Atmospheric Pressure Chemical Vapor Deposition of Copper Thin Films: I . Horizontal Hot Wall Reactor

Abstract

We have studied the reaction kinetics of Cu chemical vapor deposition (CVD) by reduction of in a horizontal flow, atmospheric pressure, hot‐wall CVD reactor. Using glass substrates, we can routinely deposit films at temperatures as low as 523 K and growth rates of 200 Å/min, with resistivities between 2–3 μΩ‐cm. The reactor is operated at integral conversions of , and the reaction kinetics are determined by analyzing the axial thickness profiles of the deposited films obtained under a series of different operating conditions (e.g. reactant composition, substrate temperature, and carrier gas flow rate). The steady‐state growth rate exhibits saturation kinetics with respect to concentration, positive reaction order with respect to , and negative reaction order with respect to H(hfa). We propose a mechanism based on dissociative adsorption of at vacant surface sites, followed by H‐atom assisted desorption of H(hfa) ligands as the rate limiting step in the overall reaction. The resulting rate expression is combined with a reactor model based on a one‐dimensional species conservation equation, and the calculated thickness profiles are compared with observed results to obtain estimates of the kinetic parameters.