LEAKAGE CURRENT MECHANISMS IN STRAINED INGAAS/GAAS MQW STRUCTURES

The reverse leakage current density (Jr) in a range of strained InGaAs/GaAs MQW pin diode structures has been measured. The magnitude of Jr at a particular electric field appears to depend primarily on the factors that determine the average strain of the MQW, thickness of the MQW and the capping layer thickness. Plan view TEM shows that misfit dislocation arrays have formed at both the capping and buffer layer interfaces with the MQW and that the total length of dislocation present correlates with the magnitude of Jr and the strain thickness product of the MQW and capping layer.