Accurate Determination of Defects in the Gate Oxide of Si Metal Oxide Semiconductor Devices by Propane Infiltration

Abstract

A new technique has been developed to determine accurately the location and distribution of defects in layers thermally grown on Si substrates. The technique utilizes selective propane (5% in ) carbonization of the Si surface exposed by oxide pinholes to form well‐defined islands of at the interface. This propane infiltration was performed at 1300°C for times of 2–90 s at reduced pressure (5 Torr). The islands formed at the interface are circular, with a diameter directly related to the size of the oxide pinhole at each location. For a 1000 Å oxide and 15 s reaction time, the island (and hence defect) density was typically ∼700/cm2.