AVS 51st International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS-TuP

Paper PS-TuP2
Design and Development of an Advanced Dielectric Etch Tool using Simulation

Tuesday, November 16, 2004, 4:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: K. Bera, Applied Materials, Inc.
Authors: K. Bera, Applied Materials, Inc.
Y. Ye, Applied Materials, Inc.
D. Hoffman, Applied Materials, Inc.
G.A. Delgadino, Applied Materials, Inc.
J. Carducci, Applied Materials, Inc.
Correspondent: Click to Email
Creating a successful all-in-one (main etch, PR ash, and clean) chamber for dual damascene etch requires thorough understanding of the relationships among plasma density, ion energy, and distribution of charged and neutral species to achieve operational capability over a wide range of plasma density and ion energy at widely different pressures and gas flows. This paper presents several aspects of hardware design and process optimization for a 300mm etcher for 90nm technology and below in which simulation was used to gain insight into these phenomena. Plasma simulations demonstrated that higher frequencies generated denser plasma for a given power than lower frequencies, which focused the selection of source frequency for the reactor. Higher frequencies were shown to improve the dissociation fraction promoting creation of desirable facet-protecting polymers. Simulations further revealed that higher frequencies produced lower-energy, less potentially damaging ion bombardment to the wafer. Simulations guided effective chamber cleaning using source. Confinement ring design was optimized using plasma simulation that allowed us to confine plasma for clean mode operations. Flow simulation calculated chamber conductance guiding the chamber design for wide process window. Simulation showed that Neutral Species Tuning Unit (NSTU) can tune pressure and velocity uniformities, and hence CD-bias and profile uniformities. Separate control of plasma density and energy distribution from distribution of neutral and charged species within the chamber was used to demonstrate independent optimization of the etch rate and CD-bias uniformities for dual damascene trench etch process.