In situ nanomechanics of GaN nanowires.

The deformation, fracture mechanisms, and the fracture strength of individual GaN nanowires were measured in real time using a transmission electron microscope-scanning probe microscope (TEM-SPM) platform. Surface mediated plasticity, such as dislocation nucleation from a free surface and plastic deformation between the SPM probe (the punch) and the nanowire contact surface were observed in situ. Although local plasticity was observed frequently, global plasticity was not observed, indicating the overall brittle nature of this material. Dislocation nucleation and propagation is a precursor before the fracture event, but the fracture surface shows brittle characteristic. The fracture surface is not straight but kinked at (10-10) or (10-11) planes. Dislocations are generated at a stress near the fracture strength of the nanowire, which ranges from 0.21 to 1.76 GPa. The results assess the mechanical properties of GaN nanowires and may provide important insight into the design of GaN nanowire devices for electronic and optoelectronic applications.

[1]  W. Cai,et al.  Size and temperature effects on the fracture mechanisms of silicon nanowires: Molecular dynamics simulations , 2010 .

[2]  D. Dimiduk,et al.  Sample Dimensions Influence Strength and Crystal Plasticity , 2004, Science.

[3]  Peter J. Pauzauskie,et al.  Crystallographic alignment of high-density gallium nitride nanowire arrays , 2004, Nature materials.

[4]  James S. Speck,et al.  Role of threading dislocation structure on the x‐ray diffraction peak widths in epitaxial GaN films , 1996 .

[5]  Charles M. Lieber,et al.  Gallium Nitride Nanowire Nanodevices , 2002 .

[6]  Xiangfeng Duan,et al.  Laser-Assisted Catalytic Growth of Single Crystal GaN Nanowires , 2000 .

[7]  James S. Speck,et al.  Defect structure of metal‐organic chemical vapor deposition‐grown epitaxial (0001) GaN/Al2O3 , 1996 .

[8]  S. Nakamura,et al.  Candela‐class high‐brightness InGaN/AlGaN double‐heterostructure blue‐light‐emitting diodes , 1994 .

[9]  George T. Wang,et al.  Correlation of growth temperature, photoluminescence, and resistivity in GaN nanowires , 2008 .

[10]  Charles M. Lieber,et al.  Nanobeam Mechanics: Elasticity, Strength, and Toughness of Nanorods and Nanotubes , 1997 .

[11]  S. Nakamura,et al.  InGaN-Based Multi-Quantum-Well-Structure Laser Diodes , 1996 .

[12]  Guosheng Cheng,et al.  Large-scale synthesis of single crystalline gallium nitride nanowires , 1999 .

[13]  Keon Wook Kang,et al.  Brittle and ductile fracture of semiconductor nanowires – molecular dynamics simulations , 2007 .

[14]  A. Minor,et al.  A new view of the onset of plasticity during the nanoindentation of aluminium , 2006, Nature materials.

[15]  Andrew M Minor,et al.  Mechanical annealing and source-limited deformation in submicrometre-diameter Ni crystals. , 2008, Nature materials.

[16]  A. Minor,et al.  Superglide at an internal incommensurate boundary. , 2010, Nano letters.

[17]  Heon-Jin Choi,et al.  Single-crystal gallium nitride nanotubes , 2003, Nature.

[18]  J. Greer,et al.  Nanoscale gold pillars strengthened through dislocation starvation , 2006 .

[19]  S. Hersee,et al.  The controlled growth of GaN nanowires. , 2006, Nano letters.

[20]  Stephane Evoy,et al.  Diameter-dependent electromechanical properties of GaN nanowires. , 2006, Nano letters.

[21]  A. Alec Talin,et al.  Three-Dimensional Visualization of Surface Defects in Core-Shell Nanowires. , 2008 .

[22]  George T. Wang,et al.  Highly aligned, template-free growth and characterization of vertical GaN nanowires on sapphire by metal–organic chemical vapour deposition , 2006 .

[23]  H. Morkoç,et al.  Large‐band‐gap SiC, III‐V nitride, and II‐VI ZnSe‐based semiconductor device technologies , 1994 .

[24]  H. Morkoç,et al.  GaN, AlN, and InN: A review , 1992 .

[25]  C. A. Volkert,et al.  Size effects in the deformation of sub-micron Au columns , 2006 .

[26]  Elaine Lai,et al.  Photoluminescence, thermal transport, and breakdown in joule-heated GaN nanowires. , 2009, Nano letters.

[27]  Joshua E. Goldberger,et al.  SEMICONDUCTOR NANOWIRES AND NANOTUBES , 2004 .

[28]  J. Fischer,et al.  Defects in GaN Nanowires , 2006 .

[29]  Kelly P. Knutsen,et al.  Single gallium nitride nanowire lasers , 2002, Nature materials.

[30]  Kun Zheng,et al.  Electron-beam-assisted superplastic shaping of nanoscale amorphous silica , 2010, Nature communications.

[31]  Ting Zhu,et al.  Ultra-strength materials , 2010 .

[32]  J.Y. Tsao,et al.  Solid-state lighting: lamps, chips and materials for tomorrow , 2005, (CLEO). Conference on Lasers and Electro-Optics, 2005..

[33]  Michael N. Fairchild,et al.  GaN nanowire light emitting diodes based on templated and scalable nanowire growth , 2009 .

[34]  Charles M. Lieber,et al.  Synthesis of p-Type Gallium Nitride Nanowires for Electronic and Photonic Nanodevices , 2003 .