Abstract: Fourier Transform Infrared (FTIR) Spectroscopy has long been utilized as an analytical technique for qualitatively determining the presence of various different chemical bonds in gasses, liquids, solids, and on surfaces. Most recently, FTIR has been proven to be extremely useful for understanding the different types of bonding present in low dielectric constant “low-k” organosilicate materials. These low-k materials are predominantly utilized in the nanoelectronics industry as the interlayer dielectric material in advanced Cu interconnect structures. In this article, we utilize FTIR to perform a detailed analysis of the changes in chemical bonding that occur in Plasma Enhanced Chemically Vapor Deposited (PECVD) low-k a-SiC:H thin films. PECVD low-k a-SiC:H materials are equally important in advanced Cu interconnects and are utilized as both etch stop and Cu diffusion barrier layers. We specifically investigate the changes that occur in low-k a-SiC:H films as the dielectric constant and mass density of these films are decreased from > 7 to 3 respectively. We show that decreases in mass density and dielectric constant are accompanied by both an increase in terminal SiH x and CH x bonding and a decrease in Si C network bonding. At densities of 1.85 g/cm 3 , the concentration of terminal SiH x bonding peaks and subsequent hydrogen incorporation are achieved predominantly via terminal CH 3 groups. Low-k a-SiC:H films with k 3 can be achieved via incorporating larger organic phenyl groups but result in non-stoichiometric carbon rich films. Electron beam curing of these lower density a-SiC:H films results in volatilization of the phenyl groups leaving behind nanoporous regions and production of some C C C chain linkages in the network.

Abstract: Silicon nanowires (SiNWs) have recently been shown to be promising as high capacity lithium battery anodes. SiNWs can be grown with their long axis along several different crystallographicdirections.Duetodistinctatomicconfiguration and electronic structure of SiNWs with different axial orienta- tions, their lithium insertion behavior could be different. This paper focuses on the characteristics of single Li defects, includ- ing binding energy, diffusion barriers, and dependence on uniaxial strain in (110), (100), (111), and (112) SiNWs. Our systematic ab initio study suggests that the SiLi interaction is weaker when the SiLi bond direction is aligned close to the SiNW long axis. This results in the (110) and (111) SiNWs having the highest and lowest Li binding energy, respectively, and it makes the diffusionbarrieralongtheSiNWaxislowerthanotherpathways.Underexternalstrain,itwasfoundthat(110)and(001)SiNWsare the most and least sensitive, respectively. For diffusion along the axial direction, the barrier increases (decreases) under tension (compression). This feature results in a considerable difference in the magnitude of the energy barrier along different diffusion pathways.

Abstract: Conformal hermetic dielectric films suitable as dielectric diffusion barriers over 3D topography. In embodiments, the dielectric diffusion barrier includes a dielectric layer, such as a metal oxide, which can be deposited by atomic layer deposition (ALD) techniques with a conformality and density greater than can be achieved in a conventional silicon dioxide-based film deposited by a PECVD process for a thinner contiguous hermetic diffusion barrier. In further embodiments, the diffusion barrier is a multi-layered film including a high-k dielectric layer and a low-k or intermediate-k dielectric layer (e.g., a bi-layer) to reduce the dielectric constant of the diffusion barrier. In other embodiments a silicate of a high-k dielectric layer (e.g., a metal silicate) is formed to lower the k-value of the diffusion barrier by adjusting the silicon content of the silicate while maintaining high film conformality and density.

Abstract: Electrical and physical characteristics of the atomic layer deposited beryllium oxide (BeO) grown on the Si and GaAs substrates were evaluated as a barrier/passivation layer in the III-V devices. Compared to Al2O3, BeO exhibits lower interface defect density and hysteresis, and smaller frequency dispersion and leakage current density at the same effective oxide thickness, as well as an excellent self-cleaning effect. These dielectric characteristics combined with its advantageous intrinsic properties, such as high thermal stability, large energy band-gap(10.6 eV), effective diffusion barrier, and low intrinsic structural defects, make BeO an excellent candidate for the interfacial passivation layer applications in the channel III-V devices.

Abstract: A diffusion barrier layer of a few nanometers in thickness is required for a Cu/SiO2 interconnect structure for advanced integrated circuits (ICs). This paper reports a new barrier material and process by chemical vapor deposition (CVD) of a Mn oxide layer using a bis(ethylcyclopentadienyl)manganese precursor. A good adhesion was obtained when the MnOx layer was deposited below 300°C because of the small amount of carbon inclusion within the layer. The metal-oxide-semiconductor samples of Cu/MnOx/SiO2/p-Si showed a very low leakage current of less than 10-7 A/cm2 at 4 MV/cm and a negligible shift of the flat-band voltage after thermal annealing and bias temperature annealing. The obtained results indicated that the CVD-deposited MnOx is an excellent diffusion barrier layer for advanced ICs.

Abstract: An IC includes a substrate having a semiconductor top surface and a bottom surface, wherein the semiconductor top surface includes one or more active circuit components and a plurality of through silicon vias (TSVs) extending through the substrate. The plurality of TSVs include an outer dielectric liner. The dielectric liner includes at least one halogen or a Group 15 element metal gettering agent in an average concentration from 1 to 10 atomic %. A metal diffusion barrier layer is on the dielectric liner and a metal filler is on the metal barrier layer. The metal gettering agent getters metal filler that escapes the metal barrier layer.

Abstract: Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different film processing methods can yield similar microstructural features such as nanovoids and nanometer-sized La2Zr2O7 grains. Nanoporosity is a typical feature found in such films and the implications for the functionality of the films are investigated by a combination of scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) and quantitative electron tomography. Chemical solution based La2Zr2O7 films deposited on flexible Ni‐5 at.%W substrates with a {100}� 001� biaxial texture were prepared for an in-depth characterization. A sponge-like structure composed of nanometer-sized voids is revealed by high-angle annular dark-field scanning transmission electron microscopy in combination with electron tomography. A three-dimensional quantification of nanovoids in the La2Zr2O7 film is obtained on a local scale. Mostly non-interconnected highly faceted nanovoids compromise more than one-fifth of the investigated sample volume. The diffusion barrier efficiency of a 170 nm thick La2Zr2O7 film is investigated by STEM-EELS, yielding a 1.8 ± 0.2 nm oxide layer beyond which no significant nickel diffusion can be detected and intermixing is observed. This is of particular significance for the functionality of YBa2Cu3O7−δ coated conductor architectures based on solution derived La2Zr2O7 films as diffusion barriers. (Some figures in this article are in colour only in the electronic version)

Abstract: Synchrotron radiation photoelectron spectroscopy (SRPES) is used to investigate the in situ formation of ultra thin Mn silicate layers on SiO2, which has relevance for copper diffusion barrier layers in microelectronic devices. High temperature vacuum annealing of metallic Mn (∼1.5 nm) deposited on a 4 nm thermally grown SiO2 film results in the self limiting formation of a magnesium silicate layer, the stoichiometry of which is consistent with the formation of MnSiO3. Curve fitted Mn 3p SRPES spectra show no evidence for the presence of a manganese oxide phase at the Mn/SiO2 interface, in contrast to previous reports.

Abstract: Effects of the tensile strain on absorption and diffusion of hydrogen atoms on graphene have been studied by first-principles calculations. Our calculations suggested that there exists a barrier of 0.22 eV for H atom to diffuse from free space to graphene. The barrier originates from the transition of the hybridization of the H-binded carbon atom in graphene from sp2 to sp3, and is robust against the tensile strain. It was also found that, first, the in-plane diffusion of H atoms on graphene is unlikely to happen at low temperature due to the high barrier without or with strain, and second, the tensile strain along the armchair direction greatly decreases the out-plane diffusion barrier of H atoms, making it possible at low temperature. In particular, when the armchair strain is moderate (<10%), we found that the out-plane diffusion of H atoms likely to happen by diffusing through C-C bonds, and for relatively large armchair strain around 15%, the out-plane diffusion will happen though the center of the benzene ring.

Abstract: The present invention relates to a process for realizing a connecting structure in a semiconductor substrate, and the semiconductor substrate realized accordingly. The semiconductor substrate has at least a first surface, and is foreseen for a 3D integration with a second substrate along the first surface, wherein the 3D integration is subject to a lateral misalignment in at least one dimension having a misalignment value. This process includes growing a diffusion barrier structure for preventing diffusion of elements out of a conductive layer into the rest of the semiconductor substrate, wherein a first end surface, being the most outward surface of the diffusion barrier structure and being substantially parallel to the first surface, along a direction perpendicular to the first surface and going from the substrate toward the first surface, of the diffusion barrier structure can have a length, in the direction of the lateral misalignment, the length being dependent on the misalignment value, wherein the length of the diffusion barrier structure is chosen such that in a 3D integrated structure a diffusion of elements out of a conductive layer of the second substrate is prevented in the integrated state.

Abstract: While interfacial graphite formation and subsequent poor film adhesion is commonly reported for chemical vapor deposited hard carbon films on cobalt-based materials, we find the presence of O2 in the feedgas mixture to be useful in achieving adhesion on a CoCrMo alloy. Nucleation studies of surface structure before formation of fully coalesced hard carbon films reveal that O2 feedgas helps mask the catalytic effect of cobalt with carbon through early formation of chromium oxides and carbides. The chromium oxides, in particular, act as a diffusion barrier to cobalt, minimizing its migration to the surface where it would otherwise interact deleteriously with carbon to form graphite. When O2 is not used, graphitic soot forms and films delaminate readily upon cooling to room temperature. Continuous 1 μm-thick nanostructured carbon films grown with O2 remain adhered with measured hardness of 60 GPa and show stable, non-catastrophic circumferential micro-cracks near the edges of indent craters made using Rockwell indentation.

Abstract: Diffusion of silver inner-electrode occurred during sintering of commercial low temperature co-fired glass ceramic substrate made the dielectric surface become light yellow. The samples added with silicon oxide (SiO2) powder, however, maintained white color. Silicon-oxide powder was used to modified the sintering behavior and inhibit the silver ions diffusion for the LTCC ceramics. The alumina particles in the LTCC substrates could be regarded as the diffusion barrier of silver ions. The activation energy for silver ions diffusion in the LTCC substrates was 101 kJ/mol. When 5 wt% SiO2 powder was added into the LTCC substrate, the diffusion activation energy of silver ions became 145 kJ/mol. At sintering temperature of 1180 K, the diffusion coefficient of silver ion in the LTCC ceramic substrates with and without additional SiO2 were 8.88 × 10−13 cm2/s and 1.08 × 10−12 cm2/s, respectively.

Abstract: A tungsten barrier portion is employed in a replacement gate structure to block diffusion of material from a metal portion to a work function material portion The tungsten barrier portion effectively functions as a diffusion barrier layer between the metal portion and the work function material portion so that the composition of the work function material portion is unaffected by anneal and/or usage of the field effect transistor including the replacement gate structure Thus, the threshold voltage of the field effect transistor can remain stable throughout processing steps and usage in the field

Abstract: A double-layer (DL) NiCoCrAlY coating was coated onto a Hf-containing Ni-based superalloy DZ125. The bottom layer produced by plasma activated electron beam-physical vapor deposition (PA EB-PVD) was featured by coarse-grained equiaxed microstructure, which is different from the columnar microstructure of the top layer produced by EB-PVD. Oxidation resistance of the DL coating and a conventional single-layer (SL) NiCoCrAlY coating produced by EB-PVD was investigated at 1373 K. The DL coating exhibited an improved oxidation resistance as compared with the SL coating. The bottom layer in the DL coating effectively inhibited outward diffusion of refractory elements, such as Hf and W from the superalloy substrate. Oxidation and diffusion barrier mechanisms of the DL coating were also discussed.

Abstract: Manganese oxide formed by a chemical vapor deposition (CVD) method is a promising candidate for an ultrathin diffusion barrier layer in the interconnect structure of advanced semiconductor devices. This study placed emphasis on the adsorbed moisture in a hydrophilic SiO2 substrate and investigated the effects of the adsorbed moisture on the formation behavior, structure and composition of the CVD Mn oxide layer. The SiO2 substrates were preannealed at 150 to 500 °C for 1 h to control the type and amount of the residual adsorbed moisture. A Mn oxide layer was subsequently deposited by thermal CVD of bis(ethylcyclopentadienyl)Mn at 200 °C for 30 min. The Mn oxide layer deposited on an as-received substrate was composed of the bilayer of crystalline MnOx and amorphous MnSixOy. The Mn oxide layer deposited on a preannealed substrate was composed of the single layer of amorphous MnSixOy. The crystalline MnOx layer was formed by the reaction of the Mn precursor with physisorbed moisture on the as-received SiO2....

Abstract: To prevent Co diffusion from cemented carbides at high working temperatures, we fabricated CrTaN coatings by reactive direct current magnetron co-sputtering onto 6 wt.% cobalt cemented carbide substrates, to form diffusion barrier layers. The nitrogen flow ratio, N 2 /(Ar + N 2 ), during the sputtering process was set at 0.4. The deposition rates of CrTaN coatings varied from 23 to 27 nm/min. The CrTaN coatings crystallized into a columnar structure, without heating the substrates during the sputtering process and exhibited surface hardness and Young's modulus values of 16–27 and 211–383 GPa, respectively. The CrTaN coatings were annealed at 500 and 600 °C for 4 h in air to evaluate the oxidation resistance and diffusion barrier performance. We also investigated oxidation resistance of the CrTaN coatings under a 50 ppm O 2 –N 2 atmosphere, to assess the fabricated layers effectiveness as a protective coating for glass molding dies.

Abstract: Transition-edge sensor microcalorimeter arrays in compact geometries and large formats experience local heating from bias power and x-ray hits that must be dissipated in the frame. For devices on solid, non-perforated silicon substrates, we have introduced an underlying embedded copper heatsinking layer to enhance the ability of the frame to remove this heat. In particular, such a layer can mitigate thermal crosstalk between nearby pixels within the array. Further improvements in array performance, such as decreased magnetic field sensitivity and stray inductance, are possible by turning the heatsinking layer into a superconducting ground plane. In this presentation, we report on the development of heatsinking layers consisting of a 1-2 μm thick high-quality copper layer which is sandwiched between two thin refractory metal-based diffusion barriers. These diffusion barriers are designed to avoid copper migration into the surrounding material over time, especially during our high temperature TES fabrication process which takes place in excess of 400°C . A 0.3-0.5 μm thick PECVD SiO2 cover layer isolates the heatsinking layer from the detector circuit. We present first results on our attempt to tailor the materials forming the diffusion barrier to fabricate both well defined superconducting ground planes and non-superconducting layers with the desired barrier characteristics.