Electrical properties of RuO2 gate electrodes for dual metal gate Si-CMOS

The rutile stoichiometric phase of RuO2, deposited via reactive sputtering, was evaluated as a gate electrode for Si-PMOS devices. Thermal and chemica l stability of the electrodes was studied at annealing temperatures of 400 degreesC and 600 degreesC in N-2. X-ray diffraction patterns were measured to study grain structure and interface reactions, Very low resistivity valu es were observed and were found to be a strong function of temperature. Ele ctrical properties were evaluated on MOS capacitors, which indicated that t he workfunction of RuO2 was compatible with PMOS devices, Excellent stabili ty of oxide thickness, flatband voltage and gate current as a function of t emperature was also found. Breakdown fields were also measured for the samp les before and after annealing.