ALD in Microelectronics devices - Evolution and Use in Advanced Micro-Devices

Atomic Layer Deposition (ALD) is a material deposition technique used in the fields of electronics and microelectronics due to its ability to deposit thin films with atomic-level precision. This sequential deposition method allows for precise control of the thickness and composition of thin films, which is critical for the fabrication of advanced electronic devices.

The ALD technique is particularly valued for its conformality—that is, its ability to uniformly coat substrates with complex geometries, including three-dimensional structures. This characteristic is essential in microelectronics, where devices are becoming increasingly complex and miniaturized. Thus, the main advantage of ALD in this field is its ability to fabricate very thin films with excellent control over their thicknesses, chemical compositions, and microstructures, whether on flat surfaces or complex topographies.

This article is an expansion of the version published in 2015. That version remains relevant. Readers are encouraged to consult it to learn about ALD implementation techniques in microelectronics. Furthermore, it is strongly recommended to visit[RE 253] to familiarize yourself with the principles of ALD.

ALD is widely used in advanced logic devices, particularly in transistors and memory devices. We present these two areas, illustrating the use of ALD in the fabrication of gates for advanced FDSOI transistors and nanowires, as well as the latest advances in HfO₂-based ferroelectric memories.