What an AFM Report From MNRDC of Parul University Actually Contains: MountainsSPIP Software, 50+ ISO Roughness Parameters, Grain Size Histograms, and How to Interpret the Excel Output for Coatings, Pharma, and Electronics Research

Thin Film Coating for Solar Cells & Semiconductors at MNRDC, Parul University!

When a researcher submits a sample for AFM analysis at MNRDC, the deliverable is not a single image. The Centre provides a structured output package that includes multiple image types, quantitative roughness data, and grain analysis where requested. Understanding what each component of this package contains and how to interpret the numbers determines whether the AFM data becomes a publication figure or sits unused in a folder.

Read more on – AFM Explained: Contact, Non-Contact, Tapping Mode

The standard AFM output package from MNRDC includes four components:

• 2D Topography Image: A flat, top-down colour map where dark colours represent valleys and bright colours represent peaks. This is the measurement image used for extracting precise height data in nanometres.
• 3D Surface Image: A rendered three-dimensional terrain view that makes the microscopic surface visually intuitive. This is the visualisation image that shows whether bumps are sharp (needle-like) or rounded (hill-like).
• Excel Sheet: Numerical roughness values calculated from the scan data. Contains 50+ ISO-standard S-parameters for surface characterisation.
• Roughness Graph: A line profile extracted from the topography data showing height variation along a selected cross-section of the surface.

LCR Meter & Dielectric Testing at MNRDC, Parul University!

MountainsSPIP (Digital Surf, France) is a commercial image analysis software that MNRDC operates under a paid license. It functions as a professional analytical platform that transforms the raw numerical data from the Nanosurf Core AFM into measurable 3D models, quantitative reports, and publication-quality images.

When the AFM scan completes, the raw output is a large file of height data points arranged in a 256 x 256 grid (256 scan lines, each containing 256 measurement points). MountainsSPIP processes this raw grid into the images and numerical reports that users receive. The software can generate reports with over 50 different ISO-standard roughness values (S-parameters) instantly from a single scan dataset.

Read more about – SEM+EDS: Surface Morphology and Elemental Mapping

Key ISO Roughness Parameters in the Excel Output

The Excel sheet contains dozens of parameters, but researchers most commonly use the following:

• Sa (Arithmetic Mean Roughness): The average height deviation from the mean plane across the entire scanned area. The single most-quoted roughness value in publications. Lower Sa means a smoother surface.
• Sq (Root Mean Square Roughness): Similar to Sa but gives more weight to extreme peaks and valleys. More sensitive to outliers than Sa.
• Sz (Maximum Height): The vertical distance between the highest peak and deepest valley in the scan. Indicates the full range of surface variation.
• Sp (Maximum Peak Height): Height of the tallest peak above the mean plane.
• Sv (Maximum Valley Depth): Depth of the deepest valley below the mean plane.
• Ssk (Skewness): Positive values indicate predominantly peaked surfaces. Negative values indicate predominantly valley-dominated surfaces. Zero indicates a symmetric height distribution.
• Sku (Kurtosis): Values above 3 indicate sharp, spiky features. Values below 3 indicate rounded, gentle features. Exactly 3 indicates a Gaussian (normal) height distribution.

Uncover the Advanced XRD Capabilities & Possibilities at MNDRC, Parul University!

Beyond surface roughness, MountainsSPIP performs grain analysis through threshold segmentation. The software identifies individual grains (distinct particles or features) on the surface and measures each one, producing a histogram that shows the distribution of grain sizes across the scanned area. This is valuable for nanoparticle research, thin film growth studies, and any application where particle uniformity matters.

The grain analysis histogram provides a clear map of the particle size range within a sample. For example, a researcher depositing nanoparticles for a drug delivery application needs to confirm that particle diameters fall within a specified therapeutic window. The AFM grain histogram from MNRDC provides exactly that data.

Understanding the scan parameters helps researchers evaluate the quality and limitations of their AFM data:

• Scan area: 10 x 10 micrometres (standard)
• Resolution: 256 lines (256 horizontal passes from top to bottom)
• Scan speed: 0.78 seconds per line
• Total scan time: approximately 3-4 minutes per image
• Primary mode: Tapping (dynamic) mode, where the tip vibrates and taps the surface hundreds of thousands of times per second
• Tip: Dyna190 Al (silicon, aluminium-coated for laser reflectivity, spring constant k = 48 N/m)
• Approach time: approximately 5 minutes for tip-to-surface approach

Scanning faster than 0.78 seconds per line causes the tip to miss fine details. Scanning slower increases the risk of thermal drift, where temperature changes cause the image to appear smeared. The 0.78-second speed is calibrated to balance detail capture against drift risk.

Read more on – Pin-on-Disc Tribometer Testing at MNRDC

Each AFM scan generates three simultaneous 2D images, not just one:

• Height (Z-axis): The actual topography data used for roughness calculations
• Amplitude: The variation in cantilever oscillation amplitude, which highlights edges and boundaries
• Phase: The phase lag between the driving signal and the cantilever response, which reveals differences in material properties (hard vs soft regions)

Below each 2D image, corresponding line graphs display live data as black and white waves. Operators monitor the alignment of these dual lines during scanning to identify noise or interference, adjusting settings in real time to ensure accuracy.

The Nanosurf Core AFM at MNRDC accepts the following sample types:

• Thin films (e.g., graphene, sputtered coatings)
• Polymers
• Metals
• Semiconductors
• Biological samples
• Maximum sample size: 10 mm x 10 mm x 7 mm

Loose powder samples are not analysed directly on the AFM. If a powder sample is submitted, it must first be compacted into a flat tablet to create a solid surface for the AFM tip to scan without moving particles. The Centre does not provide powder specifications for the AFM instrument.

• Optical lenses: Surface roughness must be below 100 nm to prevent eye irritation. MNRDC roughness reports verify compliance.
• Pharmaceutical tablet coatings: Drug dissolution rate depends on coating smoothness. AFM Sa values confirm whether coating meets formulation specifications.
• Thin film coatings from the Auto 500 sputtering system: Surface roughness of deposited films is measured immediately after deposition without leaving the MNRDC facility.
• Electronics chip surfaces: Nanoscale defects on semiconductor surfaces cause device failure. AFM detects defects before they reach production.
• Battery electrode surfaces: Surface area and roughness directly affect charge/discharge performance.

Read more on – Pharmaceutical Material Characterisation at MNRDC