AFM-IR (Atomic Force Microscope InfraRed) is a general term for techniques based on detecting mechanical response of the AFM cantilever upon pulsed illumination of sample with IR light. AFM-IR is typically utilized for sample absorption mapping and spectroscopy of materials with relatively large absorption coefficient (polymers, organic materials, etc.).
Basic probing principle:
- focus pulsed IR laser light onto sample;
- illuminated sample absorbs IR radiation and thermally expands, exerting force on the AFM tip and stimulating cantilever motion;
- cantilever motion is detected using standard AFM technology, delivering thermal expansion maps and spectra for spectroscopic IR analysis.
Challenge: Detecting small expansion of nanoparticle and thin films relies on the mechanical enhancement provided by a cantilever resonance. The cantilever resonance shifts depending on the local sample mechanics (e.g. sample stiffness, dissipation, etc. ) and measurement conditions, thus coupling optical and mechanical sample properties in the AFM-IR signal and resulting in:
poor sensitivity misleading image contrast mechanical artifacts irreproducibility due to varying operating conditions
Solution: neaspec’s tapping AFM-IR+ actively tracks the cantilever resonance, ensuring the maximum resonant enhancement and helping to decouple the optical sample properties from the mechanical properties, which provides:
best possible sensitivity absence of mechanical artifacts in AFM-IR+ images ability to extract pure optical interaction excellent reproducibility
List of neaspec AFM-IR technologies:
- tapping AFM-IR+: tapping mode AFM-IR imaging & spectroscopy.
- PTE+: contact mode AFM-IR with resonance enhanced sensitivity.
- PTE: legacy contact mode PTE technique suitable for thick sample.
Compare different AFM-IR technologies and learn why neaspec is the market leader
- High-quality nanoscale-resolved chemical imaging
- High sensitivity even on ultrathin layers with tapping AFM-IR+ on
- Sub-10 nm resolution demonstrated on PS-PMMA block copolymer
- No mechanical artifacts in tapping AFM-IR+ images for true optical mapping & hyperspectral analysis
- Excellent sensitivity: AFM-IR+ detects even the weakest vibrational signatures for precise chemical identification
- Excellent reproducibility even for the weakest spectral features and fast acquisition speeds
Simple Setup
No need for interferometric measurements and optical detection results in less capable yet simpler setup compare to s-SNOM
Cost Efficient
Purely mechanical detection reduces demand for the illuminating laser quality, resulting in larger compatibility and wider spectral coverage per invested money
Top Performance
neaspec is an unsurpassed expert & technological leader in light focusing onto the tip, delivering maximum performance with minimum laser power for preventing sample & tip degradation
