A5007345151- Ga2O3 and related materials
- Semiconductor materials and devices
- Diamond and Carbon-based Materials Research
- GaN-based semiconductor devices and materials
- Metal and Thin Film Mechanics
- ZnO doping and properties
- 2D Materials and Applications
- Graphene research and applications
- Photocathodes and Microchannel Plates
- Advanced Surface Polishing Techniques
- MXene and MAX Phase Materials
- Integrated Circuits and Semiconductor Failure Analysis
- Nanowire Synthesis and Applications
- Electronic and Structural Properties of Oxides
Korea Polytechnic University
2016-2021
A DUV-LED with a graded superlattice electron blocking layer (GSL-EBL) is demonstrated to show improved carrier injection into the multi-quantum well region. The structures of modified EBLs are designed via simulation. simulation results behavior mechanism DUV-LEDs single EBL (S-EBL), (G-EBL), and GSL-EBL. variation in energy band diagram around region indicates that introduction GSL-EBL very effective enhancing injection. Besides, all emitting at 280 nm grown high temperature metal organic...
In this paper, a gradient electron blocking layer (GEBL) is introduced to improve efficiency of deep‐ultraviolet light‐emitting diodes (DUV‐LEDs). Various structures DUV‐LEDs are simulated determine the energy band diagram variation and carrier injection mechanism resulting from insertion GEBL. The simulation results show improved hole transport behavior in AlGaN multi quantum wells (MQWs). Especially, holes with increasing number GEBL steps, which lead enhancement internal (IQE). DUV‐LED...
Herein, the effect of crystal quality AlN buffer layer on AlGaN/GaN/AlN double‐heterostructure high‐electron‐mobility transistor (DH‐HEMT) is investigated. The material GaN channel and AlGaN barriers, such as dislocation density interface roughness, deteriorates, 2D electron gas (2DEG) mobility decreases threading (TDD) increases. It also revealed that thickness Al mole fraction barrier are affected by strain variation depending TDD buffer. compressive responsible for 2DEG change affecting...
Abstract The present study investigated the Mg doping effect in gallium nitride (GaN) buffer layers (BLs) of AlGaN/GaN high-electron-mobility transistor (HEMT) structures grown on semi-insulating 4H-SiC substrates by metal organic chemical vapor deposition. When concentration was increased from 3 × 10 17 to 8 18 cm −3 , crystal quality slightly deteriorated, whereas electrical properties were significantly changed. leakage approximately 50 times 0.77 39.2 nA at −50 V with concentration....
Herein, the growth of lateral‐structure p‐type diamond Schottky barrier diodes (SBDs) on a heteroepitaxial substrate using thin atomic‐layer‐deposited hafnium oxide () interfacial layer is demonstrated. The SBD grown microwave plasma chemical vapor deposition (MPCVD) with 1 kW power at 2.45 GHz. Two kinds samples are substrates under same conditions for identical epi structures. And 10 nm thickness used as an insulator MIS SBD. effects interlayer electrical properties SBDs investigated...
The AlGaN/AlN/GaN/AlN double‐heterostructure high‐electron mobility transistor (DH‐HEMT) on sapphire substrate is introduced, and its direct current (DC) radio frequency (RF) characteristics to the conventional GaN‐based single‐heterostructure HEMT (SH‐HEMT) SiC are compared. devices having two‐finger gate fabricated with width of 200 μm length 500 nm. DC performance DH‐HEMT shows a transconductance 0.233 S mm −1 maximum drain density 0.93 A , comparable that SH‐HEMT. There less‐pronounced...
Boron‐doped diamond layers are grown on freestanding heteroepitaxial substrates by microwave plasma chemical vapor deposition (MPCVD) to verify the high potential of large‐size as an ultimate semiconductor material. Due crystallinity and atomically flat surface morphology substrate, MPCVD‐grown boron‐doped layer exhibit excellent properties crystallinity, measured X‐ray diffraction atomic force microscopy. The temperature‐dependent Hall effect measurements conducted at temperature ranges...
We investigated the growth behavior of GaN grown on AlN along with V/III ratio and pressure variation, found out lateral regime for fully coalesced channel layer AlN-based double-hetero structure high electron mobility transistor (HEMT). When increases decreases, compressive stress in increases, pit formation occurs to release stress. The HEMT was device fabricated an optimized layer. two-dimensional gas mobility, sheet density, resistance were 1480 cm2 V−1 s−1, 1.32 × 1013 cm−2, 319 Ω/sq.,...
In this study, we demonstrated the defect-selective etching and epitaxy technique for defect reduction of a heteroepitaxial chemical vapor deposition (CVD) diamond substrate. First, an 8 nm layer nickel was deposited on surface using e-beam evaporator. Then, conducted through in situ single process microwave plasma (MPCVD). After etching, overgrown by MPCVD. The density measured from atomic force microscope image decreased 3.27×10 to 2.02×10 cm −2 . first-order Raman peak shifted 1340 1336...
Herein, the fabrication of MoS 2 /p‐GaN heterostructures via direct chemical vapor deposition (CVD) and transfer methods are demonstrated. The molybdenum disulfide (MoS ) layers grown on p‐GaN sapphire substrates CVD under same growth conditions. Subsequently, in case substrate, from substrate is transferred onto to produce a vertically stacked heterostructure. Atomic force microscopy (AFM) images indicate that directly GaN exhibits granular structure, whereas triangle‐shaped grains. In...