The effects of varying the yttrium (Y) level in a (TaC) 1Àx Y x gate electrode on the structural and electrical properties of a hafnium (Hf)-based high-k metal-oxide-semiconductor (MOS) capacitor, including flatband voltage (V fb ), were evaluated. The composition of (TaC) 1Àx Y x was controlled by the power of pure TaC and Y targets in magnetron sputtering. The structure of the formed (TaC) 1Àx Y x film was that of either a face-center cubic (fcc) at all compositions of x 0:4 or amorphous at x ! 0:5 after annealing at temperatures below 600 C. X-ray photoelectron spectroscopy (XPS) analysis revealed that the TaC and (TaC) 1Àx Y x films all contained about 10% oxygen. The resistivity of the (TaC) 1Àx Y x films was invariant for all compositions of x 0:5, but it increased with increasing annealing temperature up to 600 C for compositions of x ! 0:68. In the asdeposited case, the effective work function, which was estimated from the relationship between V fb and the equivalent oxide thickness of the HfO 2 film, clearly changed from 4.8 to 4.3 eV as x increased. The V fb of HfO 2 and HfSiO x dielectrics could be controlled within 0.5 V after annealing at 500 C by changing the composition of the (TaC) 1Àx Y x film (in terms of x ). Based on the experimental data, it is clear that (TaC) 1Àx Y x composites are candidate materials for n-metal gate electrodes in the gate-last process. #

Nanostructured Cr-Zr-N thin films were grown on Si(100) substrates in a mixture of Ar and N 2 plasma. The nitrogen partial pressure was varied to produce and control the stoichiometric forms obtained. All the Cr-Zr-N films exhibited a nanostructure with an average grain size of less than 10 nm, as determined by X-ray diffractogram analysis, and were formed in the solid-solution. As the contents of nitrogen in the film increased, it lead to changes in the crystal texture and competitive growth. The maximum root mean square roughness was 7.87 nm at a 20% nitrogen partial pressure and the roughness tended to decrease as the grain size decreased. The nano-indentation showed that the films grown at a 20% nitrogen partial pressure and annealed at 700 C had the highest reduced modulus and hardness at 349.2 and 35.1 GPa, respectively. The mechanical properties of films can be improved by a post-annealing heat treatment. With respect to the electrical properties of these films, the sheet resistance, which is related to the defect level, tended to increase as the nitrogen partial pressure increased.

Ti-W-N thin films grown on Si (100) and AISI D2 steel substrates had been deposited by a d.c. magnetron sputtering with pure Ti and W targets in a mixture of Ar and N2 plasma. The nitrogen partial pressure was varied from 0% to 9% of total gas. All Ti-W-N films were formed in solid solution with determination by x-ray diffractrogram analysis. A strong preferred orientation TiN(111) was detected. Their mechanical properties were studied using nanoindentation with Berkovich tip. An increase in hardness was observed with increasing nitrogen partial pressure. The optimum protective coating for plastic deformation was Ti-W-N film grown at 9% nitrogen partial pressure. Chemical bonding of Ti-W-N films was investigated by x-ray photoelectron spectroscopy. Binding energy analysis showed that N was mainly in TiN and W2N. The corrosion behavior was studied in variation of nitrogen partial pressure. Ti-W-N films deposited on steel at low nitrogen partial pressure showed excellent corrosion resistance in NaCl solution.

No abstract

Vulcanized rubber surface was modified by dielectric barrier discharge (DBD) plasma system. The hydrophilic surface can be achieved in the shortly treatment and confirmed by contact angle measurement. The increasing hydrophilic group on rubber surface was monitored by Attenuated total reflectance fourier transform infrared spectrometer called as ATR-FTIR. The surface roughness was investigated to decrease from 202.13 to 82.02 nm after DBD plasma at treatment time 180s.The optimum conditions for making contact angle lower to 22 degree by DBD plasma treatment in this work were; treatment time, 15 s; input voltage on a neon sign transformer, 200 V; electrode gap, 6 mm.