Experimental determination of intervalley energy gaps as a temperature function for Ga1−xAlxAs

The forward ln i-v characteristic of metal-compound semiconductor contacts shows abrupt variations of the n ideality factor, which can be explained by assuming that the satellite valleys give a bias dependent contribution to the total current. The knee voltage values at which such variations occur allow the determination of intervalley gaps by means of a simple relationship. We have measured such energy gaps for the Ga_1?xAl_xAs over the temperature range 100–300 K.