# Electric Field Effect in Atomically Thin Carbon Films

- **DOI:** [10.1126/science.1102896](https://doi.org/10.1126/science.1102896)
- **Rating:** Exemplary (4.6 out of 5)
- **Verdict:** A landmark graphene discovery with convergent transport evidence, constrained mainly by non-scalable mechanical exfoliation.
- **Framework version:** v5.0
- **Pipeline version:** v0.4
- **Evaluation date:** 2026-07-20
- **Evaluation page:** https://www.nabu.science/paper/10.1126%2Fscience.1102896

## Key claims

1. we have been able to prepare graphitic sheets of thicknesses down to a few atomic layers, including single layer graphene, and succeeded in making devices from them
   - Support: Well-supported
   - Type: Primary finding
   - Basis: AFM/SEM imaging and device fabrication are paired with transport measurements across thin films
   - Location: Introduction; Figure 1
2. The films are found to be a two-dimensional semimetal with a tiny overlap between valence and conductance bands
   - Support: Well-supported
   - Type: Secondary
   - Basis: resistivity, Hall, temperature-dependence, and band-overlap estimates converge on the semimetal model
   - Location: Abstract; Figure 2
3. electrons and holes in concentrations up to 1013cm-2 and with room-temperature mobilities ≈10,000 cm2/Vs can be induced by applying gate voltage
   - Support: Well-supported
   - Type: Secondary
   - Basis: field-effect and magnetoresistance mobility estimates agree across reported devices
   - Location: Abstract; Main text, mobility paragraph
4. electronic transport in FLG was strictly 2D
   - Support: Well-supported
   - Type: Secondary
   - Basis: angular Shubnikov-de Haas dependence and BF proportional to Vg directly test dimensionality
   - Location: Main text, Shubnikov-de Haas discussion; Figure 3
5. 2D electronic transport is ballistic at submicron distances
   - Support: Supported
   - Type: Secondary
   - Basis: inferred from mobility-derived mean free path rather than a direct ballistic-transport experiment
   - Location: Introduction; Main text, mobility paragraph

## Strengths

- **Field-opening graphene device demonstration** The article reports preparation of graphitic sheets down to single-layer graphene and fabrication of devices from them. This directly addresses the prior assumption that planar graphene would not exist freely under ambient conditions.
  - Dimension: contribution
  - Location: Introduction and Figure 1
- **Convergent transport evidence** Field-effect conductivity, Hall coefficient reversal, temperature dependence, and Shubnikov-de Haas oscillations all support the two-dimensional semimetal interpretation. Figure 3 adds angular and frequency evidence for strictly two-dimensional carrier behavior.
  - Dimension: methodological rigour
  - Location: Figures 2–3
- **Limitations stated within application framing** The article explicitly notes that graphene transistors have a modest on-off resistance ratio and links that limitation to the absence of a band gap exceeding kBT. It also identifies unresolved carrier-mass behavior rather than forcing the data into the expected theory.
  - Dimension: positioning
  - Location: Main text, final results and transistor paragraphs

## Limitations

- **Supporting methods not fully inspectable** The article repeatedly sends fabrication details and detailed Shubnikov-de Haas analysis to supporting online material [15]. That is typical for a short Science report, but it limits independent assessment of the complete procedure and derivations from the supplied text alone.
  - Dimension: methodological rigour
  - Location: Main text, methods paragraph; Reference [15]
- **Exfoliation limits direct translation** The demonstrated preparation method is repeated mechanical peeling from highly oriented pyrolytic graphite. It is effective for discovery-scale devices but does not establish scalable wafer-level production or industrial integration.
  - Dimension: application pathway
  - Location: Main text, fabrication paragraph
- **Switching ratio remains fundamentally modest** The article reports an on-off resistance ratio below approximately 30 at 300 K and attributes this to thermally excited carriers in a material without a sufficient band gap. This limits immediate transistor competitiveness despite the strong field effect.
  - Dimension: application pathway
  - Location: Main text, final transistor paragraph

## Reliability checks

Caveats (4 of 4 checks).

- **Internal coherence:** Clean. The article is internally coherent across its abstract, main text, figures, and quantitative claims. Carrier-density, mobility, band-overlap, Hall-effect, and Shubnikov-de Haas descriptions align with the reported figures and stated model.
- **Research conduct:** Noted. No ethics approval or preregistration is applicable for this laboratory physics experiment, and no image-integrity concern is evident. Research conduct is noted because important fabrication and detailed analytical procedures are deferred to supporting online material [15], which is cited but not available in the supplied article.
- **Reference integrity:** Clean. All 16 cited references resolved to real publications via PubMed, Crossref, or OpenAlex.
  - References not verified automatically are resolved manually within 24 hours.

## Post-publication record

- **Status:** Clean
- **Summary:** No retraction or expression of concern found in Crossref (includes Retraction Watch).
- **Last checked:** 2026-10-17