Deposition of High-K Al2O3 Dielectric Films on Graphene via Atomic Layer Deposition for Fabrication of High Transparent Capacitors

In this work, the high transparent capacitors have been prepared on quartz substrates by using graphene as the bottom electrodes. The dense Al 2 O 3 films deposited on the treated surface of graphene by atomic layer deposition (ALD) are served as the dielectric layer of the capacitors. Here. The aluminum-doped zinc oxide (AZO) films are in situ grown on the Al 2 O 3 dielectric by ALD as the top electrodes. The capacitors show that the maximal capacitance is 3.33 fF/u$\mathrm{m}^{2}$ at 10 kHz and the minimum leakage current is $6.3\times 10^{-s}$A/$\mathrm{cm}^{2}$ at 1 V. The graphene-based capacitors are in possession of an average optical transmittance of over 80 %, thus as good candidates for integration in transparent circuits.