9458
For this purpose , almost hexagonally arranged nanopillars of fixed areal density ( 127 mu m ( - 2 ) ) and diameters ( 35 nm ) but varying heights ( 40 - 150 nm ) were fabricated on silicon .
 Chemical: silicon
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: silicon 
Answer:
 Chemical: silicon