A low temperature fabrication of HfO(2) films with supercritical CO(2) fluid treatment

作者：Tsai, Chih Tsung^*; Chang, Ting Chang; Kin, Kon Tsu; Liu, Po Tsun; Yang, Po Yu; Weng, Chi Feng; Huang, Fon Shan

来源：Journal of Applied Physics, 2008, 103(7): 074108.

DOI：10.1063/1.2844496

To improve the dielectric properties of sputter-deposited hafnium oxide (HfO(2)) films, the supercritical CO(2) (SCCO(2)) fluid technology is introduced as a low temperature treatment. The ultrathin HfO(2) films were deposited on p-type (100) silicon wafer by dc sputtering at room temperature and subsequently treated with SCCO(2) fluids at 150 degrees C to diminish the traps in the HfO(2) films. After SCCO(2) treatment, the interfacial parasitic oxide between the Si substrate and HfO(2) layer is only about 5 A, and the oxygen content of the HfO(2) films apparently increased. From current-voltage (I-V) and capacitance-voltage (C-V) measurements, the leakage current density of the SCCO(2)-treated HfO(2) films is repressed from 10(-2) to 10(-7) A/cm(2) at electric field=3 MV/cm due to the reduction of traps in the HfO(2) films. The equivalent oxide thickness also obviously decreased. Besides, the efficiency of terminating traps is relative to the pressure of the SCCO(2) fluids.

• 出版日期2008-4-1
• 单位中山大学; 清华大学; 中国科学院电工研究所