Transfer-Free Growth of Bi2O2Se on Silicon Dioxide via Chemical Vapor Deposition

The bismuth oxyselenide (Bi2O2Se) is considered as an alternative to graphene (zero band gap), black phosphorus, and molybdenum sulfide (MoS2) due to its sizeable band gap and high carrier mobility. To date, Bi2O2Se is fabricated on the top of mica using two to three sources under dual heating zones inside a chemical vapor deposition tube followed by its transfer on a desired substrate for particular device application. Herein, we have proposed an entirely new growth mechanism to synthesize Bi2O2Se directly on silicon dioxide (SiO2) using single source bismuth selenium (Bi2Se3) to get rid of the transfer process. The asgrown Bi2O2Se flakes were mechanically, structurally, and topographically investigated to ensure the quality of flakes. Young's modulus 65 GPa of as-grown Bi2O2Se is thickness dependent, indicating the successful fabrication of Bi2O2Se on SiO2 as the Young's modulus of Bi2Se3 similar to 44-58 GPa is far lower than that of Bi2O2Se. The structure of as-synthesized Bi2O2Se provided evidence of successful fabrication of Bi2O2Se on SiO2. The field-effect-transitor device showed n-type semiconducting material with high current on/off ratio (similar to 10(8)) and field-effect mobility of similar to 70 cm(2) V-1 s(-1) which is comparable to those of traditional transition metal dichalcogenides. Technologically, the transfer-free growth of Bi2O2Se will generate high-quality hybrid material on SiO2, which can play a crucial role in highly efficient electronics.