Reaction mechanisms of thermal atomic oxygen interaction with organosilicate low k dielectric materials from ab initio molecular dynamics simulations

Abstract

Accurate combined-hyperbolic-inverse-power-representation of ab initio potential energy surface for the hydroperoxyl radical and dynamics study of O + OH reaction J. Chem. Phys. 138, 134117 (2013); 10.1063/1.4795826Reaction mechanisms of oxygen plasma interaction with organosilicate low-k materials containing organic crosslinking groups J. Vac. Sci. Technol. A 30, 061302 (2012); 10.1116/1.4755898 Ab initio simulations of oxygen atom insertion and substitutional doping of carbon nanotubesThe interactions of the oxidizing plasma with the low k dielectric materials and the associated damage mechanisms are of great technological interest for processing current and next generation low k materials. Density functional theory based ab initio molecular dynamics simulations have been performed to evaluate the reaction mechanisms of thermal atomic oxygen ͓in triplet ͑ 3 P͒ or singlet ͑ 1 D͒ state͔ with the organosilicate low k materials represented by model systems. The threshold kinetic energies of attacking atomic oxygen and the reaction pathway were found to be highly incident angle dependent. Carbon abstraction through methyl radical formation can happen at energy barriers as low as 0.1 eV when O radical attack occurs along the axes inclined to the Si-C bond. The simulation results agree well with recent experiments and support diffusion-controlled etching rate dependence, and dielectric constant increases due to oxygen plasma etching.

Organosilicate glass dielectric films with backbone carbon: Enhanced resistance to carbon loss in plasma environments

“…2). This reaction has been observed in various attack angles and energies [6]. Results thus suggest that methylene linkage in OSG can decrease carbon loss under oxygen plasma treatment, improving plasma damage resistance.…”

“…3 clearly demonstrate that backbone carbon groups exhibit a dramatically decreased loss rate in the presence of VUV+O 2 -the principal agent for carbon abstraction in typical O 2 plasma environments [8]. Additionally, AIMD simulations and XPS studies indicate that Si-CH 3 groups in the presence of O( 3 P) exhibit a concerted Si-C bond scission/Si-O bond formation mechanism which is highly dependent on the O trajectory [1,6]. This is in sharp contrast to AIMD results for Si-CH 2 -Si (Fig.…”

“…Ab initio molecular dynamics simulation (MDS) methods, based on density functional theory, have been described previously [1,6]. …”

“…4 shows the reactant and final states before/after atomic oxygen ( 3 P, 0.1 eV) collision reaction with TMCTS. By reacting with atomic oxygen and breaking the Si-C(H 2 -Si-) bond, the resulting methyl (Si-CH 2 ) groups are retained [6]. As a result, there is no carbon removal.…”

Influence of O(3P)/O2 Flux on the Atomic Layer Deposition of B2O3 Using Trimethyl Borate at Room Temperature

“…60,62−64 Indeed, C abstraction from silicon carbide occurs readily in both low and high O( 3 P)/O 2 regimes, as seen in Figures 5a and 7a. 9,59 Although O( 3 P) radicals do not have sufficient energy for direct O−CH 3 bond scission, the likelihood of OCH 3 abstraction from a fivecoordinated BO 2 (OCH 3 ) 3 cannot be ruled out.…”