Real-time monitoring of InAs QD growth procedure on InP substrate by spectral reflectance

Using an in situ spectral reflectance (SR) method, we monitored the growth procedure of InAs QD layer on InP substrate grown by low-pressure metalorganic chemical vapor deposition. The surface reconstruction of the InP buffer layer at 530 °C under P-rich condition was determined by the subtraction SR and explained to be (2 × 4)-like structures composed of the image P-dimers and [1 1 0] In-dimers. The [1 1 0] and image SR signals at different wavelengths showed different behaviors, which was interpreted to be caused by As/P exchange reaction and the other diverse surface processes. This analysis was confirmed by the comparison between SR signal and multibeam optical stress sensor data.