trans-[(H(2)NCH(2)CH(2)C triple bond N)(dppe)(2)Ru(C triple bond C)(6)Ru(dppe)(2)(N triple bond CCH(2)CH(2)NH(2))][PF(6)](2), 2[PF(6)](2), a derivative of trans-[Cl(dppe)(2)Ru(C triple bond C)(6)Ru(dppe)(2)Cl] functionalized for binding to a silicon substrate, has been prepared and characterized spectroscopically, electrochemically, and with a solid state, single-crystal structure determination. Covalent binding via reaction of one amine group to a boron-doped, smooth Si-Cl substrate is verified by XPS measurements and surface electrochemistry. Vertical orientation is demonstrated by film thickness measurements. Synthesis of the 2[PF(6)](3) mixed-valence complex on the surface is established by electrochemical techniques. Measurement of the ac capacitance of the film at 1 MHz as a function of voltage across the film with a pulse-counter pulse technique demonstrates controlled electric field generation of the two stable mixed-valence forms differing in the spatial location of one electron, that is, switching. As compared to [trans-Ru(dppm)(2)(C triple bond CFc)(NCCH(2)CH(2)NH(2))][PF(6)][Cl], 1[PF(6)][Cl], the magnitude of the capacitance signal per complex observed on switching is shown to increase with increasing distance between the metal centers. Additional experiments on 1[X][Cl] show that the potential for switching 1[X][Cl] increases in the order [X](-) = [SO(3)CF(3)](-)< [PF(6)](-) < [Cl](-). A simple electrostatic model suggests that the smaller is the counterion, the greater is the perturbation of the metal sites and the larger is the barrier for switching.

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Abstract-We present an efficient and accurate method to characterize the physical thickness of ultrathin gate oxides (down to 25Å) and the effective polysilicon doping of advanced CMOS devices. The method is based on the model for Fowler-Nordheim (F-N) tunneling current across the gate oxide with correction in gate voltage to account for the polysilicon-gate depletion. By fitting the model to measured data, both the gate oxide thickness and the effective poly doping are unambiguously determined. Unlike the traditional capacitance-voltage (C0V ) technique that overestimates thin-oxide thickness and requires large area capacitor, this approach results in true physical thickness and the measurement can be performed on a standard sub-half micron transistor. The method is suitable for oxide thickness monitoring in manufacturing environments.

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N-Cbz and Boc protected spirocyclic dienes were prepared by dialkylation of cyclopentadiene. These dienes coupled efficiently in a series of iminonitroso Diels-Alder reactions to produce a series of new spirocyclic adducts. Hydrogenolysis of these adducts afforded new spirocycles that contain multiple handles for further functionalization. Furthermore, stereo-controlled dihydroxylation and reductive cleavage of the spirocyclic adducts generated versatile scaffolds for the syntheses and derivatization of novel spirocyclic carbocyclic nucleoside analogs.