Dopant diffusion barrier properties of ultrathin, chemically grown oxide films

Abstract

The dopant diffusion barrier property of a chemically grown oxide (CGO) film has been characterized in polysilicon. The CGO film was grown by immersion of an amorphous Si film in a mixture of H 2O 2, NH 4OH, and H 2O liquids, heated to 55°C. The 4.7 Å CGO film behaves as a superior dopant diffusion barrier compared to a 12.7 Å thermally grown oxide (TGO) film. Composition analysis shows the CGO film has 0.4 atom % N while the TGO has no detectable N. The superior barrier property of the thinner CGO film is attributed to N incorporation. © 2005 The Electrochemical Society. All rights reserved.