Characterization of the etch rate non-uniformity in a magnetically enhanced reactive ion etcher

Abstract

Study of the impact of the time-delay effect on the critical dimension of a tungsten silicide/polysilicon gate after reactive ion etching Magnetic field optimization in a dielectric magnetically enhanced reactive ion etch reactor to produce an instantaneously uniform plasma A constant concern in semiconductor manufacturing is plasma induced damage. A non-uniform etching plasma can induce a dc current at the wafer surface that can damage the film and therefore the device. The magnetic field in an Applied Materials magnetically enhanced reactive ion etch chamber has been enhanced to provide minimal self-bias non-uniformity. The objective of this article is to characterize the magnetic field through a comparison of experimental etch data and modeling. Both analytical and empirical modeling have been used to gain a better understanding of the particular magnetic field configuration under investigation. At low pressure the etch rate pattern correlated well with the calculated stationary magnetic field gradient. For higher pressure this model failed to predict the etch rate uniformity behavior because of contributions from other effects in the plasma. In order to characterize these effects, experiments were conducted for both stationary and rotating magnetic fields. This was done to aid process optimization with respect to the potential for damage.

Etching of porous SiOCH materials in fluorocarbon-based plasmas

“…Indeed ion bombardment can break Si-O, Si-CH 3 , and C -H bonds and then release H, which can diffuse through the bulk and generate a volatile product such as CH 4 . The film degradation directly scales with the degree of porosity in the material.…”

“…4 For all etch processes, the magnetic field is kept constant at 20 G. The chamber is pumped down by a turbomolecular pump from Alcatel, providing a pumping speed of 1600 l s −1 . The Applied Materials eMAX™ MERIE etcher generates a capacitively coupled plasma.…”

Impact of low-k structure and porosity on etch processes

“…51 For all etch processes, the magnetic field was kept constant at 20 G. More information about the experimental setup is supplied in previous works. This chamber was installed on an experimental cluster located in a class 10 cleanroom.…”

Satistical Analysis of SiO2Contact Hole Etching in a Magnetically Enhanced Reactive Ion Etching Reactor

“…The chamber has four electromagnets controlled by two magnetic drives that allow two magnet pairs (a primary and a secondary pair) to be run at different magnetic field magnitudes [17,18]. The stronger field in the primary pair was referred to as the magnetic field magnitude B.…”

“…Etching of SiO 2 contact holes was conducted in a MERIE chamber for plasma etching of dielectrics manufactured by Applied Materials [17]. The chamber has four electromagnets controlled by two magnetic drives that allow two magnet pairs (a primary and a secondary pair) to be run at different magnetic field magnitudes [17,18].…”