Trap state characterization of Al₂O₃/AlInGaN/GaN metal-insulator-semiconductor heterostructures

Abstract

Frequency-dependent conductance measurements were carried out to investigate the trap states in Al 2 O 3 /AlInGaN/GaN metal-insulator-semiconductor (MIS) heterostructures. From the electrical measurements, an improvement in trap state characteristics was observed for the device fabricated with lower In composition in quaternary nitride layers. In the presence of higher In composition, segregation of In atoms was observed in AlInGaN layers. Because of this Insegregation, surface quality of the quaternary-N deteriorated that led to the formation of trap states at and near the oxide/semiconductor interface. Therefore, in the presence of lower In composition, an improvement in trap characteristics was observed for the AlInGaN/GaN-based MIS devices.

Simulation of GaN micro-structured neutron detectors for improving electrical properties

“…[29] And its value of 2 × 10 12 cm −2 is employed in this work. [30,31] Conversely, the electron accumulation region is formed near the trench surface due to the positive Q f at the SiO 2 /GaN interface, which is the main factor of increasing the surface leakage along the sidewalls and reducing the V r as shown in Fig. 7(b).…”

Surface-oxide-controlled InGaAs/InAlAs inverted-type metal-oxide-semiconductor high electron mobility transistors for sub-THz high-power amplifiers

“…We have previously reported that the improvement in the g m profile (the wider range of constant g m ) on InP-based HEMTs with a steam-annealed ultrathin-Al 2 O 3 gate dielectric (2 nm thick), due to a reduction in gate leakage current and an increase in forward breakdown voltage. 19) However, when using oxidant sources for ALD-Al 2 O 3 , the narrow band gap (∼3.4 eV) deficient indium oxide (InO x ) is generated in the surface-oxide of the In-based epitaxial layer, [20][21][22][23] thereby increasing the gate leakage current. 24) Thus, we developed inverted MOS-HEMTs with a surface-oxide-control (SOC) process that decreased the amount of InO x at the Al 2 O 3 /semiconductor interface.…”

Surface‐Oxide‐Controlled InAlGaN/GaN High‐Electron‐Mobility Transistors Using Al2O3‐Based Insulated‐Gate Structures with H2O Vapor Pretreatment

“…[29] However, owing to its electron traps such as oxygen vacancies, deficient In 2 O 3 (InO x ) induces the current collapse in GaN HEMTs that use In-based barrier layers. [30][31][32][33] We previously proposed H 2 O vapor oxidation to decrease the amount of InO x in the surface-oxide by focusing on the thermal stability of the intermediate hydroxide and showed a decreased gate leakage current and current collapse in InAlN/GaN HEMTs using H 2 O vapor. [30,31] Alternatively, when using H 2 O vapor as an oxidant source for ALD-Al 2 O 3 (H 2 O vapor-Al 2 O 3 ), the density of the dielectric is lower than that obtained when O 2 plasma (O 2 plasma-Al 2 O 3 ) [34] DOI: 10.1002/pssa.202100638 Herein, Al 2 O 3 /InAlGaN/GaN metal-insulator-semiconductor high-electronmobility transistors (MIS-HEMTs) using H 2 O vapor pretreatment to decrease the amount of deficient indium oxide (InO x ) is successfully developed.…”