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A new polysilicon grain engineering technology for the improvement of over erase in 0.18-[micro]m floating-gate flash memory has been developed with the use of single-wafer polysilicon processing, which makes it practical to use hydrogen as a process variable. The addition of hydrogen in polysilicon deposition significantly alters the reaction kinetics and produces polysilicon thin film of smooth surface, fine and uniformly distributed grains. Such a micrograin polysilicon possesses show excellent high-temperature stability. The benefits of the micrograin polysilicon are to be demonstrated through its improvement in over erase of a 0.18-[micro]m floating-gate flash memory. Index Terms--Flash memory, grain size, over erase, polysilicon, single-wafer.

Advanced Chemical-mechanical polishing (CMP) process not only needs to maintain stable run-to-run thickness control but also achieve better within wafer/within chip planarization performance. Furthermore, slurries or other consumable parts, like PAD and Disks selection are also the keys for CMP process optimization. The most difficult thing in CMP process is to have capability to predict and cover the various topologies and layout densities patterned wafers and preventing the hot spots occurrences. In this study, different Neural-Network algorithm with data pre-processing models are implemented to the in-line CMP CLC tuning and dishing/erosion prediction at various topology/pattern density test vehicle pattern wafers. Transfer learning technique is implemented on the original Neural -Network algorithm model, the behavior of real product can be simulated and predicted based on the knowledge of test vehicle database successfully. With the aid of multiple layer erosion/ dishing Neural-Network algorithm model prediction, the potential high risky hot spots can be highlighted at the initial layout design stage, then further shorten the turn-around time of design layout validation. [ABSTRACT FROM AUTHOR]

Abstract: Sequential flow chemical vapor deposition (SFCVD), utilizing TiCl4/NH3 as reactants and immediate NH3 treatment after film deposition, is applied to produce TiN barrier films in the contact process. Secondary ion mass spectroscopy results indicate that the SFCVD TiN film can effectively block the diffusion of WF6 into the underlying Ti layer during W deposition. NH3 treatment immediately after film deposition causes SFCVD TiN films to be less contaminated with carbon than TiN films that are formed by metallic organic compounds chemical vapor deposition (MOCVD) and to contain less chlorine residue than conventional TiCl4/NH3 CVD TiN layers even at a low reaction temperature. According to the resistance measurement of Kelvin contacts, the SFCVD process yields a lower resistance and a more uniform distribution than the MOCVD or CVD process. Transmission electron microscopic observations demonstrate that WF6 can diffuse through the MOCVD TiN to react with the underlying Ti layer, causing a rupture at the Ti/TiN interface and poor W adhesion. The SFCVD TiN can serve as a sufficient diffusion barrier against WF6 penetration during W CVD deposition. [Copyright &y& Elsevier]

Abstract: Thermal stability of titanium and cobalt silicides were enhanced by implementing nitrogen or argon implantation prior to silicide formation. Silicide formed on N2 or Ar implanted blanket wafers, P-type, or N-type poly-silicon had better thermal stability as compared with non-implant ones. Furthermore, Ar implanted approach demonstrated superior thermal stability characteristics even in a RTP test of 1000°C/180s. With the aid of N2 or Ar implantation, the grain growth of the silicide under high temperature was suppressed and thus it prohibited further diffusion and redistribution of the metal. [Copyright &y& Elsevier]