シリコン基板上窒化物半導体の高品質化に関する研究

Abstract

Growth of a high quality GaN on a silicon substrate has been attempted. In order to prevent Ga-Si reaction at high temperatures, an AlInN alloy was tested as the intermediate layer between the GaN grown layer and the Si substrate. It was found that a film as thin as 6nm reduces the threading dislocation density in the GaN top layer. In a carbon doped AlGaN on Si, FTIR spectra showed a new specific signal at 945cm-1 following a strong signal at 888cm-1 due to Al-N bond. The new signal was attributed to the LVM due to Al-C bond. This suggests that the carbon has been doped on the nitrogen site to be an acceptor in the AlGaN.