Impact of ALCVD and PVD Titanium Nitride Deposition on Metal Gate Capacitors

Abstract

In this paper it will be shown that the deposition method is an important parameter for the electrical properties of the metal gate. Indeed, ALCVD(Atomic Layer Chemical Vapor Deposition) TiN metal has a 5.3eV workfunction, suitable for PMOS devices. The PVD sputtered (Physical Vapor Deposition) TiN has a lower workfunction around 4.8eV and is mid-gap like. The PVD TiN capacitors have a higher effective oxide charge than the ALCVD capacitors as extracted from capacitance measurements and from workfunction calculations. PVD TiN also exhibits process-induced damage as seen from leakage measurements.