Effect of the carrier gas flow rate on the microstructure evolution and the generation of the charged nanoparticles during silicon chemical vapor deposition

J Nanosci Nanotechnol. 2013 Oct;13(10):7127-30. doi: 10.1166/jnn.2013.7669.

Abstract

The generation of charged nanoparticles in the gas phase has been continually reported in many chemical vapor deposition processes. Charged silicon nanoparticles in the gas phase were measured using a differential mobility analyzer connected to an atmospheric-pressure chemical vapor deposition reactor at various nitrogen carrier gas flow rates (300-1000 standard cubic centimeter per minute) under typical conditions for silicon deposition at the reactor temperature of 900 degrees C. The carrier gas flow rate affected not only the growth behavior of nanostructures but also the number concentration and size distribution of both negatively and positively charged nanoparticles. As the carrier gas flow rate decreased, the growth behavior changed from films to nanowires, which grew without catalytic metal nanoparticles on a quartz substrate.