Formation and microstructure of thin Ti silicide films for advanced technologies
We report on the solid-state reaction of thin PVD Ti films with in-situ doped Si & SiGe alloys using a combination of in-situ x-ray diffraction, sheet resistance, laser light scattering measurements and ex-situ x-ray pole figure analysis. Thin Ti films or thin bilayer films (Ni/Ti or NiPt/Ti) are found to be much more aligned with the underlying substrates. Millisecond laser anneals also lead to the introduction of strong in-plane texture.
High performance 14nm SOI FinFET CMOS technology with 0.0174µm2 embedded DRAM and 15 levels of Cu metallization
We present a fully integrated 14nm CMOS technology featuring finFET architecture on an SOI substrate for a diverse set of SoC applications including HP server microprocessors and LP ASICs. This SOI finFET architecture is integrated with a 4th generation deep trench embedded DRAM to provide an ultra-dense (0.0174um2) memory solution for industry leading `scale-out' processor design. A broad range of Vts is enabled on chip through a unique dual workfunction process applied to both NFETs and PFETs. This enables simultaneous optimization of both lowVt (HP) and HiVt (LP) devices without reliance on problematic approaches like heavy doping or Lgate modulation to create Vt differentiation. The SOI finFET's excellent subthreshold behavior allows gate length scaling to the sub 20nm regime and superior low Vdd operation. This leads to a substantial (>35%) performance gain for Vdd ~0.8V compared to the HP 22nm planar predecessor technology. At the same time, the exceptional FE/BE reliability enables high Vdd (>1.1V) operation essential to the high single thread performance for processors intended for `scale-up' enterprise systems. A hierarchical BEOL with 15 levels of copper interconnect delivers both high performance wire-ability as well as effective power supply and clock distribution for very large >600mm2 SoCs.
Effect of superficial gas velocity on the particle temperature distribution in a fluidized bed with heat production
The heat transfer behavior of particles and gas in an olefin polymerization fluidized bed was numerically analyzed using an in-house developed 3-D computational fluid dynamics discrete element model (CFD-DEM). First the implementation of the model was verified by comparing simulation results with analytical results. A constant volumetric heat production rate was implemented in the particle energy equation to mimic the heat production due to the polymerization reaction. It was found that the probability density function (PDF) of the particle temperature becomes more homogeneous with increasing superficial gas velocity. Furthermore, instantaneous snapshots of the thermal driving force (the difference between the single particle temperature and bed-average gas temperature, Tp− ) for different heat production rates provide detailed insight in the particle temperature distribution inside the fluidized bed. The time- and bed-averaged particle convective heat transfer coefficient, which was calculated by Gunn׳s correlation, was found to be independent of the superficial gas velocity. This is explained by the fact that the relative velocity of gas and particles in the emulsion phase, where most of the particles and gas interact, is hardly influenced when increasing the gas superficial velocity. From the spatial distribution of Nusselt number, it becomes apparent that the high heat transfer regions are found in the wake of rising bubbles, whereas low heat transfer rates are found in the clouds of the bubbles.