Surface dependent effects at the plasma-surface interface

Summary form only given. The complicated interactions at the plasma-surface interface in microelectronics processing discharges impact a wide range of device parameters. In a typical etching application, a number of different materials ranging from the common silicon, and silicon oxide to more exotic nitrides and low-k materials can be located in very close proximity to each other. The interaction of these different materials through changes in the plasma chemistry, non-equilibrium surface layers and local electric field is of fundamental interest since the local chemistry and plasma properties determine the characteristics of the resulting etch profile. Laser based techniques offer an almost ideal probe for these surfaces due to the hostile nature of the plasma, difficulties with probe techniques, and the inherent species selectivity available using optical techniques. This talk will review our LIF measurements of surface-dependent radical-species densities obtained in microelectronics processing discharges, laser photodetachment identification of negative ion species, and recent spatially resolved electric-field measurements above different electrode materials.