20079
In this Review article , the unique role of SAMs acting as either active or auxiliary layers in carbon nanomaterials - based field - effect transistors is highlighted for tuning the substrate effect , controlling the carrier type and density in the conducting channel , and even installing new functionalities .
 Chemical: carbon
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: carbon