Selective Epitaxial Growth of Germanium on Si Wafers with Shallow TrenchIsolation: An Approach for Ge Virtual Substrates

摘要

Ge selective epitaxial growth (SEG) in shallow trench isolatedrnwindows is of great interest in advanced devices due to the goodrnlateral electrical isolation of shallow trenches and the possibility ofrnintegrating Ge on Si wafers. However, the high density ofrnthreading dislocations in strain-relaxed Ge layers and facetrnformation are two major concerns in Ge SEG. In this work, wernhave obtained facet-free growth of Ge in shallow trench isolated Sirnwindows with a threading dislocation density (TDD) of 4.2×108rncm-2. A mass transport model is developed to simulate the Gernfaceting and the factors influencing the Ge deposition selectivityrnare studied.