Process control monitors for single-walled carbon nanotube based sensor fabrication processes

A novel ex-situ process control monitor (PCM) framework for sensor fabrication processes based on individual single-walled carbon nanotube (SWNT) transistors is presented. PCMs are designed, fabricated and evaluated to estimate the length and density of SWNTs in a typical sensor fabrication process through electrical measurements. We also show that the PCM structures are able to detect variations in SWNT density. The estimates are independently verified through atomic force microscopy and scanning electron microscopy measurements.