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Diamond is a highly suitable material for X-ray detectors that can function effectively in harsh environments due to its unique properties such as ultrawide bandgap, high radiation resistance, excellent carrier mobility as well as remarkable chemical and thermal stability. However, the sensitivity of diamond X-ray detectors needs further improvement due to the relatively low X-ray absorption efficiency of diamond, and the exploration of single-crystal diamond array imaging still remains unexplored. In the current work, a 10 × 10 X-ray photodetector array was constructed from single-crystal diamond. To improve the sensitivity of the diamond X-ray detector, an asymmetric sandwich electrode structure was utilized. Additionally, trenches were created through laser cutting to prevent crosstalk between adjacent pixels. The diamond X-ray detector array exhibits exceptional performance, including a low detection limit of 4.9 nGy s−1, a sensitivity of 14.3 mC Gy−1 cm−2, and a light-dark current ratio of 18,312, which are among the most favorable values ever reported for diamond X-ray detectors. Furthermore, these diamond X-ray detectors can operate at high temperatures up to 450 °C, making them suitable for development in harsh environments.

Abstract Along with the increasing integration density and decreased feature size of current semiconductor technology, heterointegration of the Si‐based devices with diamond has acted as a promising strategy to relieve the existing heat dissipation problem. As one of the heterointegration methods, the microwave plasma chemical vapor deposition (MPCVD) method is utilized to synthesize large‐scale diamond films on a Si substrate, while distinct structures appear at the Si‐diamond interface. Investigation of the formation mechanisms and modulation strategies of the interface is crucial to optimize the heat dissipation behaviors. By taking advantage of electron microscopy, the formation of the epitaxial β‐SiC interlayer is found to be caused by the interaction between the anisotropically sputtered Si and the deposited amorphous carbon. Compared with the randomly oriented β‐SiC interlayer, larger diamond grain sizes can be obtained on the epitaxial β‐SiC interlayer under the same synthesis condition. Moreover, due to the competitive interfacial reactions, the epitaxial β‐SiC interlayer thickness can be reduced by increasing the CH4/H2 ratio (from 3% to 10%), while further increase in the ratio (to 20%) can lead to the broken of the epitaxial relationship. The above findings are expected to provide interfacial design strategies for multiple large‐scale diamond applications.

Abstract Physical unclonable functions (PUFs) have emerged as a promising encryption technology, utilizing intrinsic physical identifiers that offer enhanced security and tamper resistance. Multi‐level PUFs boost system complexity, thereby improving system reliability and fault tolerance. However, crosstalk‐free multi‐level PUFs remain a persistent challenge. In this study, a hierarchical PUF system that harnesses the spontaneous phase separation of silk fibroin /PVA blend and the random distribution of silicon‐vacancy diamonds within the blend is presented. The thermodynamic instability of phase separation and inherent unpredictability of diamond dispersion gives rise to intricate random patterns at two distinct scales, enabling time‐efficient hierarchical authentication for cryptographic keys. These patterns are complementary yet independent, inherently resistant to replication and damage thus affording robust security and reliability to the proposed system. Furthermore, customized authentication algorithms are constructed: visual PUFs authentication utilizes neural network combined structural similarity index measure, while spectral PUFs authentication employs Hamming distance and cross‐correlation bit operation. This hierarchical PUF system attains a high recognition rate without interscale crosstalk. Additionally, the coding capacity is exponentially enhanced using M‐ary encoding to reinforce multi‐level encryption. Hierarchical PUFs hold significant potential for immediate application, offering unprecedented data protection and cryptographic key authentication capabilities.