Front end of the line process

Abstract

The type of metal precursors and oxygen sources in atomic layer deposition (ALD) crucially affect the bulk properties of high-k gate dielectric films and the interface properties with a substrate, which determines the performance and reliability of logic devices. In this chapter, we review the effect of the assorted metal precursors, such as HfCl4, (HfN(CH3)2)4, Hf(N(C2H5)(CH3))4, and HfOtBu(NEtMe)3 on the various film properties, focusing on the film growth behavior, impurity level, and interface properties. The influences of oxygen sources type, H2O and O3, are also covered. The combination of ALD high-k film with high-mobility Ge or III-V compound semiconductors results in even more complicated interface reactions as compared to the conventional Si substrate, which is also discussed. Finally, various state-of-the-art devices with ALD high-k film such as Ge and III-Vs-based metal-oxide-semiconductor field effect transistors (MOSFETs) and three-dimensional MOSFETs are introduced, and their reliability characteristics are discussed. © 2014 Springer Science+Business Media New York. All rights are reserved.