Key Technologies Of The Design And Processing Of The Graphene Terahertz Detector

Terahertz has broad application prospects in many fields, such as military radar,electronic warfare, communications, security, imaging, medicine,.etc. There are someaspects of problems exsisting in the present terahertz radiation source, such as the lowoutput power, the high heat radiated noise. The terahertz detection technology becomesthe key of the terahertz technology’s development because of the lack of effectiveterahertz detection technology. Based on the excellent optoelectronic properties ofgraphene, such as high carrier mobility, adjustable energy gap,a kind of graphenenanoribbon terahertz detector is introduced in this thesis, in order to realize the highsensitivity terahertz detection and rapid response.The basic working principles and mathematical models of terahertz detectorsarestudied. Based on the mathematical models, the structural is designed, the simulationand optimization of terahertz detector is completed. The preparation of the graphenenanoribbons detector and the key process technology are researched. A detectorprototype is fabricated, and the test systems of detector is designed and built, in order totest the performance of the detector. Following is the main content:①Grapheneterahertz detector is proposed, according to the requirements of thesensitivity and response time for the terahertz detector, based on the the comprehensiveanalysis of research papers and reviews in this field home and abroad.②The basic principles of graphene band gap control and the photoelectricdetection principle of graphene nanoribbons p-i-n photodiode are studied.Withconsideration of the carrier mobility, carrier diffusion, carrier generation, carrierrecombination, the photoelectric detection mathematical model of graphene terahertzdetector is established on carrier transport equation and Poisson equation. Themechanism of regulation of bilayer graphene by gate voltage is studied, and theresponse characteristics of bilayer graphene terahertz detector is simulated by the finiteelement software COMSOL Multiphysics, based on photoelectric detectionmathematical model. A graphene nanoribbon terahertz detector is designed, and someparameters of nanoribbon is optimized by COMSOL, such as nanoribbon width,i-section length and bias voltage.③The process of the graphene nanoribbon terahertz detector is studied, the ZnOnanowires are directional aligned by the dielectrophoresis.Graphene nanoribbons arrays are produced with the ZnO nanowires physical mask. Using the CMOS processingtechnology, the graphene terahertz detector prototype is fabricated.④The test system of the graphene terahertz detector is studied and built, theperformance of the detector is tested.