Ultraclean two-stage aerosol reactor for production of oxide-passivated silicon nanoparticles for novel memory devices

Silicon nanoparticle-based floating gate metal oxide semiconductor field ef fect devices are attractive candidates for terabit cm(-2) density nonvolati le memory applications. We have designed an ultraclean two-stage aerosol pr ocess reactor and 200 mm wafer deposition chamber in order to integrate Si/ SiO2 nanoparticles into memory devices. In the first stage, silicon nanopar ticles are synthesized by thermal decomposition of silane gas in a reactor that has been optimized to produce nonagglomerated nanoparticles at rates s ufficient for layer deposition. In the second stage, the silicon particles are passivated with thermal oxide that partly consumes the particle. This t wo-stage aerosol reactor has been integrated to a 200 mm silicon wafer depo sition chamber that is contained within a class 100 cleanroom environment. This entire reactor system conforms to rigorous cleanliness specifications such that we can control transition metal contamination to as good as 10(10 ) atoms cm(-2). The deposition chamber has been designed to produce a contr ollable particle density profile along a 200 mm wafer where particles are t hermophoretically deposited uniformly over three-quarters of the wafer. Thu s, we now have the capability to deposit controlled densities of oxide-pass ivated silicon nanoparticles onto 200 mm silicon wafers for production of s ilicon nanoparticle memory devices. (C) 2001 The Electrochemical Society.