Effect of annealing processes on the electrical properties of the atomic layer deposition Al2O3/In0.53Ga0.47As metal oxide semiconductor capacitors

The influence of different annealing processes including post deposition annealing (PDA) and post metallization annealing (PMA) with various temperatures (250-400 degrees C) and ambient [N-2 and forming gas (FG)] on the electrical characteristics of Pt/Al2O3/In0.53Ga0.47As MOSCAPs are systemically studied. Comparing to samples underwent high PDA temperature, the higher leakage current has been observed for all of samples underwent high PMA temperature. This has resulted in the degradation of capacitance-voltage (C-V) behaviors. In conjunction with the current-voltage (J-V) measurement, depth profiling Auger electron spectroscopy (AES) and high-resolution transmission electron microscopy (HRTEM) analyses evidence that the out-diffusion of metal into oxide layer is the main source of leakage current. The noticeable passivation effect on the Al2O3/InGaAs interface has also been confirmed by the samples that underwent PDA process. (C) 2014 The Japan Society of Applied Physics