To probe the development of Si-GaAs superlattices, we performed Si K-edge x-ray absorption measurements on periodic Si delta-doped structures in GaAs, for equivalent Si thicknesses of 0.02, 0.2, 0.5, 1, 2, and 4 monolayers (ML). We detected the presence of both Si-Si and Si-As (or Si-Ga) bonds and followed the variation of the coordination numbers as a function of the equivalent thickness of the Si layers. The Si-Si coordination number was found to gradually increase with increasing thickness, but Si-Si bonds were always detected, even at equivalent Si coverages of 0.02 ML. This indicates that the preferred growth conditions for Si-GaAs superlattices lead to widespread Si clustering and self-compensation, and suggests that lateral growth of such clusters to achieve coalescence may be the main mechanism for Si quantum well development.
Boscherini, F., Ferretti, N., Bonanni, B., Orani, D., Rubini, S., Piccin, M., et al. (2002). Silicon clustering in Si-GaAs delta-doped layers and superlattices. APPLIED PHYSICS LETTERS, 81(9), 1639-1641 [10.1063/1.1502908].
Silicon clustering in Si-GaAs delta-doped layers and superlattices
Bonanni, B;
2002-01-01
Abstract
To probe the development of Si-GaAs superlattices, we performed Si K-edge x-ray absorption measurements on periodic Si delta-doped structures in GaAs, for equivalent Si thicknesses of 0.02, 0.2, 0.5, 1, 2, and 4 monolayers (ML). We detected the presence of both Si-Si and Si-As (or Si-Ga) bonds and followed the variation of the coordination numbers as a function of the equivalent thickness of the Si layers. The Si-Si coordination number was found to gradually increase with increasing thickness, but Si-Si bonds were always detected, even at equivalent Si coverages of 0.02 ML. This indicates that the preferred growth conditions for Si-GaAs superlattices lead to widespread Si clustering and self-compensation, and suggests that lateral growth of such clusters to achieve coalescence may be the main mechanism for Si quantum well development.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.