Fundamental Enabling Issues in Nanotechnology: Stress at the Atomic Scale

Technical Report · Mon Oct 01 04:00:00 EDT 2007

DOI:https://doi.org/10.2172/1324302· OSTI ID:1324302

Floro, Jerrold Anthony ^[1]; Foiles, Stephen Martin ^[2]; Hearne, Sean Joseph ^[2]; Hoyt, Jeffrey John ^[3]; Seel, Steven Craig ^[4]; Morales, Alfredo Martin ^[5]; Zimmerman, Jonathan A. ^[5]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Univ. of Virginia, Charlottesville, VA (United States). Dept. of Materials Science and Engineering
2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
3. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); McMaster Univ., Hamilton, ON (Canada)
4. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Emcore Corporation, Albuquerque, NM (United States)
5. Sandia National Lab. (SNL-CA), Livermore, CA (United States)

To effectively integrate nanotechnology into functional devices, fundamental aspects of material behavior at the nanometer scale must be understood. Stresses generated during thin film growth strongly influence component lifetime and performance; stress has also been proposed as a mechanism for stabilizing supported nanoscale structures. Yet the intrinsic connections between the evolving morphology of supported nanostructures and stress generation are still a matter of debate. This report presents results from a combined experiment and modeling approach to study stress evolution during thin film growth. Fully atomistic simulations are presented predicting stress generation mechanisms and magnitudes during all growth stages, from island nucleation to coalescence and film thickening. Simulations are validated by electrodeposition growth experiments, which establish the dependence of microstructure and growth stresses on process conditions and deposition geometry. Sandia is one of the few facilities with the resources to combine experiments and modeling/theory in this close a fashion. Experiments predicted an ongoing coalescence process that generates signficant tensile stress. Data from deposition experiments also support the existence of a kinetically limited compressive stress generation mechanism. Atomistic simulations explored island coalescence and deposition onto surfaces intersected by grain boundary structures to permit investigation of stress evolution during later growth stages, e.g., continual island coalescence and adatom incorporation into grain boundaries. The predictive capabilities of simulation permit direct determination of fundamental processes active in stress generation at the nanometer scale while connecting those processes, via new theory, to continuum models for much larger island and film structures. Our combined experiment and simulation results reveal the necessary materials science to tailor stress, and therefore performance, in nanostructures and, eventually, integrated nanocomponents.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sandia National Lab. (SNL-CA), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1324302
• Report Number(s): SAND2007--6689; 547367
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
COALESCENCE
ELECTRODEPOSITION
EVOLUTION
GEOMETRY
MORPHOLOGY
NANOSTRUCTURES
NANOTECHNOLOGY
NUCLEATION
SIMULATION
STRESSES
THIN FILMS