Defects and Interfacial Structure of Bonded Interfaces

摘要

The growth of lattice mismatched epitaxial layers on a binary compound semiconductor interface can lead to a high density of defects, such as dislocations, that can degrade subsequent device performance. For the direct growth of lattice-mismatched materials, defects continue to dominate the properties and function of heteroepitaxial structures. The development of compliant and wafer-bonded structures has provided an alternative approach to the generation substrates for lattice mismatched epitaxial growth. The nature of the interface between bonded layers has not been extensively explored at present. This interface, consisting of a network of dislocations, can however eventually affect or even dictate the properties of the subsequent devices as well as its reliability. We propose to determine the detailed chemical and physical nature of this interface through the application of both conventional and nanoscale characterization tools. The physical and chemical structure of these interfaces was investigated by FTIR and high-resolution spectroscopies. The impact of thermal stress on these structures, as a measure of their long- term stability, will be assessed in the context of device reliability.