X-Ray Stress Measurement of Cu/TiN Films
Tatsuya MATSUE, Takao HANABUSA and Yasukazu IKEUCHI
Abstract: Residual stresses in a coating film will be influenced by undercoatings in a multi-layered film system. The present study investigates residual stresses as well as crystal textures in a two layer copper (Cu)/titanium nitride (TiN) film on a glass substrate. A TiN film was first deposited by arc ion plating on a glass substrate as an under layer. A Cu film was then deposited by RF sputtering on the TiN film deposited by arc ion plating. The crystal texture and residual stress in the deposited films were investigated by X-ray diffraction as a function of film thickness of each layer. Both the Cu film and the TiN film had a strong {111}orientation. The two-exposure method was then used to evaluate residual stresses in the Cu and the TiN films by measuring lattice strains in two directions determined by crystal orientation. The Cu layer had tensile residual stresses of 450`630MPa. These stresses increased with both the film thickness of the Cu layer and the TiN layer. The TiN layer had also in tensile residual stress of 230MPa. Although the texture of Cu and TiN films did not change by annealing at temperatures below 400, the residual stresses in Cu layer decreased with the annealing temperatures, whereas those in TiN layer increased. Key Words:Cu film, Titanium nitride film, RF sputtering, Arc ion plating, Crystal structure, Residual stress, X-ray diffraction