From the paper http://scitation.aip.org/content/aip/journal/jap/117/3/10.1063/1.4905616 http://scitation.aip.org/content/aip/journal/jap/117/3/10.10... it appea

From the paper http://scitation.aip.org/content/aip/journal/jap/117/3/10.1063/1.4905616 http://scitation.aip.org/content/aip/journal/jap/117/3/10.10... it appears they have modeled the pattern after the lotus leaf http://en.wikipedia.org/wiki/Lotus_effect http://en.wikipedia.org/wiki/Lotus_effect