Scanning Electron Microscopy
Detailed analysis of surface morphology and composition with nanometric resolution.
O que é MEV
How SEM Images Reveal Surface Morphology at the Nanometer Scale
SEM (Scanning Electron Microscopy) is a microscopy technique that scans a focused beam of electrons across a sample's surface and detects the secondary and backscattered electrons emitted at each point to build a high-resolution image. The result is a topographic image with nanometer-scale resolution and a depth of field far greater than optical microscopy, and when equipped with an EDS detector it can also map the sample's elemental composition point by point. SEM reveals surface texture, particle morphology, fracture surfaces, coating thickness and microstructural defects. Samples are typically prepared as small, dry, conductive (or sputter-coated) solid fragments a few millimeters across.
What sets us apart
We don't hand over a spectrum. We hand over the interpretation.
Any lab can return peaks and numbers. Our report reads the data. Three differences define what we deliver — illustrated below with a real, anonymized case.
Multiple techniques, one integrated report
We don't hand back five loose reports. We cross-reference every technique's results into a single reading — each signal checked against the others — to reach an answer, not a pile of data.
- Contamination investigation — identifying and tracing the source of a foreign species.
- Performance degradation — explaining why a batch behaves outside expectations.
- New supplier validation — proving equivalence before switching.
3 LDPE batches · 4 techniques converge, NMR reveals the difference
In semicrystalline polymer systems, thermomechanical processing variables influence chain conformational dynamics¹. Solid-state NMR resolves chemical environments at the nanometer scale², sensitive to changes not detectable by XRD or FTIR³.
Technical justification anchored in the literature
Every technique choice and every inference in the report is backed by peer-reviewed literature — with citations in the text. The conclusion isn't loose opinion: it's a traceable argument, defensible in an audit and in front of the client.
- Numbered citations linking claim to source
- Official standards and methods referenced per analyte
- Auditable reasoning end to end
Conclusion and expert opinion
The report closes with a clear position, signed by the Principal Investigator: what the data shows, what can't yet be claimed, and the next step. It includes an honest caveat on the limits of inference — what separates a technical opinion from a guess.
- Explicit technical position, not just results
- Inference limits declared honestly
- Next-step recommendation signed by the P.I.
Four techniques confirmed equivalence; only the solid-state NMR revealed the subtle conformational change not distinguishable by conventional QC — a molecular signature consistent with the atypical filtration behavior.
Without the industrial line's parameters, no direct causal correlation can be established — a complementary step is recommended for elucidation.
Aplicações de mercado
Onde a MEV entrega resultados
Market Applications
Pharma
- Drug particle morphology analysis
- Tablet coating uniformity assessment
- API crystal structure analysis
Materials
- Surface defect analysis
- Porosity evaluation
- Failure and fracture analysis
Cosmetics
- Powder particle size and shape
- Emulsion stability studies
- Product texture analysis
FAQ
Frequently Asked Questions about Scanning Electron Microscopy (SEM)
What resolution can scanning electron microscopy (SEM) achieve?
- It depends on the instrument, but modern SEM routinely resolves features down to a few nanometers (typically 1-10 nm at high magnification), far beyond optical microscopy's ~200 nm diffraction limit. The resolution actually achieved on a given sample depends on beam voltage, working distance, and sample conductivity/preparation.
Does SEM tell me the chemical composition of my sample, or only its shape?
- Standard SEM (secondary electron imaging) shows only morphology and topography. Elemental composition requires the EDS accessory (SEM-EDS), which detects characteristic X-rays generated by the electron beam to identify and semi-quantify the elements present at each point or region imaged.
Does my sample need to be conductive for SEM analysis?
- Non-conductive samples (most polymers, ceramics, and biological material) can charge under the electron beam and distort the image, so they are typically sputter-coated with a thin conductive layer (gold, carbon, or similar) before imaging, or imaged in a low-vacuum/variable-pressure mode when coating would compromise the surface feature under study.
Can SEM analyze liquid or hydrated samples?
- Conventional SEM operates under high vacuum, which is incompatible with liquid or fully hydrated samples — these must be dried, frozen, or otherwise stabilized first. Environmental/low-vacuum SEM configurations can accommodate some moisture, but sample compatibility should be confirmed before submission.
What size sample can be analyzed by SEM?
- SEM chambers accommodate a range of sample sizes, but samples are generally mounted on stubs a few centimeters across; larger or irregularly shaped parts may need to be sectioned or a representative sub-sample taken. Sample size and mounting constraints are confirmed per project.
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