Effect of gallium incorporation on electrical and material characteristics of TiO2 films for high-permittivity dielectric application
- Resource Type
- Conference
- Authors
- Zhang, Jie; Zhao, Haochen; Zhama, Tuofu; Zeng, Yuping
- Source
- 2022 Compound Semiconductor Week (CSW) Compound Semiconductor Week (CSW), 2022. :1-2 Jun, 2022
- Subject
- Engineered Materials, Dielectrics and Plasmas
Photonics and Electrooptics
Power, Energy and Industry Applications
Gallium
Annealing
Photonic band gap
Films
Crystallization
Silicon
Dielectrics
Ga addition
TiO 2
high-permittivity dielectric
back-end-of line (BEOL)
- Language
In this work, effects of gallium incorporation on electrical and material characterization of TiO 2 films were investigated. These 15 nm Ga-doped TiO 2 films were grown by supercycle atomic layer deposition (ALD) and then annealed at 500 ºC in O 2 ambient. The levels of Ga incorporation to TiO 2 films were controlled by the ratio of Ga to Ti cycles during ALD growth. Material characterizations show that the Ga incorporation destabilizes the crystallization of TiO 2 films, resulting in amorphous films even after 500 ºC O 2 annealing. The bandgap of these Ga-doped TiO 2 films were found to monotonically increase with the increased Ga content. Metal-oxide semiconductor capacitors (MOSCAPs) based on p-type Si substrate were fabricated to evaluate the electrical properties of the Ga-doped TiO 2 films. Both leakage currents and capacitances were reduced as the Ga content increases. These well-behaved dielectrics under 500 ºC process suggest their great promises for back-end-of-line (BEOL) device applications.