Charge and charging of nanoparticles in a SiH4 rf-plasma

Plasma-produced nanoparticles are of interest for many applications. They have very specific properties that can vary greatly from those in the at. and bulk materials, including thermodn. properties, such as a reduced melting temp., and optical properties, such as blue-shifted blackbody radiation. Since a plasma is dominated by free electrons, charge related properties, like a reduced work function for electron attachment and increased work function for photo ionization, are of major importance. In situ detection of nanoparticles inside a plasma is difficult. Hence, indirect methods including changes in optical emission, plasma voltage and currents are used to study particle growth. Here, electron d. measurements in the plasma are presented using an ultrafast microwave resonance technique (time resoln. below 1 micro s). This technique allows studying the charge and charging kinetics of nanoparticles within the initial milliseconds of their growth.