Physical and electrical characteristics of metal-organic decomposed CeO2 gate spin-coated on 4H-SiC

Oxygen vacancy formation and annihilation in lanthanum cerium oxide as a metal reactive oxide on 4H-silicon carbide

“…Keeping pace with the prevalent application of cerium oxide (CeO 2 ), straddling areas from catalysis 1,2 to solid oxide fuel cells, 3 gas sensors, 4 and more recently as a passivation 5,6 and catalytic layer, 7,8 or the so-called metal reactive oxide on semiconductor substrates, the inherent properties of CeO 2 associated with its reversible change from the +4 to +3 oxidation state have been unveiled. Oxygen vacancies have been found as the indispensable key defects in CeO 2 , coupling with changes between the two oxidation states (Ce 4+ to Ce 3+ ) in order to achieve the desired redox-ability in the oxide.…”

Structural and Chemical Studies of Metal–Organic Decomposed LaxCeyOz Thin Film as a Catalytic Oxide on 4H-SiC as a Function of Postdeposition Annealing Time

“…Results indicate that transformation of the film composition from La x Ce y O z -dominant to La 9.33 Si 6 O 26 -dominant happens as PDA time approaches 120 min. This La 9.33 Si 6 O 26 -dominant film is preferentially oriented in the (012) plane, as conveniently depicted by coefficient of texture ( T hkl ) , that shows T hkl greater than 1.…”

“…Of these high k gate oxides, cerium oxide (CeO 2 ) has been of particular interest. The CeO 2 has been intensively studied as the gate oxide on various semiconductor substrates, which include Si, , Ge, , 4H-SiC, − and GaN − for metal-oxide-semiconductor (MOS)-based structures. Apart from functioning as a passivation layer in the MOS-based structures, the CeO 2 is also well-known for its catalytic property. , The presence of intrinsic oxygen vacancies in the CeO 2 lattice as well as the redox-ability of the CeO 2 to switch between Ce 4+ and Ce 3+ states has motivated exploration of the CeO 2 . ,, Literature revealed that redox-ability of the CeO 2 is deactivated at high temperature annealing (beyond 800 °C) because active O ions in the CeO 2 lattice are deactivated by inactive O ions .…”

Growth and Characterization of Ternary HfxTayOz Films via Nitrogen-Infused Wet Oxidation

“…One of the main components of sustaining low leakage current in Si-based MOS devices was attributed to the possibility of growing high-quality silicon dioxide (SiO 2 ) as the passivation layer. Unfortunately, the continuous downscaling of low-dielectric-constant ( k ) SiO 2 throughout the years has pushed SiO 2 thickness to a limit, wherein a considerably high leakage current governed by direct tunneling mechanism was ensured when the thickness of SiO 2 was reduced down to the region of a few nanometers. − To mitigate the influence governed by direct tunneling mechanism, there is a need of replacing the SiO 2 with novel materials composed of high k values, such as Al 2 O 3 , Y 2 O 3 , ,, ZrO 2 , La 2 O 3 , HfO 2 , Ta 2 O 5 , , , and CeO 2 , , as the passivation layer for Si-based MOS devices. Of these high- k materials, Ta 2 O 5 has gained increasing attention, owing to the possibility of being employed as a storage dielectric film and a passivation layer for dynamic random-access memories (DRAM) and Si-based MOS devices, respectively.…”