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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 sacrificial material deposited by CVD is used to demonstrate air gap formation in single damascene structures by UV-assisted decomposition. The material is removed through a porous low-k cap, after completion of the damascene scheme. The porosity of the low-k cap is shown to be critical for efficient air gap formation. Capacitance reduction of ∼50% is demonstrated using this technique compared to conventional SiOC(H) interconnects and an effective dielectric constant of 1.7 is extrapolated. [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]