Posts Tagged ‘ZnO’

Today I read paper by Xinwei Deng from University of Wisconsin-Madison titled “Applications of statistical
quantification techniques in nanomechanics and nanoelectronics”. You can download the paper from here.

In the paper Deng talks about the infeasibility of standard characterization methods in nanoscale. For example ordinary tensile strength test cannot be done at the nanoscale, because you material cannot be clamped by the holder without sliding.

Deng argues that statistical methods can be better alternative, and demonstrates his idea in two areas: nanomechanics and nanoelectronics.

Other two related papers are:

Statistical approach to quantifying the elastic deformation of nanomaterials

Quantifying the elastic deformation behavior of bridged nanobelts


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Today I read the paper “Optimizing and Improving the Growth Quality of ZnO Nanowire Arrays Guided by Statistical Design of Experiments“.

High aspect ratio of ZnO nanowires increases antireflectivity of photovoltaic devices. Xu et al. managed to increase aspet ratio from 10 to 23.

Firstly they made 34-2 factorial design. Tested parameters:

  • temperature of furnace
  • growth time
  • zinc concentration
  • capping agent

Some of the runs resulted in poor aspect ratios. Aspect ratio was calculated by measuring lengths and widths of around 20 nanowires using Photoshop. In the second stage they used this information to narrow down focus.

In the third stage they aimed at reducing noise effects (decreasing noise means getting consistent results in each trial with same parameter settings). After that, they had 3 more stages.

I liked the stage by stage refinement of parameters. Will be helpful for my research. What I did not like was aspect ratio calculation process: 20 nanowires is not enough, how they selected these 20 nanowires is not clear.

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