capabilities. As a function of the absorbed dose, the response was analyzed based on the threshold voltage shift, and the sensitivity of each device was also evaluated. We demonstrated that thin films are less sensitive to radiation than their disk-type EG devices. However, performance aspects of the devices, such as radiation exposure sensitivity and active dosage region, were found to be significantly reliant on the composition and thickness of the materials used. These structures may be a cost-effective alternative for real-time, room-temperature radiation detectors.

A new design of the MOSFET dosimeter is being developed in a different study to measure the dose delivered to the tissue layers. Development of zinc oxide-Lead (ZnO-Pb) of different thicknesses fabricated by chemical bath deposition were investigated to study their sensitivity following irradiation using a low absorbed dose that can be used in diagnostic and interventional radiology (9, 36.5, and 70 mGy) and high absorbed dose (1, 5, and 10 Gy) of X-ray. The morphology and structure of the as-prepared films were analysed using FESEM and XRD measurements. The device relies on sensing the changes in the local electric field arising from radiation interactions in the absorber, coupled with the semiconductor materials used in this work—ZnO-Pb as the EGFET. Then the sensitivity of all devices was examined. Generally, thin-film devices showed less sensitivity to X-ray than the disk type. The sensitivity of the thin film dropped from 6.66 mV/to 1.42 mV/Gy, while the sensitivity of the ZnO-Pb disk type was 23.3 mV/Gy, which then dropped to 6.30 6.42 mV/Gy. Furthermore, the disk type ZnO-Pb was exposed to a high absorbed dose and obtained a sensitivity value of 0.08 mV/Gy, while the ZnO-Pb thin film obtained 0.01 mV/Gy. This can be related to the influence of thickness on the sensitivity of the dosimeter. However, the device’s performance characteristics, like sensitivity to radiation exposure and operating dose area, were discovered to be strongly dependent on the materials employed, effective atomic number, and thickness of the materials. Based on the results shown above, these devices might be considered a low-cost candidate for real-time -radiation dosimetry at room temperature. Furthermore, the thickest sample of 1 mm showed better sensitivity to radiation, compared to the thinner samples.

Herein, we investigated the applicability of thick film and bulk disk forms of aluminum-doped zinc oxide (AZO) for low-dose X-ray radiation dosimetry using the extended gate field effect transistor (EGFET) configuration. The samples were fabricated using the chemical bath deposition (CBD) technique. A thick film of AZO was deposited on a glass substrate, while the bulk disk form was prepared by pressing the collected powders. The prepared samples were characterized via X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) to determine the crystallinity and surface morphology. The analyses show that the samples are crystalline and comprise nanosheets of varying sizes. The EGFET devices were exposed to different X-ray radiation doses, then characterized by measuring the I–V characteristics pre- and post-irradiation. The measurements revealed an increase in the values of drain–source currents with radiation doses. To study the detection efficiency of the device, various bias voltages were also tested for the linear and saturation regimes. Performance parameters of the devices, such as sensitivity to X-radiation exposure and different gate bias voltage, were found to depend highly on the device geometry. The bulk disk type appears to be more radiation-sensitive than the AZO thick film. Furthermore, boosting the bias voltage increased the sensitivity of both devices. [ABSTRACT FROM AUTHOR]