High Responsivity and Detectivity Graphene-Silicon Majority Carrier Tunneling Photodiodes with a Thin Native Oxide Layer Hong-Ki Park Jaewu Choi 10.1021/acsphotonics.8b00247.s001 https://acs.figshare.com/articles/journal_contribution/High_Responsivity_and_Detectivity_Graphene-Silicon_Majority_Carrier_Tunneling_Photodiodes_with_a_Thin_Native_Oxide_Layer/6534431 A photocurrent amplifier operable at low bias voltages with high responsivity and detectivity is highly demanding for various optoelectronic applications. This study shows majority carrier graphene-native oxide-silicon (GOS) photocurrent amplifiers complying with the demands. The photocurrent amplification is primarily attributed to the photoinduced Schottky barrier height (SBH) lowering for majority carriers. The unavoidably formed thin native oxide layer between graphene and silicon during the wet graphene transfer process plays significant roles in lowering of the dark leakage current as well as photoinduced SBH lowering. As a result, the photocurrent to dark current ratio is as high as ∼12.7 at the optical power density of 1.45 mW cm<sup>–2</sup>. These GOS devices show a high responsivity of 5.5 AW<sup>–1</sup> at an optical power (458 nm in wavelength) of 15 μWcm<sup>–2</sup>, which corresponds to ∼1400% quantum efficiency. Further the response speed is as fast as a few ten-microseconds. Thus, these GOS majority carrier photodiodes show the highest detectivity (2.35 × 10<sup>10</sup> cm Hz<sup>1/2</sup> W<sup>1–</sup>) among previously reported graphene-silicon photodiodes. However, the responsivity decreases with the optical power density due to the increasing recombination rate through the interface states proportional to the optical power density. 2018-06-08 00:00:00 detectivity amplifier photoinduced Schottky barrier height power density Thin Native Oxide Layer GOS devices show responsivity cm graphene transfer process SBH photocurrent majority carrier graphene-native oxide-silicon GOS majority carrier photodiodes show AW Detectivity Graphene-Silicon Majority Carrier Tunneling Photodiodes