AVS 51st International Symposium
    Dielectrics Monday Sessions
       Session DI-MoP

Paper DI-MoP6
Structure Properties and Thermal Stability of Plasma Oxynitrided Hf and Zr Thin Films

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: Yi-Sheng Lai, National Cheng Kung University, Taiwan
Authors: Yi-Sheng Lai, National Cheng Kung University, Taiwan
L.-M. Chen, National Cheng Kung University, Taiwan
C.-H. Lu, National Cheng Kung University, Taiwan
J.S. Chen, National Cheng Kung University, Taiwan
Correspondent: Click to Email
Thermal stability is a critical issue in replacing conventional SiO@sub 2@ gate dielectrics with high-@kappa@ materials. The interlayer (IL) growth as well as the interface reaction is of particularly concern in this respect. Growth of the low-dielectric-constant IL usually increases equivalent oxide thickness (EOT) of the high-@kappa@/IL structure, leading to the applicability in the downscaling of the electronic devices. Accordingly, engineering of the interface becomes a challenging issue in fabricating high-@kappa@ gate dielectrics. In this work, we study the characteristics of plasma oxynitrided Hf and Zr thin films. A 50-Å thick Zr or Hf metal film is first deposited on the Si surface and followed by plasma oxynitridation on these metal films in a mixture of N@sub 2@O+NH@sub 3@ ambient. Incorporation of O and N leads to the formation of ZrO@sub x@N@sub y@ and HfO@sub x@N@sub y@ films. The increased nitrogen content is found to increase the onset of the crystallization temperature in both ZrO@sub x@N@sub y@ and HfO@sub x@N@sub y@ films. Growth of the IL examined from the X-ray photoelectron spectroscopy is also dependent on the incorporated nitrogen content. The thermal stability related to the difference of nitrogen content between ZrO@sub x@N@sub y@ and HfO@sub x@N@sub y@ films is also addressed.