Ge-on-Si Bufferless Epitaxial Growth for Photonic Devices

Abstract

Demonstration of bufferless fully crystalline Ge-on-Si is shown. Si-Ge interdiffusion is limited to 10nm. One dimension lateral constrain provides a mechanism to prevent the formation of polycrystalline material. TEM, SEM and XRD analysis confirms Ge crystallinity. PL shows that dopant concentration is retained avoiding the dopant sink that the Ge buffer provides. Dopant concentration is retained at high levels of 1019cm-3 for n-type. Preliminary results exhibit a dopant surfactant effect determining changing the required channel dimensions for crystallinity with the dopant concentration and type used.