Depletion-mode GaAs-based MOSFET with Ga2O3(Gd2O3) as a gate dielectric

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

“…The performance is comparable to that of a conventional D-mode device configuration reported by Wang et al [20] in a GaAs MOSFET with GGO gate dielectric 38 nm thick, Tsai et al [9] in an In 0.2 Ga 0.8 As MOSFET with GGO 54 nm thick, and Ye et al [4] in an In 0.2 Ga 0.8 As MOSFET with ALD-Al 2 O 3 16 nm thick. Our data, however, compare very favorably with those of ring-gate D-mode MOSFETs with PVD HfO 2 gate dielectrics and Si and Ge as interfacial layers [21,22].…”

“…These oxides have been employed to fabricate depletion-mode (D-mode) [9,10] and inversion-channel InGaAs MOSFET [11][12][13][14][15]. In comparison, the D it 's measured in the GaAs MOS capacitors (MOSCAPs) using MBE-GGO are in the range of $10 11 cm À2 eV À1 , one order of magnitude lower than those of capacitors using ALD oxides.…”

Oxide scalability in Al2O3∕Ga2O3(Gd2O3)∕In0.20Ga0.80As∕GaAs heterostructures

“…10,11 MOS diodes of Au/ Al 2 O 3 ͑3 nm͒ / GGO/ In 0.20 Ga 0.80 As/ GaAs for GGO thicknesses of 33, 20, and 10 nm with the same annealing as in the diode with GGO 8.5 nm thick have been studied and the results are summarized in Table I. The relationships between GGO thickness and relevant electrical properties are now revealed: ⌬V fb becomes larger with increase in t ox , whereas values maintain at [14][15]. J values at ͉V G − V fb ͉ = 1 V are very low of 10 −9 A / cm 2 .…”

“…10,11 The employment of GGO as a gate dielectric on GaAs and InGaAs, in conjunction with ion implantation and rapid thermal annealing ͑RTA͒ for activating implanted ions, has led to successful demonstration of inversion-channel and depletion-mode MOSFETs. [12][13][14] However, rare earth containing oxides such as GGO tend to absorb moisture during air exposure, 15 resulting in oxide degradation and poor device performance. Annealing under ultrahigh vacuum ͑UHV͒ or flowing N 2 of air-exposed oxides ͑with thickness Ͼ20 nm͒ in a proper heat treatment has removed moisture from GGO, thus restoring low D it and low leakage currents, and maintaining smooth oxidesemiconductor interfaces with RTA to high temperatures of ϳ800°C.…”

Inversion-channel enhancement-mode GaAs MOSFETs with regrown source and drain contacts

“…The device process flow started with molecular beam epitaxial (MBE) growth of beryllium-doped p-type GaAs grown on SI-GaAs substrate followed by an in-situ deposition of 20-nm-thick GaGdO as the gate dielectric in an interconnected ultra-high vacuum oxide deposition chamber [8]. After removed from the growth chamber, titanium is deposited and patterned on the sample as a sacrificial gate, which will help to lift-off the overgrown III-V material after the regrowth process.…”