| 摘要 |
A system for measuring thin film stress, anisotropic or isotropic, such as from thin film deposition onto semiconductor substrates found in semiconductor manufacturing. The system uses resettled volume difference, V2-V1, of the surface of a material to calculate stress. The system includes a means to collect 3D surface points, a method to calculate volume and a method to calculate thin film stress from resettled volume difference. Calculating stress from resettled volume difference, V2-V1, eliminates the inaccuracy of calculating stress from the change in surface curvature or surface radius with equations such as ( 1 R 2 - 1 R 1 ) . The inaccuracy of stress calculated from surface curvature is from the non-spherical deformation of anisotropic materials, such as semiconductor substrates, eg: silicon wafers in semiconductor manufacturing. |
