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A study is conducted to show that the combination of thermal activation and ultraviolet radiation promotes a selective bonding rearrangement of the organosilicate glass matrix. The rearrangement includes a transition of the large angle Si-O-Si bonds towards the more stable small angle or 'network' configuration (~144 degree), as well as an increase in the degree of cross-linking of the matrix through condensation reactions and some minor loss of CH3 groups.

The diffusion of typical metal atomic layer deposition (ALD) precursors inside porous dielectric films is studied and how surface treatments can be used to efficiently prevent ALD coating inside the porous network of micro-and mesoporous dielectric substrates is investigated. Plasma treatments for surface densification and polymer deposition are used to seal the surface pores and provide a new starting surface for ALD growth.

The growth of tungsten nitride carbide (WNxCy) films obtained by atomic layer deposition using triethylboron, tungsten hexafluoride, and ammonia precursors is determined by the density and type of reactive sites. The film properties change as a function of thickness. On silicon dioxide and silicon carbide, growth is initially nonlinear such that the transient regimes are characterized by island formation, as evidenced by a parabolic tungsten growth curve extending to film thicknesses of up to 5 nm. Such films have low densities of ∼4–6 g cm-3 corresponding to only ∼30%–45% of the bulk density of ∼13.1 g cm-3 determined for a WN0.45C0.55 composition. X-ray reflectivity, thermal desorption, and elastic recoil detection spectroscopies reveal surface roughening and compositional and density differences close to the substrate surface. The offset from linear growth in the case of WNxCy films deposited on silicon dioxide is induced by the initial reaction of silanol and siloxane groups with triethylborane resulting in passivating ethylsilyl groups on the surface. A transient regime is not observed for WNxCy growth on hydrogen-terminated silicon with the initial growth being dominated by the reduction of tungsten hexafluoride to tungsten. On silicon nitride a short transient regime is observed relative to the carbide and oxide surfaces attributed to the enhanced binding of the triethylboron precursor. [ABSTRACT FROM AUTHOR]

On nanoscale laminate structures, the interface cannot be identified any longer as the separation between two films of bulk materials. The formation of the interface defines the final composition and structure of the laminate structure. As such, the characterization of the interface becomes an important challenge. In this work the nanoscale laminate structures were formed by atomic layer deposition (ALD) of tungsten nitride carbide and tantalum nitride thin films on dense dielectrics [silicon carbide and silicon oxide (SiO2)]. The laminates were studied using x-ray reflectivity. The starting substrate surface is a primary factor in determining the density of the ALD layer. Moreover, in some cases, electron-density perturbations are observed in the vicinity of the interfacial region. A characterization strategy, using a density contrast layer between the silicon substrate and the SiO2 dielectric is presented. Depending on the chemical nature of precursors and substrate, ALD processes can either form specific interfacial organization or induce dielectric modifications, in any case, leading to unexpected metal-dielectric interactions. [ABSTRACT FROM AUTHOR]

The growth of tungsten nitride carbide W[N.sub.x][C.sub.y] films obtained from layer deposition using triethylboron, tungsten hexafluoride, and ammonia precursors is determined by the density and type of reactive sites. A transient regime is not observed for W[N.sub.x][C.sub.y] growth on hydrogen-terminated silicon with the initial growth being dominated by the reduction of tungsten hexafluoride to tungsten.

The impact of material/process interactions on low temperature CVD-O3 low-k dielectric film properties are presented. The film under investigation is deposited following a three-step process consisting of a low temperature chemical vapor deposition (CVD), an ex situ high temperature cure in a controlled ambient and a plasma treatment to seal the porous surface of the dielectric. In this paper, the extent to which the air break exposure, the cure, the nature of the plasma and the substrate can affect the material properties is investigated. The influence of the resist stripping plasmas on the material sealing and the mechanical properties during integration is also discussed. Finally, the dielectric k-value as extracted from damascene structures using Raphael™ simulations is presented and discussed. [Copyright &y& Elsevier]

Abstract: A ternary WN x C y system was deposited in a thermal ALD (atomic layer deposition) reactor from ASM at 300°C in a process sequence using tungsten hexafluoride (WF6), triethyl borane (TEB) and ammonia (NH3) as precursors. The WC x layers were deposited by a novel ALD process at a process temperature of 250°C. The WN x layers were deposited at 375°C using bis(tert-butylimido)-bis-(dimethylamido)tungsten ( t BuN)2(Me2N)2W (imido–amido) and NH3 as precursors. WN x grows faster on plasma enhanced chemical vapor deposition (PECVD) oxide than WC x does on chemical oxide. WN x C y grows better on PECVD oxide than on thermal oxide, which is opposite of what is seen for WN x . In the case of the ternary WN x C y system, the scalability towards thinner layers and galvanic corrosion behavior are disadvantages for the incorporation of the layer into Cu interconnects. ALD WC x based barriers have a low resistivity, but galvanic corrosion in a model slurry solution of 15% peroxide (H2O2) is a potential problem. Higher resistivity values are determined for the binary WN x layers. WN x shows a constant composition and density throughout the layer. [Copyright &y& Elsevier]