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Modification of chemical vapor deposition low-k films upon sequential exposure to helium plasma and then ammonia plasma is characterized using various methods. The He plasma emits extreme ultraviolet ͑EUV͒ photons creating O 2 vacancies, which impacts surface reactive sites and induces localized chemical modifications in the first surface monolayers. The subsequent NH 3 plasma treatment provides complete sealing of the low-k surface. The depth of the modification, which is a factor of merit of the sealing process, is limited because of the high absorption coefficient of silica-based low-k materials in the range of EUV emission.Integration of porous low dielectric constant ͑low-k͒ materials is a continuing issue in microelectronics industry. One of the most difficult challenges is related to the high sensitivity of porous materials to chemicals and plasma. Pores and their connectivity significantly increase the penetration depth of active species during different technological processes such as plasma etching and cleaning, deposition of barrier layers, chemical mechanical polishing ͑CMP͒, etc. The most severe damage of low-k materials happens during their exposure to strip-cleaning plasmas containing oxygen and hydrogen radicals. These radicals remove the carbon containing hydrophobic groups from the low-k materials. As a result of the carbon depletion, the films become hydrophilic. 1,2 Subsequent moisture absorption in the pores significantly increases the k value because of the high polarizability of water molecules.Recently, we have applied a diffusion-recombination model ͑Thiele analysis͒ to predict and quantify the plasma damage of porous low-k materials. 3 The penetration depth of radicals into porous low-k materials and the depth of plasma damage depend on the Thiele modulus, , defined as follows ͑Eq. 1͒where k r is the sum of reaction constants consuming active radicals on pore wall. D A and d p are diffusion coefficient and pore diameter, respectively. The higher the Thiele modulus, the lower the depth of penetration of active radicals. Because k r is mainly defined by the recombination of active radicals, the depth of plasma damage can be significantly reduced by stimulating the surface recombination of active radicals. The creation of surface active centers initiates the recombination of oxygen and hydrogen radicals and reduces the plasma damage. As an example, we showed that treatment of low-k materials in He plasma significantly reduces plasma low-k damage during the subsequent exposure to strip and cleaning plasmas. It was speculated that extreme ultraviolet ͑EUV͒ emission from He plasma creates chemically active sites on a low-k surface, which stimulate the recombination of active radicals in the surface area. In certain cases the activated surface area can stimulate and induce localized chemical reactions results in the sealing of low-k materials.In this work, the modification of the top part of low-k films treated by He and NH 3 plasmas is characterized by various methods. This plasma is normally ...

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Ru thin films were deposited by plasma enhanced atomic layer deposition using MethylCyclopentadienylPyrrolylRuthenium (MeCpPy)Ru and N 2 /NH 3 plasma. The growth characteristics have been studied on titanium nitride or tantalum nitride substrates of various thicknesses. On SiO 2 , a large incubation period has been observed, which can be resolved by the use of a metal nitride layer of $ 0.8 nm. The growth characteristics of Ru layers deposited on ultrathin metal nitride layers are similar to those on thick metal nitride substrates despite the fact that the metal nitride layers are not fully closed. Scaled Ru/metal nitride stacks were deposited in narrow lines down to 25 nm width. Thinning of the metal nitride does not impact the conformality of the Ru layer in the narrow lines. For the thinnest lines the Ru deposited on the side wall showed a more granular structure when compared to the bottom of the trench, which is attributed to the plasma directionality during the deposition process.