Investigation of Thermal Stability of TiN Film Formed by Atomic Layer Deposition Using Tetrakis(dimethylamino)titanium Precursor for Metal-Gate Metal--Oxide--Semiconductor Field-Effect Transistor

In this paper, we describe the superiority of the titanium nitride (TiN) film formed by atomic layer deposition (ALD) using a tetrakis(dimethylamino)titanium (TDMAT) precursor for metal-gate electrodes of planar metal--oxide--semiconductor field-effect transistors (MOSFETs). It was demonstrated that the resistivity of the ALD TiN was significantly reduced by NH3post deposition annealing (PDA). The electrical characteristics of the ALD-TiN-gate MOS capacitors and planar MOSFETs were evaluated and compared with those of the physical-vapor-deposited (PVD) TiN. The performance of the ALD-TiN-gate cases was confirmed to be superior to that of the PVD-TiN-gate cases, which was explained by the lower interface trap density ($D_{\text{it}}$) of the ALD TiN/SiO2gate stack.