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Abstract The design and development of solar‐blind photodetectors utilizing ultrawide bandgap semiconductors have garnered significant attention due to their extensive utility in specialty commercial sectors. Solar‐blind photodetectors that display excellent photosensitivity, fast response time and are produced using cost‐effective fabrication steps will fulfill the performance demands in relevant applications. Herein, highly textured Sn‐doped Ga₂O₃thin film metal‐semiconductor‐metal type deep‐UV photodetectors using a commercially scalable magnetron sputtering method are reported. Commercially achievable growth and fabrication steps are intentionally chosen to demonstrate an economically viable photodetection workflow without compromising the device's performance. In‐depth structural, morphological, chemical, and optical characterization are reported to optimize the configuration for further device fabrication and testing. Under transient triggering circumstances, a fast response time of ≈500 ms is reported, accompanied by a responsivity of ≈60.5 A W⁻¹. The detectivity, external quantum efficiency, and photo‐to‐dark current ratio values are reported as 1.6 × 10¹³Jones, 2.8 × 10⁴%, and 17.4, respectively. The overall device performance and cost‐effective fabrication process for solar‐blind UV photodetection using Sn‐doped Ga₂O₃is promising. The approach holds promise for significant implications toward the development of electronics capable of functioning in extreme environments and exhibits substantial potential for enhancing low‐cost UV photodetector technology. 

Proper derivation of CH3NH3PbX3 (CH3NH3+ = methyl ammonium or MA+; X- = Cl-, Br-, I-) optical constants is a critical step toward the development of high-performance electronic and optoelectronic perovskite devices. To date, the optical dispersion regimes at, above, and below the band gap of these materials have been inconsistently characterized by omitting or under-approximating anomalous spectral features (from ultraviolet to infrared wavelengths). In this report, we present the rigorous optical dispersion data analysis of single crystal MAPbBr3 involving variable angle spectroscopic ellipsometry data appended with transmission intensity data. This approach yields a more robust derivation of MAPbBr3 optical constants (refractive index, n, and extinction coefficient, k) for both anomalous (absorptance) and normal (no absorptance) optical dispersion regimes. Using the derived optical constants for our MAPbBr3 single crystals, illustrative modeled solar cell device designs are presented in relation to non-realistic designs prepared using representative optical constants reported in the literature to date. In comparison, our derived optical dispersion data enables the modeled design of realistic planar perovskite solar cell (PSC) optical performance where the active layer (MAPbBr3) is optimized for maximum solar radiation absorption. We further demonstrate optimized modeled planar PSC designs with minimal parasitic optical absorptance in non-active PSC device layers resulting in improved performance at broad angles of incidence (approximately 0-70°). Our robust derivation of MAPbBr3 optical properties is expected to impact the optical dispersion data analysis of all perovskite analogs and expedite targeted development of, for example, solar cell, light-emitting diode, photo and X-ray/γ-ray detector, and laser system technologies.