Bonding strength and electrical characteristics of Si/Si, Si/InP and Si/GaAs interfaces bonded by surface activated bonding at room temperature: influences of sputtering time and energy

摘要

Tensile results show that Si/Si and Si/GaAs samples are fractured through the bulk and Si/InP samples are visibly separated from the bonded interface. The cause of the interface separation of Si/InP is intensively investigated by the X-ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscope (AFM). The evidence of existence of weak indium layers on the debonded Si surface indicates that the Si/InP samples are separated from the interface of In/InP, but not across the bonded interface of Si/In. Interface current decreases with increasing sputtering time and energy. Accumulation of radiation induced defects associated with doping controls interface current. Strong influence of exposure to a UHV atmosphere of the activated surfaces on the interface current of p-Si/p-Si is found to be due to the deposition of residual atoms on the surfaces, which produces impurity states and traps electrons, thereby control interface current.