This work investigates the influence of electrode geometrical parameters on the electric-field-strength distribution required for the directed growth of horizontally aligned carbon nanotubes by plasma-enhanced chemical vapor deposition. Optimal electrode parameters that provide maximal electric field strength and high efficiency of aligned nanotube growth have been determined. The influence of electrode shape (rectangular, semicircular, and triangular) on the field-strength distribution and nanotube alignment is demonstrated. The results contribute to optimizing the growth process of horizontally aligned carbon nanotubes for applications in sensors and nanopiezotronic devices.