Abstract
Metal/GaAs or insulator/GaAs interfaces with a sulfur interlayer have been investigated using photoemission spectroscopy and the X-ray standing wave (XSW) method in order to determine the structure and chemical bonding at the interface and further correlate this with the electrical properties. It is found that while a CaF 2 overlayer is not very reactive towards the S interlayer, deposited Al strongly reacts with the surface S-Ga layer to form a thermodynamically stable Al-S interface monolayer, which plays a role in achieving metal-dependent Schottky contact. On the other hand, reactive Pd metal disrupts the S-passivated GaAs surfaces, resulting in surface segregation of sulfur. In this case, the Schottky barrier heights are identical to Pd/GaAs, indicating the importance of S remaining at the interface. XSW analysis reveals that the CaF 2 and Al/S/GaAs systems have well-ordered interfaces. Thus, the stability of the S passivation layer is discussed in terms of the S-Ga binding energy and the reactivity of the deposited overlayer.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
