Investigations of growth conditions for InP suited for micro opto electro mechanical systems for data communication

Abstract

InP based micro-mechanical systems rely on a well-controlled stress within the structural InP layers. During the growth of InP, residual arsenic atoms from the previous InGaAs growth are incorporated into the crystal causing a compressive stress gradient. We present a method to reduce the gradient strain by changing the growth sequence of the InGaAs/InP heterostructure. The InGaAs layer is covered with a thin InP cap enabling an extended growth interrupt prior the growth of the structural InP layer. The presented growth procedure enables the growth of low gradient stress InP suited for the fabrication of micro-mechanical devices. To demonstrate the feasibility of the proposed growth sequence on a device fabrication level, a tunable resonant cavity light emitting diode has been grown, micromachined, and characterised.