We have prepared the Li-rich layered NMC composite cathode material of the composition 0.3Li 2 MnO 3 0.7LiMn 0.33 Ni 0.33 Co 0.33 O 2 , (NMC) with 5 wt% Na doping. The latter material with composition of 0.3Li 2 MnO 3 .0.7Li 0.97 Na 0.03 Mn 0.33 Ni 0.33 Co 0.33 O 2 , synthesized as 200-300 nm size particles, was compared to its counterpart without Na. The discharge rate capability of the Li-rich NMC was greatly improved at both room temperature and 50 • C with the Na doping. The Na doped material exhibited significantly higher conductivity than its un-doped analog as evidenced by dc electronic conductivity data and impedance of Li cells. Charge/discharge cycling results of Li cells at 50 • C indicated that the voltage decay of Li-rich NMC accompanied by a layer to spinel structural conversion was mitigated with Na doping. XRD analysis revealed that ionic exchange of Na occurs upon contact of the cathode material with the electrolyte and produces a volume expansion of the crystal lattice which triggers a favorable metal (probably Ni) migration to Li depleted regions during oxidation of Li 2 MnO 3 in the first cycle. XANES data showed that Na doped NMC has better Ni reduction efficiency to provide higher rate capability. EXAFS data supported this conclusion by showing that in the case of Na doped NMC, the structure has larger crystal cage allowing for better metal migration into the Li depleted regions located in the layered unit cell of C2/m space group. XANES of Mn K-edge supported by pre-edge analysis also revealed that during charging of the electrode, the Na doped NMC was oxidized to a higher Mn valence state compared to its undoped counterpart.

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A highly scalable approach for producing surface‐enhanced Raman spectroscopy substrates is introduced. The novel method involves assembling individual nanoparticles in pre‐defined templates, one particle per template, forming a high denisity of nanogaps over large areas, while decoupling nanostructure synthesis from placement.

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We introduce a nanoplasmonic platform merging multiple modalities for optical trapping, nanospectroscopy, and biosensing applications. Our platform is based on surface plasmon polariton driven monopole antenna arrays combining complementary strengths of localized and extended surface plasmons. Tailoring of spectrally narrow resonances lead to large index sensitivities ͑S ϳ 675 nm/ RIU͒ with record high figure of merits ͑FOMϳ 112.5͒. These monopole antennas supporting strong light localization with easily accessible near-field enhanced hotspots are suitable for vibrational nanospectroscopy and optical trapping. Strong optical forces ͑350 pN/ W / m 2 ͒ are shown at these hotspots enabling directional control with incident light polarization.

Chemical mechanical polishing (CMP) is considered as the paradigm shift that enabled optical photolithography to continue down to 0.12 m. Currently, the polishing physics is not well defined though it is known that the nature of the process makes particle removal after CMP difficult and necessary. It is important to understand the particle adhesion mechanisms resulting from the polishing process and the effect of the adhering force on particle removal in post-CMP cleaning processes. In this paper, strong particle adhesion is shown to be caused by chemical reactions (after initial hydrogen bonding) that take place in the presence of moisture and long aging time. In particle removal using brush cleaning, contact between the particle and the brush is essential to the removal of submicron particles. In noncontact mode, 0.1-m particle can hardly be removed when the brush is more than 1 maway from the particle. While in full contact mode, removal is possible for a 0.1-m particle at the investigated brush rotational speeds. The experimental data shows that high removal efficiency (low number of defects) is possible with a high brush pressure and a short cleaning time.

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A new model including the effects of polishing pressure and platen speed on particle penetration depth in chemical mechanical polishing (CMP) processes is derived based on the particle adhesion theory, the surface plastic deformation, and the pad-wafer partial contact. The predicted particle penetration depth is in good agreement with the experimental surface roughness data. Particle removal models in the final polishing and mechanical brushing/cleaning processes are proposed, and the removal forces are evaluated. The lift force in the hydrodynamic boundary layer is too small to lift particles off the surface and particles most likely roll off the surfaces by the drag force plus the contact forces from the pad or brush asperities. The effects of pressure, rotation speed, pad hardness, and chemical addition in post-CMP are also addressed.