ALD in Microelectronic. Applications, Equipments and Productivity

ALD is a relatively latecomer to microelectronics, having been introduced in integrated circuit manufacturing units in the early 2000s. The main advantage of ALD is its ability to manufacture very thin films with excellent control over thickness, chemical composition and microstructure, whether on flat surfaces or complex topographies. What's more, thanks to its surface saturation principle, ALD is not sensitive to local consumption, as is the case with the CVD technique, which can lead to differences in deposited thickness depending on pattern density. Finally, the deposition temperature is generally lower than with CVD, often well below 400°C, making it compatible with fragile underlying stacks.

This article presents the various applications of ALD in the microelectronics industry, in chronological order of introduction into production units. The various types of equipment used are then described, with a presentation of the different solutions for improving process profitability, a crucial parameter in this mature industry today.