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A novel method is presented for the atomic layer deposition (ALD) of palladium on a tetrasulfide self-assembled monolayer functionalized SiO 2 surface. Additionally, a novel reducing agent (glyoxylic acid) was used to remove the organic ligands from the chemisorbed palladium(II) hexafluoroacetylacetonate metallorganic. Glyoxylic acid is an effective reducing agent above 200 C, which is not optimal for palladium but it is effective enough to show proof-of-concept and deposit a Pd ªseedº layer. Palladium was also deposited on iridium at 80 C and 130 C via a hydrogen process or on the Pd seed layer at 80 C. The 60 Pd film grown on the tetrasulfide self-assembled monolayer (SAM) showed nearly random texture and higher carbon and fluorine contamination levels compared to the one grown on Ir. The 55 film grown on Ir at 80 C is highly (111) textured with a grain size of~60 , as shown by reflection high energy electron diffraction (RHEED). The higher contamination levels of the Pd film deposited on the tetrasulfide SAM, as measured by X-ray photoelectron spectroscopy (XPS), is attributed to the high temperatures needed to deposit the Pd seed layer. The higher deposition temperatures cause more dissociation of the hfac ligand and a higher metallorganic desorption rate. These equate to less Pd being deposited and with higher contamination levels.

A method is presented for the atomic layer deposition (ALD) of palladium using remote hydrogen plasma as the reducing source and agent. Palladium was deposited on iridium, tungsten and silicon at 80 C using a remote inductively coupled hydrogen plasma with palladium(II) hexafluoroacetylacetonate as the precursor. In the case of the Pd film grown on Ir, the carbon and fluorine content were significantly reduced compared to previous thermal ALD results. Use of remote plasma eliminated the noble metal substrate requirement needed for thermal ALD, enabling films to be grown on W and Si. Ultra-thin Pd films grown on W and Si possessed a nearly random texture from reflection high-energy electron diffraction (RHEED) measurements. Atomic force microscopy (AFM) images showed very different surface morphologies for the different substrates suggesting very different substrate film interactions. X-ray photoelectron spectroscopy (XPS) measurements indicate high quality Pd films for all substrates, suggesting the substrate temperature was low enough to prevent dissociation of the hfac ligand and adequate C and F scavenging by the atomic hydrogen. The remote hydrogen plasma source results in the loss of selectivity but growth is evident on every surface used including surfaces that do not react strongly with the Pd precursor and are not catalytic towards the dissociation of molecular hydrogen.

Porosity has been introduced in existing low-k interlayer dielectrics to further reduce their dielectric constant. It is desirable to deposit a metallic layer on top of the porous dielectric by chemical vapor deposition ͑CVD͒. However this presents the challenge of preventing the precursor from penetrating into the porous dielectric and depositing metal within this insulating layer. In the present paper a low-k CVD polymer capping ͑Molecular Caulking™͒ is deposited at room temperature onto the porous ultralow k dielectric methyl silsesquioxane. Experiments show that the Molecular Caulking prevents precursor penetration during subsequent metallorganic CVD. In addition, while the Molecular Caulking itself slightly penetrates into the methyl silsesquioxane, it does not appreciably increase surface roughness or film dielectric constant.In future gigascale integrated circuits ͑ICS͒ resistive-capacitive ͑RC͒ delay is an increasingly important issue. 1 Carbon-doped oxides and aromatic polymers are examples of materials being investigated to replace SiO 2 as the interlayer dielectric ͑ILD͒. 2 Both materials possess lower dielectric constants and will lower the contribution to RC delay. In order to reduce the dielectric constant further, it is generally accepted that the ILD will contain some amount of porosity. The introduction of porosity results in a number of other undesirable properties such as a reduction in mechanical strength and susceptibility to penetration of chemicals. Most importantly, during chemical vapor deposition ͑CVD͒ exposure of the porous dielectric to gaseous precursors that are expected to infiltrate an open pore film or even a closed pore film if the pore wall thickness in the nanoscale dimensions 3-6 cause degradation of film properties. CVD will typically have a reactive sticking coefficient much less than one in order to have good conformal coverage. Indeed, one way to reduce this penetration would be to increase the reactive sticking coefficient, e.g., by increasing the deposition temperature. However, this would reduce the conformality of the deposition. Clearly porosity and conformal CVD on high aspect ratio substrates are fundamentally at odds.Several methods have been studied recently to solve this problem. A recent review details some of the currently proposed strategies to seal porous dielectrics. 7 A new sealing layer, Molecular Caulking, is presented here. MC films are deposited by CVD at room temperature using a free radical polymerization process. Preliminary results are promising. The approach taken was to measure the new sealant's ability to prevent penetration of metal precursors ͑copper, cobalt͒ during CVD. The depth distribution of deposited metals were measured by Rutherford backscattering spectrometry ͑RBS͒. In addition, changes in the dielectric constant as a result of MC, were determined by metal insulator semiconductor ͑MIS͒ capacitance measurements. Deposited film thickness was determined by both ellipsometry and ion beam backscattering using the 5.75 MeV 4 He elastic nucle...

Commonly known in macroscale mechanics, buckling phenomena are now also encountered in the nanoscale world as revealed in today's cutting-edge fabrication of microelectronics. The description of nanoscale buckling requires precise dimensional and elastic moduli measurements, as well as a thorough understanding of the relationships between stresses in the system and the ensuing morphologies. Here, we analyze quantitatively the buckling mechanics of organosilicate fins that are capped with hard masks in the process of lithographic formation of deep interconnects. We propose an analytical model that quantitatively describes the morphologies of the buckled fins generated by residual stresses in the hard mask. Using measurements of mechanical properties and geometric characteristics, we have verified the predictions of the analytical model for structures with various degrees of buckling, thus putting forth a framework for guiding the design of future nanoscale interconnect architectures.