NANO 225 Intro to Nano/Microfabrication Other Characterization Techniques

Composition Analysis Wet Chemistry Techniques Physics Techniques Liquid or Vapor Phase Chromatography Spectroscopy in UV-Vis region Physics Techniques Solid Phase Inputs Particle (electrons) or X-rays In Vacuum Nano-friendly

X-ray Emission Spectroscopy e- transition e- beam in Characteristic x-ray out ejected electron Energy Dispersive Spectroscopy (EDS) Wavelength Dispersive Spectroscopy (WDS)

X-Ray Fluorescence Spectroscopy e- transition Characteristic x-ray out x-ray in ejected photoelectron

XRF Bulk analysis of elemental composition ~1mm beam diameter ppm or ppb sensitivity ~1mm beam diameter Quick quantitative analysis Metals Ceramics Plastics Thickness measurements plating coatings

Surface Chemical Analysis Electron Spectroscopy for Chemical Analysis (ESCA) = X-ray Photoelectron Spectrometry (XPS) Auger Electron Spectrometry Secondary Ion Mass Spectrometry photon or particle emission

Electron Spectroscopy for Chemical Analysis (ESCA=XPS) photoelectron out Photoelectric effect 1906 Einstein x-ray in

ESCA, XPS Electron escape depth (1-3nm) “surface analysis” Chemical Shifts – identification of surface functions

ESCA Chemical Shifts Example PET

Auger Electron Spectroscopy e- transition characteristic Auger electron x-ray or electron in characteristic x-ray re-absorbed Surface analysis Can use electrons or x-rays Mostly electron beam Scanning electron beams allow imaging as well First derivative plots

Sputter Depth Profiling Acquire spectrum Sputter Acquire ……. Depth profile auger ESCA/XPS

Secondary Ion Mass Spectrometry Atomic Billiards Input: particles Ar+, Ga+, Cs+, C60 Output: atomic or molecular fragments

SIMS Example PET .                                                              

X-ray Diffraction Bragg’s Law nl=2dsin(q)

X-ray Diffraction Data Diffractogram Camera images

X-ray Diffraction Structure determination

Vibrational Spectroscopy for Organic Structure Characterization Infrared Spectroscopy IR absorption spectrum Fourier Transform data collection (FT-IR) Raman Spectroscopy Raman effect Laser (single l) excitation of vibration modes near-IR, Vis, near-UV Energy causes molecular vibrations (phonons)

Infrared Spectroscopy Continuous IR light in Absorption band out hn1 hn1 hn2 hn2 hn3 hn3 hnx hnn-1 hnn-1 hnn hnn Polar groups are active

Raman Spectroscopy Single wavelength in Rayleigh and Raman scattered light out hnx-n hnx-2 hnx-3 hnx hnx hnx-(n-1) hnx-n Rayleigh: elastic Raman: inelastic (Stokes / Antistokes) Nonpolar groups are active

Infrared (Vibrational) Spectroscopy Analysis of organic molecules or covalently bonded inorganics

Raman and IR Spectra Example PET Raman IR

Properties of Interest Electrical Mechanical Optical Thermal

Electrical Properties Conductivity s = enm Hall effect Mobility measurement Capacitance – Voltage profile Carrier concentrations

Electrical Properties Dielectric constant (permittivity) Dielectric strength Magnetic permeability

Band Structure Valence and Conduction bands Optical spectroscopy Optical gap in UV-Vis

Mechanical Properties Tensile testing Stress-strain curves Stress=modulus · strain (Hooke’s Law) Modulus

Nano-indentation Nanometer-scale stress-strain curves Load (mN) Displacement (nm)

Thermal Properties Coefficient of thermal expansion Heat Capacity b=1/V (DV/DT) Heat Capacity C = DQ/DT Thermal conductivity k= DQ/Dt (L/ADT) Melting point Crystallization point Glass Transition

Optical Properties Index of refraction n = c/v Extinction coefficient ellipsometry Absorption and emission spectrum