Reaction of Hydrazine with a Chlorine-Terminated Si(111) Surface

Interaction of hydrazine with Cl-terminated Si(111) surface was explored in order to understand the pathways for obtaining a reactive functionalized silicon surface that is oxygen-free. Hydrazine-functionalized Si(111) surface with Si–NH–NH–Si species was prepared starting with Cl-terminated Si(111) surface in a reaction with anhydrous hydrazine at 35 °C. This process was followed by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry to characterize the modified surface. DFT calculations were performed to supplement the analysis, to identify major surface species resulting from this reaction, and to provide a mechanistic insight into the initial stages of modification. This work provides a new pathway to obtain a well-defined functionalized silicon surface with a Si–N interface that is oxygen- and carbon-free and that can be used for further functionalization or deposition schemes