Publications by authors named "Kihyun Keem"

Top-gate ZnO nanowire field-effect transistors (FETs) with Al2O3 gate dielectric layers as storage nodes were fabricated and their memory effects were characterized in this work. The Al2O3 layers deposited on the ZnO nanowire channels were utilized not only as gate dielectric ones but also as charge trapping ones. For a representative top-gate ZnO nanowire FET, its I(DS)-V(GS) characteristics for the double sweep of the gate voltages exhibit the counterclockwise hysteresis and the threshold voltage shift.

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Article Synopsis
  • The study investigates the electrical properties of NOT and NAND logic circuits made from top-gate ZnO nanowire field-effect transistors (FETs) with high-k Al(2)O(3) gate layers.
  • Two identical FETs were connected to create a NOT logic circuit, featuring a high I(on)/I(off) ratio of around 10^8, demonstrating effective voltage transfer with a logic swing of 98%.
  • The paper also discusses the design and performance of a NAND logic circuit that consists of three top-gate FETs connected in series within a single nanowire channel.
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Omega-shaped-gate (OSG) nanowire-based field effect transistors (FETs) have attracted a great deal of attention recently, because theoretical simulations predicted that they should have a higher device performance than nanowire-based FETs with other gate geometries. OSG FETs with channels composed of ZnO nanowires were successfully fabricated in this study using photolithographic processes. In the OSG FETs fabricated on oxidized Si substrates, the channels composed of ZnO nanowires with diameters of about 110 nm are coated with Al(2)O(3) using atomic layer deposition, which surrounds the channels and acts as a gate dielectric.

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