Covering of substrate holes through particle deposition

Abstract

A methodology is proposed to determine the minimum coating thickness for covering substrate holes through particle deposition. The particle deposition process is carried out with a combined, two-dimensional, on-lattice model, in which both deterministic and nondeterministic driving forces are taken into account. The normalized covering thickness (hc/Dw) is investigated subject to variation in the Peclet number (Pe) and the size of the depositing particle, normalized hole size (Dw/L), and degree of postcontact restructuring allowed. It is found that ballistic particle movement gives a slightly better covering structure for smaller holes while diffusive particle movement much more efficiently covers larger holes. The normalized covering thickness increases with increasing normalized hole size and with decreasing normalized depositing particle size. Postcontact restructuring first improves the covering capability of the depositing particle, but then impairs it if further restructuring is allowed. It is further found that the normalized covering thickness scales with the normalized hole size as hc/Dw∼(Dw/L)E with E=0.67, 0.56, and 0.36 for Pe of infinity, 0.5, and 0.1, respectively.