AVS 46th International Symposium
    Plasma Science and Technology Division Friday Sessions
       Session PS-FrM

Paper PS-FrM7
High Anisotropy Etching of 0.18 Micron Platinum Electrodes

Friday, October 29, 1999, 10:20 am, Room 609

Session: Emerging Plasma Applications
Presenter: S.D. Athavale, IBM, Microelectronics Division
Authors: S.D. Athavale, IBM, Microelectronics Division
D.E. Kotecki, IBM, Microelectronics Division
H. Shen, Siemens
J. Hwang, Applied Materials, Inc.
C. Ying, Applied Materials, Inc.
D.J. Lee, Applied Materials, Inc.
S. Mak, Applied Materials, Inc.
Correspondent: Click to Email
Platinum is one of the most promising electrode materials for future high density DRAM capacitors based on high dielectric constant materials such as BST. Achieving veil-free, vertical sidewall profiles, when dry etching platinum, has remained an elusive goal due to the low volatility of etch-products under traditional plasma etching conditions. We have studied etching of platinum using a high-density plasma reactor equipped with a high temperature (>200°C) cathode. Statistical design of experiments (DOE) methodology was used. It has been found that the result of etching Pt is strongly influenced by the wafer temperature. For example, increasing the wafer temperature leads to a dramatic increase in the Pt etch rate and a change in resulting Pt profile. Nearly vertical sidewall profiles (89°) and veil-free Pt etching results are achieved on 0.18µm electrode. The key wafer-level issues and integration challenges associated with the etching of Pt electrodes under high temperature conditions are also discussed.