AVS 52nd International Symposium
    Thin Films Monday Sessions
       Session TF-MoP

Paper TF-MoP2
Effects of Annealing Gas on Characteristics of HfO@sub 2@ Deposited by ALD for MIM Capacitors

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Aspects of Thin Films Poster Session
Presenter: S.-W. Jeong, Sungkyunkwan University, Korea
Authors: S.-W. Jeong, Sungkyunkwan University, Korea
H.J. Lee, Sungkyunkwan University, Korea
K.-S. Kim, Sungkyunkwan University, Korea
M.-T. Yoo, Sungkyunkwan University, Korea
Y.-H. Roh, Sungkyunkwan University, Korea
T. Noguchi, Samsung Advanced Institute of Technology, Korea
J. Jung, Samsung Advanced Institute of Technology, Korea
W. Xianyu, Samsung Advanced Institute of Technology, Korea
Correspondent: Click to Email
Research on the insulating films in metal-insulator-metal (MIM) capacitors has focused on ways to increase the dielectric constant of insulator to improve the packing density of integrated RF capacitors. High-k oxide (e.g., Ta@sub 2@O@sub 5@) has been suggested as an alternative material to replace SiO@sub 2@ and Si@sub 3@N@sub 4@. However, reliability problem caused by leakage current may limit the application of Ta@sub 2@O@sub 5@. Properties of HfO@sub 2@ grown on the Si substrate shows a dielectric constant which is comparable to that of Ta@sub 2@O@sub 5@. Further, the characteristics of HfO@sub 2@ more stable than those obtained from Ta@sub 2@O@sub 5@, suggesting that we may use HfO@sub 2@ film as insulator in MIM capacitor. In this work, we report the physical and electrical properties of ALD-deposited HfO@sub 2@ film (11-12 nm) annealed at various gases (N@sub 2@, O@sub 2@, N@sub 2@O). HfO@sub 2@ films were annealed at 400, 600, 800 °C using a rapid thermal processor for 1 min. Top and bottom metal electrodes were Pt and Pd, respectively. The electrical characterization indicates that HfO@sub 2@ MIM capacitors fabricated at 800 °C under O@sub 2@ ambient show the most desirable electrical properties, such as a high capacitance density of ~16.9 fF/µm@super 2@, a low leakage current of 2.7*10@super â?"4@ A/cm@super 2@ at -5 V, low-voltage coefficients of capacitance, and good-frequency dispersion properties. In addition, better properties were obtained from the samples annealed using N@sub 2@O than those of samples treated using N@sub 2@. These results indicate that oxygen content has certain role(s) on the electrical properties of ALD-deposited HfO@sub 2@ film. These results, as well as further investigation of physical properties of the samples using XPS, will be presented at the conference.