Levitrack ALD

The Levitrack™ ALD system is based on the novel concept of precursor separation in space, instead of by time, in combination with the unique floating wafer and conductive heating technology used in the Levitor RTP products.

Substrates are floating in a linear gas track, and are heated to the required process temperature (below 300°C) within a matter of seconds. At process temperature, the substrates float through a series of ALD deposition cells. Each cell consists of 2 precursors, which are separated in space by a Nitrogen purge (acting as inert gas curtains).

A sequence of precursor 1, Nitrogen purge, precursor 2, and again, Nitrogen purge will result in the deposition of 1 monolayer. The number of active ALD deposition cells depends on the required layer thickness.

The combination of a relatively large purge gas flow, and a narrow gap between the substrate and the gas divider block ensures a very effective separation of the precursors. Mixing of precursors will result in CVD growth of particles.

The unique design of ALD deposition cells technology even allows for single side ALD growth, as one side of the gas track can run with only Nitrogen. Because each ALD deposition cell is optimized for a fast linear motion of the substrates, high throughput is guaranteed.

Product features

• High throughput, due to precursor separation in space.
• No deposition of films on the wall of the track.
• No deposition on the back side of the wafer.
• No vacuum pumps; (the entire track operates at 1 atmosphere).
• Low cost construction materials; with a deposition temperature < 300°C, the entire track can be constructed from aluminum.
• Because of the narrow gap, heating of the wafer is fast.