A Low Detection Limit and High Sensitivity Three-Dimensional Structured X-Ray Detector

A novel and highly sensitive X-ray detector with three-dimensional structured electrodes (3D-SiC) has been prepared on a high-resistivity silicon carbide substrate. The detector consistently demonstrates a low leakage current of 7.1 pA and 280 pA with the bias of 200 V at room temperature and 150°C, respectively. In the X-ray response test, the 3D-SiC detector exhibits high 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">${5}.{65}\times {10} ^{{4}}~\mu $ </tex-math></inline-formula>C<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\cdot $ </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">$_{\text {air}}^{-{1}}\cdot $ </tex-math></inline-formula>cm<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-{2}}$ </tex-math></inline-formula>. Meanwhile, it exhibits a linear response to dose rates ranging from 0.67 to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.02~\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">$_{\text {air}}\cdot $ </tex-math></inline-formula>s<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-{1}}$ </tex-math></inline-formula>. So, the detection limit could be calculated as low as 6.92 nGy<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\text {air}}\cdot $ </tex-math></inline-formula>s<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-{1}}$ </tex-math></inline-formula>. Comparing with planar semiconductor-based X-ray detectors, 3D-SiC detector shows ultra-high sensitivity with extremely low detection limit at room temperature. This characteristic renders it potentially advantageous in domains characterized by limited X-ray detection and imaging capabilities, such as the field of X-ray medical diagnosis.