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Nanoscale Characterization of WSe2 for Opto-electronics Applications

  • Nirmal Adhikari (a1), Avra Bandyopadhyay (a1) and Anupama Kaul (a1)


Two dimensional (2D) thin transition metal dichalcogenides are being widely investigated for optoelectronics applications. Here, we report on the interfacial study of WSe2 with photo-absorber materials for efficient charge transport using Kelvin Probe Force Microscopy (KPFM) for solar cell applications. The WSe2 in these experiments was synthesized using Chemical Vapor Deposition (CVD) with a WO3 powder and Se pellets as the precursors, where the selenium was placed upstream in an Ar carrier gas within the furnace at a temperature zone of 260-270°C. For the interfacial analysis, nanoscale KPFM measurements show an average surface potential of 125 meV for the CVD synthesized WSe2 flakes. KPFM measurements signify that a thin layer of WSe2 can be used to suppress back recombination of carriers between the electron transport layer (ETL) and the absorber layer. A proper band alignment between ETL and absorber layer helps to increase the overall device performance, which we will elaborate upon in this work. Capacitance-voltage and capacitance-frequency measurements were measured to study the role of defects.


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Nanoscale Characterization of WSe2 for Opto-electronics Applications

  • Nirmal Adhikari (a1), Avra Bandyopadhyay (a1) and Anupama Kaul (a1)


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