Techniques herein provide an etch-based planarization technique. An initial film is deposited on a substrate. Deposition of this initial film results in a non-planar film because of differences in area density of underlying structures (for example, open areas compared to closely spaced trenches). Etch processes are executed that use a reverse lag RIE process to planarize the initial film, and then another coat of the film material can be deposited, resulting in a planar surface. Such techniques can planarized substrates without using chemical mechanical polishing (CMP).