Metal–semiconductor–metal (MSM) structures have been widely used and extensively investigated for ultraviolet (UV) detection. However, traditional MSM structures suffer from large dark currents, narrow detection bands, and low collection efficiency. Optimizing these properties for broadband detection in MSM structures is essential for improving the performance and functionality in broader optoelectronics applications. We report a high-performance broadband graphene/thin silicon/graphene photodetector by realizing a synergistic combination of graphene and silicon absorption bandwidths from the x-ray to near-infrared regions. The sensitivity of the proposed photodetector in this spectral range is greatly enhanced. A high responsivity of 0.56 A/W, a high detectivity of 2.72 × 10¹¹ Jones, and a fast response time of 7.2 ns are achieved. Moreover, the real-time array imaging at broadband regions presented in this study can benefit from the independent pixel structures similar to the complementary-metal-oxide-semiconductor (CMOS) architecture. This approach constitutes a reliable route toward a high-performance photodetector with prominent broad-spectrum response, high responsivity, and low noise. These results will motivate strategies to achieve high-performance, broadband image sensors, compatible for on-chip CMOS circuit technology that advances the development of next-generation graphene/silicon image sensors.

Here, we report a broadband graphene-silicon field-effect coupled detector (FCD) sensitive to photons spanning from soft X-ray to Near-Infrared region. Unlike traditional charge-coupled devices (CCD) relying on serial charge transfer between potential wells, the FCD integrates photo-sensing, charge integration, field-effect amplification, and random readout in one pixel. The charge integration in the potential well of the semiconductor substrate and field-effect coupled amplification in graphene transistor result in a highly sensitive broadband response. In the X-ray region, the device displays a high sensitivity of 1088 CGy _air ⁻¹ cm ⁻² and a fast response time < ~5 ms. Linear array imaging reveals the potential of our devices for array-based broadband imaging. Our FCD offers a viable strategy to monolithically integrate 2D materials into conventional solid-state imaging technology, exploring the next-generation broadband photodetectors for high-quality imaging and super vision technology.

Charge-coupled devices (CCD) allow imaging by photodetection, charge integration, and serial transfer of the stored charge packets from multiple pixels to the readout node. The functionality of CCD can be extended to the non-destructive and in-situ readout of the integrated charges by replacing metallic electrodes with graphene in the metal-oxide-semiconductors (MOS) structure of a CCD pixel. The electrostatic capacitive coupling of graphene with the substrate allows the Fermi level tuning that reflects the integrated charge density in the depletion well. This work demonstrates the in-situ monitoring of the serial charge transfer and interpixel transfer losses in a reciprocating manner between two adjacent Gr-Si CCD pixels by benefitting the electrostatic and gate-to-gate couplings. We achieved the maximum charge transfer efficiency (CTE) of $92.4\%$, which is mainly decided by the inter-pixel distance, phase clock amplitudes, switching slopes, and density of surface defects. The discussion on overcoming transfer losses and improving CTE by realizing a graphene-electron multiplication CCD is also presented. The proof of the concept of the in-situ readout of the out-of-plane avalanche in a single Gr-Si CCD pixel is also demonstrated, which can amplify the photo packet in a pre-transfer manner.

In this work, we demonstrate the instant detection of out-of-plane avalanche multiplication in graphene-oxide-semiconductor structure via strong field-effect coupling of the graphene channel with the silicon photo gate. This in situ detection of out-of-plane avalanche can eliminate carriers’ preamplification losses in traditional avalanche multiplication charge-coupled devices (CCDs). By relying upon the electrostatic coupling, a real-time signature of the space charge region in silicon can be observed by both displacement and channel currents of the device. This allows us to alternatively probe the multiplication capability of the graphene-oxide-semiconductor structure under pulsed laser illumination while the semiconductor is dynamically biased through multiple ramping signals. The operating scheme of the device shows good capability for detecting weak light (45 nW), while the intrinsic self-regulating mechanism helps avoid oxide breakdown. The maximum multiplication factor (MF) of $\sim {10}$ , responsivity of $340 \text {A/{W}}$ , and specific detectivity of $2.85\times 10^{{13}}$ Jones are achieved, respectively.

Two-dimensional materials have modernized a broad interest in electronic devices. Along with many advantages, their atomic-level thickness makes them sensitive under high electrical stress. This work proposes a protection design using a Graphene/Silicon (Gr/Si) Schottky diode as the protective device, which helps to improve the endurance for unwanted fluctuations in operating voltage of 2D heterostructure-based devices. In this scheme, the 2D heterostructure was configured parallel with the protective device (Gr/Si diode) for electrical measurements. It was found that Gr/Si diode handles a large portion of initial surge current peaks, which significantly increases the durability and lifetime of 2D material-based heterostructure devices. This scheme potentially bridges mature CMOS technology and novel 2D-based heterostructure applications for robust futuristic devices.