Ultralow-k dielectrics are mainly porous and pose reliability issues as copper barrier integrity is compromised on porous surfaces. No work is reported on use of self-assembled monolayers ͑SAMs͒ as Cu diffusion barrier or to seal pores for ultralow-k dielectrics. We attached SAMs to ultralow-k film and confirmed by analytical techniques such as Auger and X-ray photoelectron spectroscopic analysis. We report reduction of leakage current and enhancement of dielectric breakdown voltage of the ultralow-k p-SiLK film after SAM attachment showing it to be a promising barrier material for prevention of Cu diffusion. H 2 /N 2 plasma treated p-SiLK film showed early breakdown and high leakage in spite of SAM attachment. .As the feature size further shrinks for 65 nm and below technology nodes for advanced Cu interconnects, ultrathin-barrier layers are needed and further improvement of step coverage is necessary. In the efforts to prevent Cu diffusion, it becomes challenging to meet the requirements of realizing sub-10 nm barrier layers. An alternative approach of self-assembled monolayers ͑SAMs͒ as barrier layers has been recently explored and studied. 1 The main advantage of the SAM is its "near zero" thickness which is just one molecular length. This is attractive for future technologies that will require nano-sized interconnects. 2 The molecules of SAM are composed of three parts, the terminal functional group, the alkyl chain, and the anchor group. SAMs are typically attached to a substrate on one end by moieties such as a thiol ͑-SH͒ anchor groups. The other end is usually comprised of a silane ͑-SiX3͒ where X is typically a halogen or an alkoxy group͒. The feasibility of employing SAM as a diffusion barrier for Cu/oxide interconnects was first reported by Ramanath et al. 3 All subsequent studies by other researchers reported the diffusion barrier property of SAM coated on SiO 2 with dielectric constant k = ϳ 4. No report is found for the effect of SAM on new generation materials such as ultralow-k dielectrics, which are being used to further reduce the interconnect RC delay.In this study, we have used a porous ultralow-k material namely p-SiLK ͑from The Dow Chemical͒ which is an aromatic carbon rich organic polymer, with a k value of 2.2. 4 The low dielectric constant in this material is achieved by introducing nano-pores into the bulk. Porosity related issues such as moisture or solvent absorption, enhanced Cu diffusion, and poor barrier integrity are huge concerns in Cu damascene process integration. Many methods have been tried to seal the pores, one such is to deposit by physical vapor deposition of an ultrathin dielectric layer as barrier to prevent Cu diffusion. 5 In this case, there is no chemical bonding between the dielectric and Cu. SAM is a single molecule of length ϳ20 Å, thereby satisfying thickness requirements and is attached to both Cu and dielectric by chemical bonds. The formation of chemical bond could in turn help to improve dielectric and metallization reliability.The p-SiLK material was spun o...

Diabetes affects 6% of the national population, yet approximately 50% of persons with diabetes remain undiagnosed and receive no treatment. In specific populations, Acanthosis Nigricans (AN) may serve as an early clinical proxy marker of increased risk of type II diabetes. The results of this pilot project to screen selected school age students in New Mexico for AN indicate that a large number of these students may be at increased risk for developing type II diabetes as young adults. The future burden of diabetes on individuals, families, communities, and health care systems may be greater than previously recognized.

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We discuss several mechanistic approaches and experimental data for improving post-CMP cleaning of W plugs with TiN as barrier liner, and dielectric substrates SiO2 and Si3N4 for use at the 10 nm technology node (metal pitch of 40 nm). Particle charge in the low pH, W CMP slurries are usually positive, and the W surface is always negatively charged at pH >3. Therefore, a strong electrostatic attraction is expected to occur between the W surface and the residual particles during post-CMP cleaning. Two main approaches were chosen to break down the strong particles-W surface post-CMP electrostatic interactions, as well as particles dispersion and prevention of redeposition: (1) using cleaning additives able to adsorb at the W surface and reverse the W surface charge; (2) using organic additives to reverse the particle charge. The latter approach results in two strongly negative charged surfaces, which are able to repulse each other, and leads to the best cleaning.