Enhanced growth of device-quality copper by hydrogen plasma-assisted chemical vapor deposition

• Published in: Applied physics letters 1992-06, Vol.60 (25), p.3126-3128
• Main Authors: EISENBRAUN, E. T, BO ZHENG, DUNDON, C. P, PEI JUN DING, KALOYEROS, A. E
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Metals. Metallurgy; Physics; Solid surfaces and solid-solid interfaces; Surface and interface dynamics and vibrations; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.106773

A hydrogen plasma-assisted chemical vapor deposition (PACVD) process has been developed for the growth of device-quality copper films on large-area substrates. The process takes advantage of the high concentration of reactive hydrogen species present in the low-power plasma to enhance the clean reduction of copper β-diketonate precursors such as bis(hexafluoroacetylacetonato)copper(II). Copper films were produced at substrate temperatures of 160–170 °C, reactor working pressures of 1.3–1.7 Torr, hydrogen flow rates between 700 and 1200 cc/min, and hydrogen plasma power ranging from 15 to 30 W (with an equivalent power density of ∼0.10–0.25 W/cm2. The films were characterized by x-ray photoelectron spectroscopy, Rutherford backscattering spectroscopy, scanning electron microscopy (SEM), and cross-section SEM. These studies indicate that PACVD processes pure, dense, highly uniform films, and allows conformal step coverage and complete hole filling of patterned test structures. Growth rates over large-area substrates were as high as 1000 Å/min.