AVS 46th International Symposium
    Plasma Science and Technology Division Thursday Sessions
       Session PS1-ThA

Paper PS1-ThA4
High Density Plasma Oxide Etching of SAC (Self-Aligned Contact) and 0.25 micron HARC (High Aspect Ratio Contact) Structures: Process and Repeatability Results

Thursday, October 28, 1999, 3:00 pm, Room 612

Session: High Fidelity Pattern Transfer
Presenter: L. Marquez, Lam Research
Authors: L. Marquez, Lam Research
B. Bosch, Lam Research
O. Turmel, Lam Research
S. Darcy, Lam Research
J.M. Cook, Lam Research
Correspondent: Click to Email
A major challenge of SiO@sub2@ etching for sub-0.25 micron design rules is the stability of the process both long and short term. The very small, often deep, features together with the requirement for high selectivity guarantee that a very high degree of control of both the hardware and the process is essential. Stable SAC and HARC (> 10:1 aspect ratio) processes have been developed in an inductively coupled, high-density plasma dielectric etch tool. The repeatability of the processes was found to be dependent on the stability of the reactor's surface temperature, the material properties of the reactor's walls and the overall cleanliness of the chamber. The trends (etch rate, selectivity, uniformity, etc.) of the processes have been investigated in terms of power, pressure, flow, chemistry and wall temperatures. It is necessary to understand these trends in order to optimize the various process parameters such as selectivity and uniformity. The impact of surface temperature and material properties on the process results will also be discussed. Several marathons with both the SAC and HARC processes have demonstrated the manufacturability of both the processes and the high density plasma dielectric etch tool. The results of these marathons will be presented.