SALD vs ALD
Spatial Atomic Layer Deposition (SALD)

The ALD technique was patented in 1977 by T. Suntola . In this first patent, both temporal and spatial approaches had already been proposed. In the first case, precursors are injected in consecutive injections separated by purging steps (and therefore separated in time). In the second, the precursors are supplied continuously at different locations, and it is the substrate that moves from one location to another (so the precursors are deposited spatially separated, see figure