Near-midgap deep levels in Al0.26Ga0.74N grown by metal-organic chemical vapor deposition

作者：Sugawara Katsuya^*; Kotani Junji; Hashizume Tamotsu

来源：Applied Physics Letters, 2009, 94(15): 152106.

DOI：10.1063/1.3119643

• aluminium compounds
• deep level transient spectroscopy
• electron emission
• gallium compounds
• III-V semiconductors
• semiconductor thin films
• wide band gap semiconductors

A deep level with an activation energy of 1.0 eV in n-type Al0.26Ga0.74N grown by metal-organic chemical vapor deposition was detected by deep-level transient spectroscopy (DLTS) with a sampling time window of several seconds. The deep-level density was 6x10(15) cm(-3). At the temperatures around which the DLTS peaks were observed, capacitance transient was measured. Under the dark condition, a capacitance increase was observed, corresponding to the thermal emission of electrons from the level with 1.0 eV activation energy. After that, we observed a large capacitance increase under illumination with 2.3 eV photon energy. On the basis of potential simulation taking account of deep levels, we found that the photoinduced capacitance change arose from electron emission from additional near-midgap levels in energy ranging from E-C-1.5 to E-C-2.3 eV.

• 出版日期2009-4-13