Proceedings Article | 8 May 2012
Proc. SPIE. 8373, Micro- and Nanotechnology Sensors, Systems, and Applications IV
KEYWORDS: Nanostructures, Etching, Ions, Chemistry, Gallium nitride, Photomasks, Plasma etching, Nanolithography, Plasma, Anisotropy
We report the systematic etching profile of GaN nano pillar structures using inductively coupled plasma (ICP) etching
techniques. We were able to control the side wall angle, shape and dimension of such nanoscale structures by carefully
selecting the etching parameters. We present the effects of variations of the etch parameters, such as ICP power, RF
power, chamber pressure, and substrate temperature on the etch characteristics, such as etch rate, sidewall angle,
anisotropy, mask erosion, and surface roughness. Utilizing such methods, we demonstrated the fabrication of nanoscale
structures with designed shapes and dimensions over large area. Nanocolumns with diameter of 120 nm and height of
1.6 μm with sidewall angle of 86° (90° represent a vertical sidewall) were fabricated. Nanocones with tip diameter of 30
nm and height of 1.6 μm with sidewall angle of 70° were demonstrated. The structures produced by such top-down
method could potentially be used in light-emitting diodes, laser diodes, photodetectors, vertical transistors, fieldemitters,
and photovoltaic devices.
