Film Growth Kinetics of Chemical Vapor Deposition of Copper from Cu (  HFA  ) 2

Abstract

Copper films have been grown by chemical vapor deposition (CVD) from copper (II) hexafluoroacetylacetonate, Cu(HFA)2, in a cold wall, vertical flow reactor with pure hydrogen and a mixture of hydrogen (75%)/argon (25%). The quantitatively measured operating conditions were 10 Torr total pressure,~ 300 to 400~ substrate temperature, and 70 to 85~ precursor temperature. Film growth rates were between 100 to 1000 A/min depending on processing conditions. The copper film growth rate was 0.5 order in both precursor and hydrogen concentration. A deposition temperature of about 300~ was needed to obtain significant film growth. Only surface impurities were detected in copper film. Any impurities below the surface were under the detection limits of Auger electron spectroscopy analysis. Resistivities of 2.0-3.0 ~t~ cm were routinely obtained. Two mechanisms are proposed for the growth of copper films by CVD using Cu(HFA)2 which are consistent with our experimental observations and those in the literature.

Experimental and computational investigation of chemical vapor deposition of Cu from Cu amidinate

“…Most common is the activation of volumetric reactions in the gas phase of the reactor due to the high temperatures [11] which causes the depletion of the reactants in the gas phase. Other possible reasons are the etching of the surface from a secondary material [25], increased desorption rate of the precursor [25] and inhibitions effects [21,26].…”

Phase stability and oxygen doping in the Cu–N–O system

“…Copper (II) hexafluoroacetylacetonate [Cu(1,1,1,5,5,5-hexafluoro-2,4 pentanedionate) 2 ] or Cu(hfac) 2 , which is a metalorganic (MO) precursor of the b-diketonate type with low sublimation temperature and high reactivity has been used as metal precursor. This precursor has been used earlier together with H 2 to deposit copper [23,24], with NH 3 to deposit copper nitride [25,26], with H 2 O to deposit copper (I) oxide [26] and with O 2 to deposit copper (II) oxide [27].…”

Mechanism of copper chemical vapor deposition from copper dipivaloylmethanate in hydrogen

“…Since the introduction of H(dpm) increases the low-temperature deposition rate in terms of film weight by a factor of 2-4, we believe that process (12) prevails over (4). Then, we have (13) By analogy with (11), we obtain…”

“…Gribov et al [12] proposed a mechanism of Cu(II) acetylacetonate, Cu(acac) 2 , decomposition via the formation of intermediate adsorbed radicals, [(acac) and , followed by [(acac) decomposition into Cu and . A more sophisticated mechanism of Cu(hfac) 2 decomposition in a hydrogen atmosphere, involving a large number of steps, was examined by Kim et al [13] and Borgharkar and Griffin [14]. Just as Lai et al [2], they considered stable adsorbed radicals resulting from the dissociative adsorption of Cu(hfac) 2 .…”