Enhanced low-dose x-ray sensing nature of nanocrystalline CaWO4 sensor

• Published in: Sensors and actuators. A. Physical. Vol. 352; p. 114200
• Main Authors: Karthieka, R.R., Anil, Mayaha Elsa, Prakash, T.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2023
• Subjects: Applied bias; High attenuating material; Low dose X-ray sensor; Nanocrystalline thick film; X-ray instigated photocurrent; X-ray instigated photocurrent; Low dose X-ray sensor; Nanocrystalline thick film; High attenuating material; Applied bias
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2023.114200

Extensive research on the development of superior sensitive X-ray sensors by many researchers is due to their increased demand in numerous fields, like medical radiography, security inspection, and scientific research areas. Especially in healthcare, repeated or long-term high-dose X-ray exposure on patients may cause serious health hazards. Therefore, developing a superior sensing low dose X-ray sensor is essential. In this present work, a nanocrystalline CaWO4 thick film above an interdigitated electrode was developed as a direct conversion X-ray sensor that operates at different low doses (mGy) using an intraoral pulsed X-ray (70 keV) machine. The X-ray instigated photocurrent of nano-CaWO4 thick film was examined under different applied bias to obtain superior sensitivity of the device. The nano-CaWO4 thick film exhibit sensitivity of 10 nC/mGycm3 at 0.20 mGy (0.06 s) low dose under 5 V applied bias. A suitable mechanism was proposed to explain the nano-CaWO4 thick film sensing behaviour at different biased conditions. [Display omitted] •Low-dose direct conversion X-ray sensor war developed using high attenuating nano-CaWO4.•The X-ray instigated photocurrent of nano-CaWO4 was studied for different low-doses.•The maximum sensitivity for nano-CaWO4 at 5 V biased condition which was found to be 15.59 and 2.40 nC mGy−1cm−3 at 7.97 and 0.20 mGy dose exposures.