Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Impurity free selective interdiffusion of pseudomorphic InyGa1-yAs/GaAs multiple quantum well laser and modulator structures

Deckschichtinduzierte Interdiffusion von pseudomorphen InyGa1-yAs/GaAs MQW Laser- und Modulatorstrukturen

Materials science and technology (1995), Nr.11, S.840-843
ISSN: 0267-0836
Fraunhofer IAF ()
InGaAs/GaAs; Interdiffusion; Spannungsrelaxation; strain relaxation

The cap layer dependence and selectivity of impurity free interdiffusion in molecular beam epitaxially grown pseudomorphic InyGa1-yAs/GaAs multiple quantum well structures with y=0.2 and 0.35 have been studied. The influence of the cap layer composition and deposition technique on the degree of interdiffusion has been investigated using photoluminescence. Whereas variations in compositon are found to result only in small variations in the interdiffusion induced band gap shift, a degree of selectivity suitable for monolithic laser/modulator integration can be achieved by combining electron beam evaporated SiO2 and chemical vapour deposited SiON films as cap layers. In addition, the compatibility of the impurity free interdiffusion process with the fabrication of devices containing highly strained Ino-35Gao-65As/GaAs multiple quantum wells has been demonstrated. Using photoluminescence microscopy and Raman scattering measurements, photoluminescence energy shifts of up to 200 meV have bee n observed without strain relaxation or generation of misfit dislocations, accompanied by a substantial reduction of the photoluminescence line width.