Dislocation-induced deep electronic states in InP: Photocapacitance measurements

作者：Oyama Yutaka^*; Nishizawa Jun ichi; Kimura Toshihiro; Tanno Takenori

来源：Physical Review B, 2006, 74(23): 235210.

DOI：10.1103/PhysRevB.74.235210

Photocapacitance and excitation photocapacitance methods were applied to reveal the dislocation-induced deep levels in coalescent epitaxial lateral overgrowth layers of InP. Point-contact Schottky barrier junctions with small junction areas were formed on dislocated and dislocation-free regions by using wedge wire-bonding of Au, and photocapacitance measurements were then carried out at 30 K. In the dislocation-free layers, the dominant deep level was located at 1.30 eV below the conduction band, whereas in the dislocated area, dominant deep levels were detected at 0.86 eV (lambda=1.44 mu m) and 1.05 eV (lambda=1.18 mu m) below the conduction band. A neutralized state was also detected at 0.66 eV above the valence band. From the detailed excitation photocapacitance results, it is shown that the defect configuration coordinate diagram of the dislocation-induced deep levels was considered with large Frank-Condon shifts (d(FC)) of 0.28 eV. This means that the atomic configurations around the deep levels are highly relaxed, as expected from the structures of the dislocation cores.

• 出版日期2006-12