Direct X-ray Detectors Based on PDMS Films With Low Detection Limit and High Flexibility

Abstract

The excellent mechanical properties of Polydimethylsilane (PDMS) has been widely used in hybrid flexible photodetectors, but there is hardly any research on it as the active layer of the direct X-ray detectors. In this letter, the low detection and high flexibility X-ray detector was fabricated based on pure PDMS. The metal/polymer/metal (MPM) vertical structure detector has a detection limit of 49.69 nGy <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{air}\text{s}$ </tex-math></inline-formula> −1. Carrier migration occurs in PDMS under X-ray irradiation with the sensitivity of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$57.7~\mu \text{C}$ </tex-math></inline-formula> Gy <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{air}^{-1}$ </tex-math></inline-formula> cm−2 at the electric field of 2 V/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> and the dose rate of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$23.9~\mu $ </tex-math></inline-formula> Gy <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{air}$ </tex-math></inline-formula> s−1. The device still maintains a good performance after bending tests (different bending radius and 10000 cycles). This work provides a new possibility for the next development of direct X-ray detectors.