title: Controllable dissociations of PH3 molecules on Si(001).
abstract: We demonstrate for the first time to our knowledge that controllable dissociation of PH3 adsorption products PHx (x = 2, 1) can be realized by STM (scanning tunneling microscope) manipulation techniques at room temperature. Five dissociative products and their geometric structures are identified via combining STM experiments and first-principle calculations and simulations. In total we realize nine kinds of controllable dissociations by applying a voltage pulse among the PH3-related structures on Si(001). The dissociation rates of the five most common reactions are measured by the I-t spectrum method as a function of voltage. The suddenly increased dissociation rate at 3.3 V indicates a transition from multivibrational excitation to single-step excitation induced by inelastic tunneling electrons. Our studies prove that selectively breaking the chemical bonds of a single molecule on semiconductor surface by STM manipulation technique is feasible.
authors.affiliation: Department of Physics, The Chinese University of Hong Kong, Shatin, New Territory, Hong Kong, People's Republic of China. Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621908, People's Republic of China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Liu
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Lei
authors.forename: Xiji
authors.initials: X
authors.lastname: Shao
authors.forename: Fangfei
authors.initials: F
authors.lastname: Ming
authors.forename: Hu
authors.initials: H
authors.lastname: Xu
authors.forename: Kedong
authors.initials: K
authors.lastname: Wang
authors.forename: Xudong
authors.initials: X
authors.lastname: Xiao