Effect of High Temperature and High Current Stress on Richardson Plots of TiAl/GaAs and TiptAu/GaAs Schottky Diodes

Effect of high temperature and high current stress on I~V characteristics and Richardson plots of TiAl/GaAs and TiptAu/GaAs Schottky diodes are studied. It is found that as stressing time increases, for TiAl/GaAs Schottky diode, the banter height decreases rapidly, the product of Richardson constant SA^* and area S of diode decreases quickly, whereas for TiptAu/GaAs Schottky diode, the barrier height and the product of SA^* and S increase first and then trends to be a constant. In the I~V characteristics, as stressing time increases, the saturation current of TiAl/GaAs Schottky diodes increases, for TiptAu/GaAs Schottky diodes, the saturation current decreases first and then trends to be a constant. These results have been attributed to the intermetallic compounds formed formed in the metal/GaAs interface.