E. Babich, J. Paraszczak, et al.
Microelectronic Engineering
The distribution and transport of particles in materials processing plasmas has been studied with a rastered laser light scattering technique. Contrary to expectation, the distribution of particles in a plasma processing tool is rarely random. Instead, structured clouds of particles form at the plasma/sheath boundary. The effect is attributed to trapping of the particles by weak electric field nonuniformities and the characteristic negative charge of isolated particles in a plasma. Field nonuniformities appear to be influenced by the topography and material design of the tool. For example, the presence of a Si wafer often induces significant particle trapping. Examples of particle trapping in a laboratory system are given, and similar phenomena are also verified in a manufacturing sputter deposition tool operating in a class 100 cleanroom. The implications of particle trapping in plasma processing are discussed. © 1991 American Vacuum Society
E. Babich, J. Paraszczak, et al.
Microelectronic Engineering
Gregory Czap, Kyungju Noh, et al.
APS Global Physics Summit 2025
Ming L. Yu
Physical Review B
Dipanjan Gope, Albert E. Ruehli, et al.
IEEE T-MTT