Quasiclassical calculation of the fermi level and of the forbidden energy band narrowing in crystal semiconductors with heavy doping

ABSTRACTThe magnetic properties of GaMnN, grown by metalorganic chemical vapor deposition, depend on the addition of dopants; where undoped materials are ferromagnetic, and n -type (Si-doped) and p -type (Mg-doped) films are either ferromagnetic or paramagnetic depending on dopant concentration. The ferromagnetism of this material system seems correlated to Fermi level position, and is observed only when the Fermi level is within or close to the Mn energy band. This allows ferromagnetism-mediating carriers to be present in the Mn energy band. The current results exclude precipitates or clusters as the origin of room temperature ferromagnetism in GaMnN.

Download Full-text

Transparent Conducting Oxides for Photovoltaics: Manipulation of Fermi Level, Work Function and Energy Band Alignment

Materials ◽

10.3390/ma3114892 ◽

2010 ◽

Vol 3 (11) ◽

pp. 4892-4914 ◽

Cited By ~ 252

Author(s):

Andreas Klein ◽

Christoph Körber ◽

André Wachau ◽

Frank Säuberlich ◽

Yvonne Gassenbauer ◽

...

Keyword(s):

Fermi Level ◽

Work Function ◽

Energy Band ◽

Transparent Conducting Oxides ◽

Band Alignment ◽

Conducting Oxides ◽

Transparent Conducting

Download Full-text

Characterization of Spatial Distribution of Trap Across the Substrate in Metal-Insulator-Semiconductor Structure with Band Bending Effect

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19391 ◽

2021 ◽

Vol 21 (8) ◽

pp. 4315-4319

Author(s):

Jintae Yu ◽

Han Bin Yoo ◽

Hae Sung Kim ◽

Ji Hee Ryu ◽

Sung-Jin Choi ◽

...

Keyword(s):

Spatial Distribution ◽

Fermi Level ◽

Energy Band ◽

Vertical Direction ◽

Interface State ◽

Vertical Position ◽

Trap Level ◽

Band Bending ◽

Bending Effect

We report the technique of trap distribution extraction according to the vertical position of the substrate in the p-MOSFET. This study was conducted on a single device. This technique is an experimental method. Ctrap was extracted based on the deep depletion C–V characteristics. In VFB, the trap level is neutral. When bias is applied, the energy band bends, resulting in modulation of the quasi-Fermi level. The area created by the bending of the energy band is equal to the area created by the Fermi level modulation. The trap level existing in this area becomes charged. Considering this, the spatial distribution of Trap was extracted. The trap extracted by the proposed method has a maximum value at the interface, rapidly decreases, and is distributed up to 8 nm in the vertical direction. The study of trap spatial distribution is expected to be applicable to the separation of trap interface state and bulk trap extraction later.

Download Full-text

Optical and Electronic Energy Band Properties of Nb-Doped β-Ga2O3 Crystals

Crystals ◽

10.3390/cryst11020135 ◽

2021 ◽

Vol 11 (2) ◽

pp. 135

Author(s):

Xianjian Long ◽

Wenlong Niu ◽

Lingyu Wan ◽

Xian Chen ◽

Huiyuan Cui ◽

...

Keyword(s):

Fermi Level ◽

Conduction Band ◽

Energy Band ◽

Doping Level ◽

Electronic Energy ◽

Energy Structure ◽

Electrical Characteristics ◽

Floating Zone ◽

Nb Doping ◽

Electronic Energy Band

Systemic investigations are performed to comprehend the structural, optical, and electrical characteristics of four niobium (Nb) doped β-Ga2O3 crystals (β-Ga2O3:Nb) grown by the optical floating zone (OFZ) method. All of the β-Ga2O3:Nb crystals revealed monoclinic phases and good crystalline qualities. While the different Nb doped (i.e., 0.0001 mol%, 0.01 mol%, 0.1 mol% and 0.5 mol%) samples exhibited slightly changed bandgap energies Eg (≡ 4.72 eV, 4.73 eV, 4.81 eV, 4.68 eV)—the luminescence features indicated distinctive defect levels—affecting the electronic energy structure significantly. By increasing the Nb doping level from 0.0001 mol% to 0.1 mol%, the Fermi level (EF) moves closer to the bottom of the conduction band. For the sample with Nb doping 0.5 mol%—no further improvement is noticed in the electronic properties. Finally, the energy band diagrams of four samples are given.

Download Full-text

Механизм генерирования донорно-акцепторных пар при сильном легировании n-ZrNiSn акцепторной примесью Ga

Физика и техника полупроводников ◽

10.21883/ftp.2018.03.45614.8573 ◽

2018 ◽

Vol 52 (3) ◽

pp. 311

Author(s):

В.А. Ромака ◽

P.-F. Rogl ◽

D. Frushart ◽

D. Kaczorowski

Keyword(s):

Fermi Level ◽

Density Distribution ◽

Spatial Arrangement ◽

Structural Defects ◽

Acceptor Impurity ◽

Simultaneous Generation ◽

Donor Acceptor ◽

Heavily Doped ◽

Heavy Doping ◽

Rate Of Movement

AbstractThe nature of the mechanism of the simultaneous generation of donor–acceptor pairs under heavy doping of n -ZrNiSn intermetallic semiconductor with the Ga acceptor impurity is established. Such spatial arrangement in the crystal lattice of ZrNiSn_1– x Ga_ x is found when the rate of movement of the Fermi level εF found from calculations of the density distribution of electron states coincides with that experimentally established from dependences lnρ(1/ T ). It is shown that when the Ga impurity atom (4 s ^24 p ^1) occupies the 4 b sites of Sn atoms (5 s ^25 p ^2), structural defects of both acceptor nature and donor nature in the form of vacancies in the 4 b site are simultaneously generated. The results are discussed in the scope of the Shklovskii–Efros model of a heavily doped and compensated semiconductor.

Download Full-text