Dipole ring magnet assisted microwave radial line slot antenna plasma processing method and apparatus

#The invention relates to plasma processing with microwave (MW) plasmas, particularly surface wave plasmas (SWP), for example as produced with a Radial Line Slot Antenna, and more particularly, to a method and apparatus providing relatively low electron energies and plasma uniformity near a treated substrate.

#Typically, during semiconductor processing, a plasma etch process is utilized to remove or etch material along fine lines or within vias or contacts patterned on a semiconductor substrate. The plasma etch process generally involves positioning a semiconductor substrate with an overlying patterned, protective layer, for example a photoresist layer, into a processing chamber and etching exposed areas of the substrate through the pattern.

#Once the substrate is positioned within the chamber, it is etched by introducing an ionizable, dissociative gas mixture into the chamber at a pre-specified flow rate, while adjusting a vacuum pump to achieve a processing pressure. Then, plasma is formed when a portion of the gas species is ionized by collisions with energetic electrons. The gas may be ionized by direct current, radio frequency, microwave energy, or other energy sources known to the art. The energetic electrons dissociate some of the gas species in the gas mixture to create reactant species suitable for the exposed-surface etch chemistry. Once the plasma is formed, exposed surfaces of the substrate are etched by the chemistry at a rate that varies as a function of plasma density, average electron energy, and other factors. The process is adjusted to achieve optimal conditions, including an appropriate concentration of desirable reactant and ion populations to more selectively act upon various desired features (e.g., trenches, vias, contacts, etc.) in the exposed regions of substrate. The exposed regions of the substrate where etching is required are typically formed of materials such as silicon dioxide (SiO2), poly-silicon and silicon nitride, for example.

#FIG. 1 is a cross sectional view of one embodiment of the disclosed processing system.

#FIG. 2 is a top view of the processing chamber and DRM configuration.

#A plasma processing method and apparatus are disclosed in various embodiments. However, one skilled in the relevant art will recognize that the various embodiments may be practiced without one or more of the specific details, or with alternative methods, materials, or components. Well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of various embodiments of the invention.

#Similarly, for purposes of explanation, specific numbers, materials, and configurations are set forth in order to provide a thorough understanding of the invention. Nevertheless, the invention may be practiced with alternative specific details. Furthermore, the various embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.

#References throughout this specification to “one embodiment” or “an embodiment” or “certain embodiments” or variations thereof means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention, but do not denote that they are present in every embodiment. Thus, the appearances of the phrases such as “in one embodiment” or “in an embodiment” or “in certain embodiments” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.