The present invention discloses a non-volatile memory device using AIGaN/GaN high electron mobility transistor (HEMT). AIGaN/GaN HEMTs are fabricated and characterized with Gd as the Schottky gate. A capacitance-voltage hysteresis is observed, which is found to be reproducible across device processed and measured under various conditions. The hysteretic nature of the characteristics gives rise to a voltage dependent capacitance window. Deep level trap due to Gd may be potentially responsible for the observed characteristics. he capacitance window is found to remain the same for a very long period of time.