We report the synthesis of pentagonal- and hexagonal-shaped gold nanoparticles with controlled diameters ranging from 5 to 50 nm. These nanoparticles were prepared by a seeding growth approach. Sodium dodecyl sulfate (SDS) molecules served as the capping agent to restrict the particle size. In addition, the formation of highly faceted gold nanoparticles may be facilitated by the possibly ineffective capping interactions between the lamellar micellar structures formed by the SDS molecules and the gold nanoparticles. The crystal structure of the highly faceted particles was found to consist of mostly [111] surfaces as particle size increases, as revealed by both TEM and XRD results.

The growth of titanium silicide was investigated in sub-monolayer Ti deposited on Si(111)-7×7. The formation of nanorod and cluster structures was observed for 600 and 700°C deposited samples. In samples heated to 800°C, titanium silicide structures transformed to clusters. C49-TiSi2 nanorods were found to orient along three equivalent Si<220> directions with C49-TiSi2(200)∥Si(220). Deposition of sub-monolayer Ti at a high temperature was found to contribute to the lowering of the formation temperature of C49-TiSi2. The lowering of C49-TiSi2 growth temperature on heated substrate is attributed to smaller lattice mismatch between C49-TiSi2(200) and Si(220).

The impact of aluminum (Al) implantation into TiN/HfO 2 /SiO 2 on the effective work function is investigated. Al implanted through poly-Si cannot attain sufficient flatband voltage (V FB ) shift unless at higher implantation energy. Al implanted through TiN at 1.2 keV with a dose of 5 × 10 15 cm −2 raised the V FB to about 250 mV compared with a nonimplanted gate stack. Moreover, the V FB shift can be up to about 800 mV at 2 keV with the same dose level accompanied with slightly equivalent oxide thickness penalty and gate leakage current degradation. Optimized process window to control Al diffusion depth was essential to minimize these impacts.Index Terms-Al Implant, effective work function (EWF), HfO 2 .

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