Nicolas Molina Vergara�Ph.D. candidate in Materials Science & Engineering graduating in May 2026

• Materials Engineer specializing in Process & Metrology with 5+ years optimizing measurement protocols across 20+ analytical techniques.

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• Sole advanced user for a $2.5M+ IONTOF M6 ToF-SIMS at the University of Texas at Austin.

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• Systematic, data-driven problem solver with SOP development, root-cause mindset, and lab leadership mentoring 10+ researchers.

LinkedIn | U.S. Permanent Resident

Google Scholar (100+ citations)

Updated 02/04/2026

• As a Mechanical Engineer and Materials Scientist, I’m passionate about equipment ownership and recipe optimization for high-quality, reproducible metrology.

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• Experienced with 20+ analytical techniques, including data acquisition, analysis, and troubleshooting.

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• Next: some projects I have led end-to-end (with advisor mentorship).

NEXAFS

ToF-SIMS

XPS/REELS

STEM (BF, DF)

FIB/EDS/SEM

(GI)XRD/XRR

Nanoindentation

Ellipsometry

Profilometry

Problem

Approach

Outcome

Relevance

ToF-SIMS data are often normalized using unstable reference signals, which skew material properties.

Model how signal transformations change the governing physics, then derive simple validity checks.

Showed, via literature-based case studies, that drifting references create artifacts for 72% of research articles.

Provides a model-based RCA and CAPA-style controls to improve ToF-SIMS diffusion reproducibility across instruments and materials.

✗

D₂O in MoS₂

Artifactual diffusion curve shapes due to signal normalization

72%

(160 studies)

Problem

Approach

Outcome

Relevance

Diffusion of H₂O/O₂ in thin films is hard to measure because mobile species out-diffuse during analysis.

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Optimize ToF‑SIMS acquisition for high-speed, reliable depth profiling while out-diffusion occurs in real time.

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Enabled first time-resolved ToF‑SIMS depth profiling to extract diffusivity of water/oxygen in MoS₂ films.

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Delivered a documented protocol (settings + checks) for studying out-diffusion with minimal artifacts.

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Water diffusion in MoS₂ thin film with time-resolved depth profiling

*First time poisson statistical error accounted in NLLS fitting

Problem

Approach

Outcome

Relevance

Hydrogen stoichiometry in thin films is not accessible via XPS or EDS, limiting contamination diagnosis.

Adapted a semiconductor standardless ToF‑SIMS processing workflow (FSM approach) to polymer films.

First standardless quantification of hydrogen, including the detection of adventitious contamination.

Enables rapid contamination/oxidation assessment without additional tests or external standards.

Adventitious

Contamination

PTFE film characterization with the novel FSM approach

A small peak at 285 eV in the C 1s spectrum confirms adventitious contamination

*I have successfully applied FSM to MoS₂ thin-films and PtAu_x tribolayers

Problem

Approach

Outcome

Relevance

SNL needed a non-destructive, depth-resolved method to distinguish through-thickness crystallization

Performed ω-dependent GIXRD on the MoS₂ (002) reflection and fit it using a DWBA-based model

ω-GIXRD+DWBA revealed surface-enriched MoS₂ crystallization, consistent with HR‑STEM observations

Delivers a rapid, non-destructive depth‑profiling workflow to model and diagnose buried vs surface crystallinity in thin films

Surface enriched MoS₂ coating revealed by ω-GIXRD + DWBA

*DWBA model: Fresnel transmission + XRR-derived δ/β + Λ

Problem

Approach

Outcome

Relevance

HT exposure can compromise Ag thin‑film integrity on Si/SiO₂/(Cr,Ti) before any visible failure (e.g., SEM)

Built a custom HT holder and ran in‑situ XRR + XRD at 175 °C to monitor thin‑film evolution over time.

XRR signatures consistent with effective multilayer restructuring (not just “same film getting rougher”).

Provides integrity evidence to select adhesion layer (Ti, Cr, or none) for Ag‑coated Si wafers from vendors.

50-nm Ag thin-film evolution over time as a function of adhesion layers

None

Cr

Ti

*Custom HT holder: CAD design + thermal FEA + sensor‑based calibration