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

The first industrial application of ALD in microelectronics dates back to 2007, with the introduction of HfO₂ gate dielectrics in Intel’s 45-nm transistors. Although this technique had been available since 1998, microelectronics manufacturers were skeptical about its use in production. When the decision to use HfO₂ as the gate dielectric was made in the early 2000s, manufacturers initially attempted to produce it via physical vapor deposition (PVD), due to its cost-effectiveness in manufacturing, shorter deposition time, and lower maintenance costs. However, all PVD trials resulted in the formation of an HfO₂ film of inferior electrical quality—either with gaps or with physical impact from species at the underlying interface.

This typical example shows that ALD is used in production only when the manufacturer has no other choice, which is the case, for example,...