scholarly journals Electron Band Alignment at Interfaces of Semiconductors with Insulating Oxides: An Internal Photoemission Study

2014 ◽  
Vol 2014 ◽  
pp. 1-30 ◽  
Author(s):  
Valeri V. Afanas'ev
Keyword(s):  
Valence Band ◽  
High Mobility ◽  
Band Alignment ◽  
Photoemission Spectroscopy ◽  
Light Elements ◽  
Bandgap Width ◽  
Electron Band ◽  
Internal Photoemission ◽  
Wide Gap ◽  
Photoemission Study

Evolution of the electron energy band alignment at interfaces between different semiconductors and wide-gap oxide insulators is examined using the internal photoemission spectroscopy, which is based on observations of optically-induced electron (or hole) transitions across the semiconductor/insulator barrier. Interfaces of various semiconductors ranging from the conventional silicon to the high-mobility Ge-based (Ge,Si1-xGex,Ge1-xSnx) andAIIIBVgroup (GaAs,InxGa1-xAs, InAs, GaP, InP, GaSb, InSb) materials were studied revealing several general trends in the evolution of band offsets. It is found that in the oxides of metals with cation radii larger than≈0.7 Å, the oxide valence band top remains nearly at the same energy (±0.2 eV) irrespective of the cation sort. Using this result, it becomes possible to predict the interface band alignment between oxides and semiconductors as well as between dissimilar insulating oxides on the basis of the oxide bandgap width which are also affected by crystallization. By contrast, oxides of light elements, for example, Be, Mg, Al, Si, and Sc exhibit significant shifts of the valence band top. General trends in band lineup variations caused by a change in the composition of semiconductor photoemission material are also revealed.

Band alignment at CdS/wide-band-gap Cu(In,Ga)Se2 hetero-junction by using PES/IPES

2005 ◽  
Vol 865 ◽  
Author(s):  
S.H. Kong ◽  
H. kashiwabara ◽  
K. Ohki ◽  
K. Itoh ◽  
T. Okuda ◽  
...  
Keyword(s):  
Band Gap ◽  
Conduction Band ◽  
Ion Beam ◽  
Wide Band ◽  
Valence Band Maximum ◽  
Conduction Band Minimum ◽  
Band Alignment ◽  
Interface Region ◽  
Photoemission Spectroscopy ◽  
Wide Gap

AbstractDirect characterization of band alignment at chemical bath deposition (CBD)-CdS/Cu0.93 (In1-xGax)Se2 has been carried out by photoemission spectroscopy (PES) and inverse photoemission spectroscopy (IPES). Ar ion beam etching at the condition of the low ion kinetic energy of 350 eV yields a removal of surface contamination as well as successful measurement of the intrinsic properties of each layer and the interfaces. Especially interior regions of the wide gap CIGS layers with a band gap of 1.4 ∼ 1.6 eV were successfully exposed. IPES spectra revealed that the conduction band offset (CBO) at the interface region of the wide gap CIGS with x = 0.60 and 0.75 was negative, where the conduction band minimum of CdS was lower than that of CIGS. It was also observed that the energy spacing between conduction band minimum (CBM) of CdS layer and valence band maximum (VBM) of Cu0.93(In0.25Ga0.75)Se2 layer at interface region was no wider than that of the interface over the Cu0.93(In0.60Ga0.40)Se2 layer.

Tunnel field-effect transistor heterojunction band alignment by internal photoemission spectroscopy

2012 ◽  
Vol 100 (10) ◽  
pp. 102104 ◽  
Author(s):  
Qin Zhang ◽  
Guangle Zhou ◽  
Huili G. Xing ◽  
Alan C. Seabaugh ◽  
Kun Xu ◽  
...  
Keyword(s):  
Field Effect ◽  
Field Effect Transistor ◽  
Band Alignment ◽  
Photoemission Spectroscopy ◽  
Internal Photoemission ◽  
Effect Transistor ◽  
Tunnel Field Effect Transistor

(Invited) Electron Band Alignment at Ge/Oxide and AIII-BV/Oxide Interfaces from Internal Photoemission Experiments

2013 ◽  
Vol 58 (7) ◽  
pp. 311-316 ◽  
Author(s):  
V. V. Afanas'ev ◽  
H.- Y. Chou ◽  
M. Houssa ◽  
A. Stesmans
Keyword(s):  
Band Alignment ◽  
Oxide Interfaces ◽  
Electron Band ◽  
Internal Photoemission

A Photoemission Study of the Epitaxial Growth of Si on Gap(110)

1987 ◽  
Vol 94 ◽  
Author(s):  
David W. Niles ◽  
Ming Tang ◽  
Hartmut Höchst
Keyword(s):  
Fermi Level ◽  
Epitaxial Growth ◽  
Valence Band ◽  
Surface State ◽  
Photoemission Spectroscopy ◽  
Fermi Level Position ◽  
Ultraviolet Photoemission Spectroscopy ◽  
Photoemission Study ◽  
Valence Band Discontinuity

ABSTRACTWe have used angular resolved ultraviolet photoemission spectroscopy to study the epitaxial growth of Si on GaP(110). Surface state emission obscures the top of the valence band (TVB). The Fermi level for the clean GaP(110) surface is 1.20±0.05eV above the TVB. 1ML (monolayer) of Si pins the Fermi level position at 1.40±0.05eV above the TVB. Further deposition of Si leads to a valence band discontinuity ΔEv=1.07 ±0.10eV.

Direct Optical Measurement of the valence band offset of p+ Si1−x−yGexCy/p− Si (100) by Heterojunction Internal Photoemission

1998 ◽  
Vol 533 ◽  
Author(s):  
C. L. Chang ◽  
L. P. Rokhinson ◽  
J. C. Sturm
Keyword(s):  
Valence Band ◽  
Optical Measurement ◽  
Chemical Vapor ◽  
Band Alignment ◽  
Band Offset ◽  
Valence Band Offset ◽  
Strained Si ◽  
Internal Photoemission ◽  
Capacitance Voltage ◽  
Absorption Measurements

AbstractOptical absorption measurements have been performed to study the effect of carbon on the valence band offset of compressively strained p+ Si1−x−yGexCy/(100) p− Si heterojunction internal photoemission structures grown by Rapid Thermal Chemical Vapor Deposition (RTCVD) with substitutional carbon levels up to 2.5%. Results indicated that carbon decreased the valence band offset by 26 ± 1 meV/ %C. Results from optical measurement in this study agreed with previous data from capacitance-voltage measurements. Based on previous reports of carbon effect on the bandgap of compressively strained Si1−x−yGexCy, our work suggests that the effect of carbon incorporation on the band alignment of Si1−x−yGexCy/Si is to reduce the valence band offset, with a negligible effect on the conduction band alignment.

HIGH SPATIAL RESOLUTION SOFT X-RAY PHOTOEMISSION STUDY OF WO3 THIN FILMS

2002 ◽  
Vol 09 (01) ◽  
pp. 375-380 ◽  
Author(s):  
L. LOZZI ◽  
M. PASSACANTANDO ◽  
S. SANTUCCI ◽  
S. LA ROSA ◽  
N. YU. SVETCHNIKOV
Keyword(s):  
Valence Band ◽  
Film Surface ◽  
Photoemission Spectroscopy ◽  
X Ray ◽  
Thin Film Surface ◽  
High Lateral Resolution ◽  
Band Spectra ◽  
Photoemission Study ◽  
First Time ◽  
Wo3 Thin Films

WO 3 thin film surface chemical composition has been studied by means of high resolution soft X-ray photoemission spectroscopy. Valence band and W 4f core levels have been analyzed on different sample positions and high lateral resolution images have been acquired. The valence band spectra have shown for the first time a marked increase of the W 5d density of state at the Fermi level, indicating the presence of metallic tungsten on the surface. This has been confirmed by the W 4f signal, which presents both metallic and oxidized phases. For the first time, spectromicroscopy on core states has clearly evidenced the presence of nonstoichiometric areas and a spatial localization of W 4+ states on the surface.

Sign in / Sign up

Export Citation Format

Share Document