Development of Photon-Counting Laser-Light-Scattering Method for Detection of Nano-Particles Formed in CVD Plasmas

Abstract

A high sensitive photon-counting laser-light-scattering method for detection of nano-particles formed in CVDplasmas is developed to get information on nucleation and subsequent initial growth phase of particles. Size ofparticles is deduced from their diffusion after turning off discharge and their density is obtained using the sizeand absolute light scattering intensity. Using the developed method, we demonstrate detection of smallparticles down to a few nm in size and find the corresponding particle density is a high value of about 10¹¹cm^-3 even in low pressure silane RF discharges of low RF power, which are commonly used to deposit highquality thin films.