Temperature-dependent electrical properties of the sputtering-made n-InGaN/p-GaN junction diode with a breakdown voltage above 20Â V

The n-InGaN/p-GaN junction diode including its electrodes and semiconductor materials was totally made by magnetron sputtering. Sputtering targets for n-InGaN and p-GaN films were made by hot pressing the mixture of metallic and nitride powders. n-InGaN film had 16 at% In and p-GaN had 10% Mg. After the I-V electrical measurements at room temperature, the diode showed the turn-on voltage of 2.1 V, the leakage currents of 4.7×10−7 A at −5 V and 1.04×10−5 A at −20 V, the breakdown voltage above 20 V, the barrier height of 0.60 eV, and the ideality factor of 5.9. The variations of electrical properties with the test temperature were also investigated up to 150 °C. The I-V characteristics of our p-n diodes can be successfully explained with the thermionic-emission (TE) model. Cheungs׳ and Norde methods were used to extract all electrical parameters of the p-n junction diodes. Our n-InGaN/p-GaN diode has low leakage current without failure at a reverse bias of 20 V.