Relationship among surface state distribution, recombination velocity and photoluminescence intensity on semiconductor surfaces

• Published in: Applied surface science 1992, Vol.56, p.94-99
• Main Authors: Saitoh, Toshiya, Hasegawa, Hideki
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Physics; Surface and interface electron states
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/0169-4332(92)90221-I

Recombination processes through surface states with arbitrary distributions are analyzed on computer, and the behavior of the band edge photoluminescence (PL) intensity. I PL, is studied. In contrast to previous PL analyses based on an assumption of a constant surface recombination velocity S c, the present result shows that S c is not a constant, but strongly depends on the intensity of the excitation light, ø. The behavior of I PL versus ø is investigated in detail for different shapes and densities of surface states. The effect of fixed surface charge is also analyzed. It is shown that N ss distributions on free surfaces can be determined by a detailed measurement of the ratio I PL/øversusø. The result is applied to actual measurement on chemically etched and sulfur-treated GaAs surfaces.