Cu CVD from Copper(II) Hexafluoroacetylacetonate: II . Laser‐Assisted Selective Area Deposition

Abstract

The laser-assisted chemical vapor deposition of copper onto thermal SiO~-overcoated Si wafers in a cold wall atmospheric pressure reactor, using Cu(hfa)2 in Ar/H 2 (10%), or argon as carrier/diluent is discussed. The substrate was biased thermally at 130~ in Ar/H2 or 200~ in Ar. A multiline (k = 488 to 514 nm) continuous wave 4 ~m focused spot diameter, 150 mW argon ion laser was used to heat the spot to a temperature at, or above, the required decomposition temperature, ->150~ in Ar/H2 and ->250~ in Ar. The steady-state temperature on the SiO2 prior to the beginning of deposition was estimated using a modified Lax model, since there is no convenient way of measuring it experimentally. Under the conditions employed, a maximum copper spot growth rate of 0.12 ~m/min was obtained at 0.095 W laser power. The laser-assisted growth rates in the present system can be predicted within a factor of two from the kinetic model of Ehrlich and Tsao. An incubation time which varies inversely with power, and with the composition of the carrier gas was observed on SIO2, due to the low absorption of the incident energy in the SiO2 at the small laser power used. Auger electron spectroscopy, of the copper deposits has shown small levels of carbon and oxygen. It is possible that the temperature at the center of the beam spot is greater than 400~ after copper begins to nucleate, and that the organic ligands undergo some fragmentation, or that some degree of oxidation and carbonaceous contamination occurs upon exposure to air when specimens are removed from the reactor. Using the described deposition methods, it should be possible to effect repair of broken copper lines on a microelectronic package in a minute or two.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 137.207.120.173 Downloaded on 2014-11-18 to IP

Phosphorescence and Structure of a Tetrameric Copper(I)−Amide Cluster

“…We have been interested in volatile copper complexes that also show photochemical activity, so that Cu deposition might be induced by light . Several studies of laser-induced Cu CVD have been reported. − However, these experiments have generally utilized high-energy laser sources, so that both photothermal (i.e via laser-induced heating of the substrate) and photochemical processes have been observed. We wished to take advantage of copper(I) complexes that possess well-defined low-energy excited states, which might react more cleanly with reducing carrier gases to produce pure Cu.…”

The Influence of Temperature and Concentration on Copper Deposition Kinetics in Supercritical Carbon Dioxide

“…An overall activation energy of 51.9 kJ/mol was calculated from the data. For MOCVD Cu deposition using Cu(hfac) 2 , activation energies between 75 kJ/mol -80 kJ/mol have been reported [11,12]. In those MOCVD studies, the surface reaction was assumed to be the rate-controlling step.…”

Preparation of thin copper films from the vapour phase of volatile copper(I) and copper(II) derivatives by the CVD method

“…236 A thorough refinement of the photochemical process modes for the deposition of films was required to overcome the difficulties noted above. 237,240 In a study devoted to the effect of laser power on the growth rate of copper films from Cu(HFA) 2 vapour, 241 the deposition rate was increased from 20 to 120 nm min 71 in a stream of an argon ± hydrogen mixture and from 4 to 27 nm min 71 in a stream of argon, but the SER of the films were not reported. It was noted that in the presence of ethanol under laser activation conditions, as in the usual thermolysis, the growth rate of copper films increased.…”