چكيده به لاتين
In recent years, infrared photodetectors based on mercury telluride (HgTe) quantum dots have been extensively studied in various fields due to their excellent optical properties, such as size-tunable absorption, and are considered a cost-effective alternative to devices fabricated using epitaxial growth methods. Among materials produced as quantum dots, HgTe holds a special status, as it is the only material capable of covering the entire infrared spectrum from visible to terahertz (0.7 to 100 micrometers). This unique feature, stemming from its electronic structure, combined with its air stability and charge conduction capability, has driven consistent and extensive efforts over the past two decades to produce and improve HgTe quantum dots.
In this context, we not only review the latest advancements in mercury telluride quantum dot detectors related to material growth and structure design but also report a simulation study of various optical detector structures based on HgTe quantum dots. Notable among these structures is the heterojunction of HgTe quantum dots and silicon, designed for the wavelength range from visible to mid-infrared. Additionally, the concept of introducing porosity in the top electrode results in reduced reflection and demonstrates increased spectral responsivity compared to non-porous optical detector devices. The responsivity and external quantum efficiency (EQE) values of the Si/HgTe QD photodiode structure in the SWIR and MWIR ranges are 0.42, 31.9%, and 0.39, 12.6%, respectively, indicating enhanced performance compared to the planar structure, with results showing good agreement with experimental and fabrication data. Moreover, the design of the structure based on HgTe quantum dots, along with electron transport layers (ETL) and hole transport layers (HTL), achieves an excellent specific detectivity (D*) of approximately 1.6×1010. The design of detector structures based on electron transport layers and hole transport layers in quantum dot-based devices is a novel and emerging concept. Simulation of this structure using various materials, aimed at performance optimization, has resulted in a device with remarkable operational outcomes, including a responsivity of 0.87 A/W and an external quantum efficiency of 28.5%.
