High Field-Effect Mobility Bottom-Gated Metallorganic Chemical Vapor Deposition ZnO Thin-Film Transistors with SiO[sub 2]∕Si[sub 3]N[sub 4] Bilayer Gate Dielectric

Bottom-gated thin-film transistors (TFTs) on glass substrates were fabricated using ZnO channel layer grown by metal organic chemical vapor deposition with two different gate dielectrics. The gate dielectrics employed were plasma enhanced chemical vapor deposition prepared and bilayer stack. The TFTs employing bilayer gate dielectric exhibit a field-effect mobility of and an on/off current ratio of . The TFTs using only gate dielectric, on the other hand, show a lower field-effect mobility of and a lower on/off current ratio of . The enhancement of device properties is attributed to a better -axis crystal orientation, a larger grain size, and a lower density of point defects in ZnO films grown on the bilayer stack.