Atomic Force Microscopy (AFM)
Also known as Scanning Probe Microscopy (SPM), Scanning Force Microscopy (SFM)
Atomic-force microscopy (AFM) or scanning-force microscopy (SFM) is a type of scanning probe microscopy (SPM), with demonstrated resolution on the order of fractions of a nanometer, more than 1000 times better than the optical diffraction limit. The information is gathered by “feeling” or “touching” the surface with a nano-engineered probe. Piezoelectric elements that facilitate tiny but accurate and precise movements on (electronic) command enable very precise scanning.
Thin films development, semiconductors, MEMS, optical components, coatings, piezoelectric materials, magnetic materials.
Covalent has the following capabilities:
|AFM Modes||Sample||Typical data||Typical Turnaround Time|
|Contact AFM||All types||Surface topography, 3D mapping, Ra, Rq||< 48h|
|Tapping Mode AFM||All types||Surface topography, 3D mapping, Ra, Rq, phase imaging||< 48h|
|Electrostatic (EFM)||Composite Metal, Semiconductor films||Local charge distribution||< 48h|
|Magnetic (MFM)||Magnetic films||Magnetic domain structure, magnetization hysteresis, magnetic coercive field||< 48h|
|Piezo response (PFM)||Piezo materials, MEMS||Piezo domain structure, polarization vector and switching, ferroelectric coercive field||< 48h|
|Peak Force AFM||Thin film||Roughness, Surface topography||< 48h|
|Peak Force Quantitative Nanomecanical (QNM)||Polymer Coating||Mechanical properties (adhesion, modulus and dissipation), Phase imaging, Polymer domains||< 48h|
|Kelvin Probe (AM-KPFM)||Thin films, Semiconductors||Surface potential, work function||< 48h|
|Scanning Capacitance (SCM)||Semiconductor films||films Dopant profile, relative capacitance||< 48h|
- Topography and surface quality: complete 3D model of sample’s surface with a sub-nanometer lateral resolution and sub-Å vertical resolution.
- full 3D/2D topography
- roughness (Ra, Rq)
- step height
- cross sections
- particle counts
- defect analysis
- Mechanical characterization and phase mapping: adhesion, modulus and dissipation
- Magnetic domains, magnetization hysteresis, magnetic coercive field.
- Surface potential and work function.
- Piezoelectric domains, polarization vector and switching, ferroelectric coercive field.
- Electrostatic gradients, capacitance variations.
Uses & Limitations:
- What it is great for:
- Quantified topography/ roughness of very smooth samples
- Best z resolution
- Surface imaging of insulating samples with no extra sample prep
- High definition functional properties mapping (mechanical, electric, magnetic, piezo)
- Imaging topography of samples in liquid
- defect analysis
- Requires expertise for reliable results, even on seemingly easy samples
- No compositional mapping available
Optical Flat Surface (AFM height sensor – 3D render): AFM reveals very fine scratches on this highly polished surface.
Freshly cleaved graphite (AFM height sensor – 2D render, 3D render below): atomic steps are visible on this scan.