Ammonia pretreatment for high-κ dielectric growth on silicon

Abstract

Enhanced initial growth of atomic-layer-deposited metal oxides on hydrogen-terminated silicon Appl. Phys. Lett. 83, 740 (2003); 10.1063/1.1595719 Ultrathin nitrided-nanolaminate ( Al 2 O 3 / ZrO 2 / Al 2 O 3 ) for metal-oxide-semiconductor gate dielectric applications J.

X-ray reflectometry and spectroscopic ellipsometry characterization of Al2O3 atomic layer deposition on HF-last and NH3 plasma pretreatment Si substrates

“…To minimize the interfacial layer and improve the electrical properties, treatment of the Si surface with ammonia (NH 3 ) has been adopted before Al 2 O 3 deposition. [15][16][17] Furthermore, it is highly desirable to know the effect of NH 3 pretreatment on Al 2 O 3 growth characteristics, including, for example, the interfacial layer and the growth rate.…”

“…The interlayer thicknesses that are almost independent of the number of growth cycles on nitrided substrates indicate that the diffusion of oxygen to silicon is hindered by the initial SiO x N y layer. The absolute amount of nitrogen in all nitrided samples is constant, also indicating nearly no additional interface formation during the Al 2 O 3 film growth process 15,16. …”

Electron paramagnetic resonance evaluation of defects at the (100)Si/Al2O3interface

“…11 and zirconium oxide on silicon, which show that nitridation of the silicon substrate produces a better quality interface [10,11].…”

“…We quantify the unpassivated defect density, examine the origin of the Si-db defect, and report on the effects of a pre-deposition nitridation step -which has been shown in a number of dielectrics to improve interface quality [10,11] above that of ALD grown films on HF-treated substrates, which may result in uneven nucleation and discontinuous films [10,12]. We also show the effects of postdeposition annealing in forming gas.…”

SiON as a barrier layer for depositing an Al2O3 thin film on Si for gate applications

“…However, attempts to use MOCVD to deposit high-k dielectrics directly on H-terminated silicon have resulted in the formation of an unwanted aluminum silicide interfacial layer which can degrade device performance and reliability. [7] Currently, silicon nitride has often been proposed as a barrier layer between high-k materials and Si to avoid silicate formation. [8,9] However, an SiN layer on the Si channel results in significant degradation of channel mobility and drive current due to the excess charge of pentavalent nitrogen atoms and a high defect density at the interface.…”