[19p-E310-1~20] 15.4 III-V-group nitride crystals

[19p-E310-5] A study of distribution of residual stress on n type GaN in contact with the Au/Ti/Cr film electrode by micro-Raman imaging in high temperatures

〇Jun Suda¹, Motoki Kawase¹, Sousuke Imai¹, Ryoga Fuji¹ (1.Chukyo Univ.)

Keywords:widegap semiconductor, residual stress, micro-Raman imaging

As an ideal material for high power devices, properties of n-type GaN single crystals at different temperatures, especially at high temperatures, are significant to its practical applications. However, using widegap semiconductor as MOS-FET for high-power inverter in higher temperatures than 200℃ in general, the difference of values in thermal expansion coefficient between an electrode contact and the surface of widegap semiconductor would lead to peeling of an electrode and a crack on the electrode contact interface. In this study, we perform 3D-Raman imaging measurements on n-type GaN single crystals in contact with the Au/Ti/Cr multilayer film electrode in high temperatures and discuss distribution of residual stress in n-type GaN in contact with the Au/Ti/Cr electrode film by comparison with those by FEM calculations.