Effect of surface chemistry on the quality factors of micromechanical resonators

Single monolayers of molecules were found to strongly affect the quality factors of MHz-range torsional silicon resonators. By changing a single monolayer of molecules on the surface of a 5-μm-wide, 250-nm-thick silicon resonator - less than 0.07% of the total mass - the quality factor of the resonator was increased by 70%. In contrast, the standard commercial coating, a thin layer of silicon oxide, dissipates at least 75% of the mechanical energy in similarly sized resonators. Since the relative importance of these surface chemical losses scales with the resonator's surface-to-volume ratio, the development of low-loss, stable surface chemistries will be important for the production of high-performance micro- and nano-mechanical devices.

[1]  J. A. Henry,et al.  Controlling energy dissipation and stability of micromechanical silicon resonators with self-assembled monolayers , 2004 .

[2]  V. Braginsky,et al.  Systems with Small Dissipation , 1986 .

[3]  Nathan S. Lewis,et al.  Comparison of the Electrical Properties and Chemical Stability of Crystalline Silicon(111) Surfaces Alkylated Using Grignard Reagents or Olefins with Lewis Acid Catalysts , 2003 .

[4]  David L. Allara,et al.  An Intrinsic Relationship between Molecular Structure in Self-Assembled n-Alkylsiloxane Monolayers and Deposition Temperature , 1994 .

[5]  M. Roukes,et al.  Ultimate limits to inertial mass sensing based upon nanoelectromechanical systems , 2003, physics/0309075.

[6]  Methyl monolayers suppress mechanical energy dissipation in micromechanical silicon resonators , 2004 .

[7]  N. Lewis,et al.  Preparation of air-stable, low recombination velocity Si(111) surfaces through alkyl termination , 2000 .

[8]  Masayoshi Esashi,et al.  Investigating surface stress: Surface loss in ultrathin single-crystal silicon cantilevers , 2001 .

[9]  Matthew R. Linford,et al.  Alkyl Monolayers on Silicon Prepared from 1-Alkenes and Hydrogen-Terminated Silicon , 1995 .

[10]  T. Kenny,et al.  Attonewton force detection using ultrathin silicon cantilevers , 1997 .

[11]  Y. Chabal,et al.  Chemical etching of vicinal Si(111): Dependence of the surface structure and the hydrogen termination on the pH of the etching solutions , 1991 .

[12]  S. Solares,et al.  Low-temperature STM images of methyl-terminated Si(111) surfaces. , 2005, The journal of physical chemistry. B.

[13]  Yu Wang,et al.  Understanding the effects of surface chemistry on Q: mechanical energy dissipation in alkyl-terminated (C1-C18) micromechanical silicon resonators. , 2007, The journal of physical chemistry. B.

[14]  N. C. MacDonald,et al.  Dissipation measurements of vacuum-operated single-crystal silicon microresonators , 1995 .

[15]  Parpia,et al.  Low temperature mechanical properties of boron-doped silicon. , 1992, Physical review letters.

[16]  Yu Wang,et al.  Surface chemical control of mechanical energy losses in micromachined silicon structures , 2003 .

[17]  W. H. Weinberg,et al.  Alkylation of Si Surfaces Using a Two-Step Halogenation/Grignard Route , 1996 .

[18]  M. Hines,et al.  Effect of Surface Chemistry on Mechanical Energy Dissipation: Silicon Oxidation Does Not Inherently Decrease the Quality Factor , 2008 .

[19]  L. Sekaric,et al.  Measurement of mechanical resonance and losses in nanometer scale silicon wires , 1999 .

[20]  P. Allongue,et al.  Insights into the Formation Mechanisms of Si−OR Monolayers from the Thermal Reactions of Alcohols and Aldehydes with Si(111)−H1 , 2000 .

[21]  Masayoshi Esashi,et al.  Surface effects and high quality factors in ultrathin single-crystal silicon cantilevers , 2000 .