Table 1

Parameters used in each step of the annular milling process to fabricate GaAs needles with a reduced diameter along a large range
Step Inner diameter (nm) Outer diameter (nm) Current (pA) Voltage (kV)
1 1,000 1,500 100 30
2 800 1,400 81 20
3 700 1,200 23 20
4 600 1,000 23 20
5 500 850 23 20
6 400 700 4 20
7 300 600 4 20
8 150 400 4 20
9 - - 70 5

The last step is to clean the amorphous layer around the needle.

Hernández-Saz et al.

Hern├índez-Saz et al. Nanoscale Research Letters 2012 7:681   doi:10.1186/1556-276X-7-681

Open Data