1 nm equivalent oxide thickness in Ga2O3(Gd2O3)∕In0.2Ga0.8As metal-oxide-semiconductor capacitors

Abstract

Articles you may be interested inHigh quality HfO2/p-GaSb(001) metal-oxide-semiconductor capacitors with 0.8nm equivalent oxide thickness Appl. Phys. Lett. 105, 222103 (2014); 10.1063/1.4903068 Modeling and analysis of the admittance characteristics of n+ metal-oxide-semiconductor capacitors with oxide and interface states -Gd0.25Ga0.15O0.6/Ga2O3 on In0.53Ga0.47AsLow interfacial trap density and sub-nm equivalent oxide thickness in In0.53Ga0.47As (001) metal-oxidesemiconductor devices using molecular beam deposited HfO2/Al2O3 as gate dielectrics Appl. Phys. Lett. 99, 042908 (2011); 10.1063/1.3617436Engineering of threshold voltages in molecular beam epitaxy-grown Al 2 O 3 ∕ Ga 2 O 3 ( Gd 2 O 3 ) ∕ In 0.2 Ga 0.8 As J.An equivalent oxide thickness about 1 nm for Ga 2 O 3 ͑Gd 2 O 3 ͒ ͑GGO͒ on In 0.2 Ga 0.8 As has been achieved by employing a thin in situ deposited 3 nm thick Al 2 O 3 protection layer. The dual gate oxide stacks of the Al 2 O 3 / GGO ͑33, 20, 10, 8.5, and 4.5 nm͒/In 0.2 Ga 0.8 As/ GaAs metal-oxide-semiconductor ͑MOS͒ capacitors remain amorphous after rapid thermal annealing up to 800-850°C, accompanied with atomically sharp smooth oxide/semiconductor interfaces. Well behaved capacitance-voltage ͑C-V͒ curves of the MOS diodes have shown sharp transition from depletion to accumulation with small flatband voltage ͑1.1 V for Au metal gate and 0.1 V for Al͒, and weak frequency dispersion ͑1.5%-5.4%͒ between 10 and 500 kHz at accumulation capacitance. Low leakage current densities ͓3.1ϫ 10 −5 and 2.5ϫ 10 −9 A / cm 2 at V = V fb + 1 V for Al 2 O 3 ͑3 nm͒ / GGO͑4.5 and 8.5 nm͔͒, a high dielectric constant around 14-16 of GGO for all tested thicknesses, and a low interfacial density of states ͑D it ͒ in the low 10 11 cm −2 eV −1 have also been accomplished.

Nanometer‐Thick Single‐Crystal Hexagonal Gd2O3 on GaN for Advanced Complementary Metal‐Oxide‐Semiconductor Technology

“…However, like HfO 2 -based high-k dielectrics, amorphous GGO may recrystallize into a polycrystalline material during RTA at 1100 8C, thus, increasing the electrical leakage. Furthermore, the dielectric constant of GGO is about 14-16, [18] probably not large enough to reduce the CET below 1 nm.…”

“…Amorphous GGO, shown to effectively passivate InGaAs [18] and Ge [19] and with a CET approaching 1 nm on InGaAs, has exhibited remarkable thermal stability with InGaAs; GGO/ InGaAs withstands high-temperature rapid thermal annealing (RTA) to 850 8C with structural intactness and maintains excellent electrical properties, as revealed by capacitance-voltage (C-V) and current-density-electrical-field (J-E) measurements. However, like HfO 2 -based high-k dielectrics, amorphous GGO may recrystallize into a polycrystalline material during RTA at 1100 8C, thus, increasing the electrical leakage.…”

Research advances on III–V MOSFET electronics beyond Si CMOS

“…[2][3][4][23][24][25]27,28], GGO was found to give the lowest interfacial densities of states [3]. Therefore, the essential issue of the thickness scalability of the GGO oxide on InGaAs was addressed, and a CET approaching 1 nm was demonstrated [29,30]. The GGO/ In 0.2 Ga 0.8 As (InGaAs) gate stacks were fabricated with the oxide thickness systematically reduced from 33 to 4.5 nm.…”

Depletion-mode In0.2Ga0.8As/GaAs MOSFET with molecular beam epitaxy grown Al2O3/Ga2O3(Gd2O3) as gate dielectrics

“…A Si-doped In 0.2 Ga 0.8 As (7 nm)/GaAs (90 nm) channel with a doping concentration of 4 Â 10 17 cm À3 was grown on semi-insulating GaAs (1 0 0) substrate. The wafers with freshly grown InGaAs/GaAs epi-layers were then moved to the oxide chambers for Al 2 O 3 /GGO growth [18,19]. A GGO dielectric 6 nm thick was MBE-deposited on InGaAs/GaAs channels at a substrate temperature 520 1C.…”

“…GGO, containing rare earth Gd, tends to absorb moisture during air exposure, thus degrading the electrical properties [17]. In-situ deposited Al 2 O 3 was found to be very effective in protecting GGO from absorbing moisture to give an excellent thermodynamic stability [18,19].…”