Session 2C: Inaugural Lectures by Fellows/Associates

Naba Kumar Mondal, Saha Institute of Nuclear Physics, Kolkata

Amorphous carbon thin film: An emerging electronic material

The excellent mechanical properties of monolayer amorphous carbon (a-C) thin films (an analog of graphene) with high deformation tolerance are expected to be useful for flexible electronics. The fabrication of high-performance wafer-scale electronic devices both on flexible and solid substrates, exploiting the excellent properties of a-C thin films will be discussed. The speaker will describe the unprecedented anisotropic conductivity of their synthesized amorphous carbon (a-C) thin films and an unconventional conversion concept of transforming a rigid metal circuit into a foldable circuit. Since the synthesized a-C thin film has electrical transparency only in the vertical direction (anisotropic conductivity), the metal/a-C hybrid board reflects the complexity of the underlying metal circuit board. The a-C thin film electrically connects the cracked area of the metal line; thus, the hybrid circuit board is foldable without resistance change during repeated folding cycles. Then, the speaker will also discuss the remarkable performance of a-C thin films as an interfacial layer between gate dielectric and semiconductors in a thin film transistor device, where the interfacial a-C thin film reduces the interfacial trap state densities and increases the electronic mobility 7 times and On/Off ratio three-fold. A foldable perovskite light-emitting diode (PeLED) and a biaxially-stretchable alternating current electroluminescence (ACEL) display will also be discussed, which were fabricated using highly conductive transparent deformable Au film electrodes, synthesized utilizing a-C thin films. Finally, the speaker will discuss the fabrication of a highly flexible pixelated ACEL display by a highly conducting pyrolyzed carbon (Py-C) ultrathin film synthesized from a-C thin films directly on various target substrates.