Vacancy
OutlineWettability influenced by vacancy
Vacancy Detect Instrument
X-ray photoelectron spectroscopy (XPS)
X-ray Absorption Spectroscopy (XAS)
Scanning Electron Microscopy (SEM-CL)
Transmission Electron Microscopy (TEM)
Scanning (STM)
Cataluminescence
Vacancy on Surface
surface structure and composition
hydrophilicity
examine surface property
X-ray photoelectron spectroscopy (XPS)
Principle of XPS
𝑬𝒑𝒉=𝒉𝝂−𝑬𝒃−𝝓: kinetic energy of the photoelectron : Planck constant : frequency of X-ray : binding energy of electron on inner orbit: work function dependent on both the spectrometer and the material
Chemical Shift of XPS
unneutral atom due to different electronegativity
- the more electronegative
local negative 𝑬𝒑𝒉↑ ,𝑬𝒃↓
- the less electronegative
local positive 𝑬𝒑𝒉↓ ,𝑬𝒃↑
XPS Spectrum (ZnO)
With the area of each signal,one can compare ratio of theconcentration
XPS Spectrum at Different Annealing Temperature
- as the annealing temperature increasing
ratio of vacancy rises
- in a vacuum environment
more easier to form vacancy
Hydrophilicity and Vacancy
with the concentration of vacancy increase
the surface will be more hydrophilic