Mechanical stress measurement during thin-film fabrication

摘要

A method and system are provided for determining mechanical stress experienced by a film during fabrication thereof on a substrate positioned in a vacuum deposition chamber. The substrate's first surface is disposed to have the film deposited thereon and the substrate's opposing second surface is a specular reflective surface. A portion of the substrate is supported. An optical displacement sensor is positioned in the vacuum deposition chamber in a spaced-apart relationship with respect to a portion of the substrate's second surface. During film deposition on the substrate's first surface, displacement of the portion of the substrate's second surface is measured using the optical displacement sensor. The measured displacement is indicative of a radius of curvature of the substrate, and the radius of curvature is indicative of mechanical stress being experienced by the film.

主权项

1. A method of determining mechanical stress experienced by a film being fabricated on a substrate, comprising the steps of:
providing a substrate in a vacuum deposition chamber, said substrate having a first surface and a second surface opposing said first surface wherein said first surface is disposed to have a film deposited thereon and wherein said second surface is a specular reflective surface; supporting a portion of said substrate along a circular geometry thereof, said circular geometry having a center; positioning an optical displacement sensor in said vacuum deposition chamber in a spaced-apart relationship with respect to a portion of said second surface located at approximately said center of said circular geometry; depositing a film on said first surface; and measuring, during said step of depositing, displacement of said portion of said second surface using said optical displacement sensor, wherein said displacement is indicative of a radius of curvature of said substrate, and wherein said radius of curvature is indicative of mechanical stress experienced by said film during said step of depositing.