Gate voltage dependence of subband structure in a two-dimensional electron gas in AlGaN/GaN heterostructures

✍ Scribed by K Tsubaki; N Maeda; T Saitoh; T Nishida; N Kobayashi

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 133 KB
• Volume: 13
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/s1386-9477(02)00315-6

✦ Synopsis

AlGaN=GaN heterostructure devices have recently been attracting much attention because of their potential for microwave applications. Therefore, the electronic properties of a two-dimensional electron gas (2DEG) in AlGaN=GaN heterostructures have recently been discussed. In this paper, we have studied the subbands of the 2DEG in AlGaN=GaN heterostructures by magnetoresistance measurements for the backgate voltages between 0 and -20 V up to 8 T. Since two kinds of periodic oscillations are observed, the existence of two subbands, the ground-subband and the ÿrst-excited-subband, is conÿrmed. The gate-voltage dependence of the electron concentration in each subband exhibits similar behaviour to the gate-voltage dependence of the electron concentration in AlGaAs=GaAs heterostructures.