Study of Magnetron Sputter Deposition of Metal Gate Electrodes

Abstract

AbstractA systematic study of magnetron sputter deposition of metal gate is presented. On-wafer probes were used to measure ion current and floating voltage. Charge monitoring wafers was used to evaluate charging damage. C-V measurements showed that the interface trap density of metal gated MOS capacitors was reduced with thicker dielectric layer thickness and with the insertion of ALD deposited buffer layer. Lower pressure, higher sputtering power, and pulsed DC sputtering were found to cause larger plasma damage to the ultra-thin dielectric layer, most likely due to increased energetic particle bombardment as a result of higher plasma density and higher ion and neutral energies.