Open AccessНезаполненные электронные состояния и формирование интерфейса между пленками диметил замещенных тиофен- фенилен соолигомеров и поверхностью окисленного кремния
Author(s) -
A. S. Komolov,
Э.Ф. Лазнева,
Н.Б. Герасимова,
Ю.А. Панина,
Г.Д. Зашихин,
С.А. Пшеничнюк,
О.В. Борщев,
Софья Александровна Пономаренко,
B. Handke
Publication year - 2018
Publication title -
fizika tverdogo tela
Language(s) - English
Resource type - Journals
eISSN - 1726-7498
pISSN - 0367-3294
DOI - 10.21883/ftt.2018.05.45805.298
Subject(s) - x ray photoelectron spectroscopy , thiophene , phenylene , analytical chemistry (journal) , work function , materials science , substrate (aquarium) , chemical vapor deposition , fermi level , layer (electronics) , chemistry , nanotechnology , electron , polymer , chemical engineering , organic chemistry , oceanography , physics , quantum mechanics , geology , engineering , composite material
The unoccupied electron states and the boundary potential barrier during deposition of ultrathin films of dimethyl-substituted thiophene–phenylene coolygomers of the type of CH_3–phenylene–thiophene–thiophene–phenylene–CH_3 (CH_3–PTTP–CH_3) on an oxidized silicon surface have been studied. The electronic characteristics have been measured in the energy range from 5 to 20 eV above the Fermi level using total current spectroscopy (TCS). The structure of the CH_3–PTTP–CH_3 film surfaces has been studied by atomic force microscopy (AFM), and the atomic compositions of the films have been studied by X-ray photoelectron spectroscopy (XPS). The changes in the maximum intensities measured by the TCS method obtained from the deposited CH_3–PTTP–CH_3 film and from the substrate during increasing in the organic coating thickness to 6 nm is discussed. The formation of the boundary potential barrier in the n -Si/SiO_2/CH_3–PTTP–CH_3 is accompanied by the decrease in the surface work function from 4.2 ± 0.1 to 4.0 ± 0.1 eV as the organic coating thickness increases to 3 nm. The ratio of atomic concentrations C: S in the CH_3–PTTP–CH_3 films well corresponds to the chemical formula of CH_3–PTTP–CH_3 molecules. The roughness of the CH_3–PTTP–CH_3 coating surface was not higher than 10 nm on the ~10 × 10 μm areas as the total CH_3–PTTP–CH_3-layer thickness was about 100 nm.