Octadecyltrichlorosilane monolayers as ultrathin gate insulating films in metal-insulator-semiconductor devices

Abstract

In order to fabricate metal-insulator-semiconductor (MIS) devices with gate insulating films thinner than 5.0 nm, organic monolayers have been grafted on the native oxide layer of silicon wafers. We demonstrate that a single monolayer of octadecyltrichlorosilane with a 2.8 nm thickness allows to fabricate a silicon based MIS device with gate current density as low as 10−8 A/cm2 at 5.8 MV/cm, insulator charge density lower than 1010 cm−2, fast interface state density of the order of 1011 cm−2 eV−1, and dielectric breakdown field as high as 12 MV/cm. Moreover, this insulating film is thermally stable up to 450 °C.