Growth study of self-assembled GaxIn1-xAs islands on InP

The growth of self-assembled tridimensional (3D) islands has been increasingly studied lately to produce quantum dots. This technique is the most promising for fundamental studies in a zero dimensional semiconductor system as well as for micro-optoelectronics devices applications, such as lasers and memory devices. The use of 3D-islands has however been limited by the lack of control of their size uniformity and of regular organization on the substrate surface. We proposed to use InAs 3D islands as trapping zones in photorefractive structures on InP substrates. For this application, we need islands which deeply confine the carriers for an efficient trapping mechanism. The islands also have to be dense enough to avoid any lateral diffusion of the carriers. In this work, we study the growth of InAs and Ga_xIn_1-xAs layers compressively strained on InP, in order to produce 3D islands which fulfil these requirements. The optical and structural properties of the islands have been characterized by photoluminescence (PL) and atomic force microscopy (AFM) respectively. We have been able to correlate the optical and structural properties of the islands by performing the PL and AFM measurements on the same structure for InAs and Ga_xIn_1-xAs islands. Finally, we compare the growth of Ga_xIn_1-xAs islands on (100) and (311)B InP substrates, for two Ga_xIn_1-xAs compositions