Deep hole traps in Be-doped Al0.2Ga0.8As layers grown by molecular beam epitaxy

✍ Scribed by J. Szatkowski; K. Sierański; A. Hajdusianek; E. Płaczek-Popko

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 195 KB
• Volume: 340-342
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2003.09.071

✦ Synopsis

Deep hole traps in Be doped p-type Al 0.2 Ga 0.8 As grown by molecular beam epitaxy have been studied by the deeplevel transient-spectroscopy method applied to samples with a Schottky diode configuration. Six hole traps, labeled as H1-H6, were found. Activation energies and capture cross sections have been determined for all the traps. Hole emission from the traps H1 and H2 was electric field dependent obeying the Poole-Frenkel effect relation. Their thermal activation energies when extrapolated to zero electric field were E T1;0 ¼ 0:31 and E T2;0 ¼ 0:36: For the traps H3-H6 the activation energies for emission were equal to: E T3 ¼ 0:30 eV, E T4 ¼ 0:46 eV, E T5 ¼ 0:55 eV and E T6 ¼ 0:59 eV. Comparison with the data for LPE material indicates that the levels H5 and H6 can be Cu and Fe related, respectively.