A 2-DIMENSIONAL MODEL OF LASER-ABLATION OF FROZEN CL-2 - A POSSIBLE NEUTRAL BEAM SOURCE FOR ETCHING APPLICATIONS

Charge damage considerations are prompting the development of neutral beam sources for etching applications. Anisotropic etching with hypert hermal Cl-2 and SF6 beams has been demonstrated. We describe a two-dim ensional plasma chemistry fluid model of laser ablation of frozen Cl-2 in vacuum as a neutral beam source. In this scheme an externally appl ied electric field would be used to enhance the dissociation rate of C l-2 potentially providing an enhanced Cl content in the beam for a gre ater etch rate. Laser ablation generated neutral beams also may contai n a desirable and controllable ion content which may be used to furthe r enhance the etch rate. Limitations of the concept are discussed. (C) 1996 American Institute of Physics.