Transient Photocurrent Spectroscopy of Trap Levels in Ultra-Thin SiO2 Films

1996 ◽  
Vol 428 ◽  
Author(s):  
Y. Miura ◽  
S. Fujieda
Keyword(s):  
Cross Section ◽  
Monochromatic Light ◽  
Electron Trap ◽  
External Circuit ◽  
Broad Distribution ◽  
Transient Photocurrent ◽  
Photocurrent Spectroscopy ◽  
Optical Cross Section ◽  
Tunneling Injection ◽  
Trap Levels

AbstractStress-induced trap levels near Si/SiO2 interfaces for MOS diodes with 10 imi-thick oxides are investigated by measuring the transient photocurrent, which depends on the incident photon energy. The electron trap levels are filled by tunneling injection, and the electrons are depopulated by monochromatic light irradiation. The transient photocurrent, which is measured as an external circuit current, decays exponentially with time. Based on a proposed detrapping model, the optical cross section is estimated to be about 1×10−17 cm2 for hv=2−3 eV. The obtained photo-accessible trap density has a broad distribution at around hv=2.5 eV.

Evaluation of Electron Trap Levels in SOI Buried Oxides by Transient Photocurrent Spectroscopy

1998 ◽  
Vol 37 (Part 1, No. 3B) ◽  
pp. 1274-1277 ◽  
Author(s):  
Yoshinao Miura ◽  
Kouichi Hamada ◽  
Tomohisa Kitano ◽  
Atsushi Ogura
Keyword(s):  
Electron Trap ◽  
Transient Photocurrent ◽  
Photocurrent Spectroscopy ◽  
Trap Levels

Electronic Transitions in Mixed Phase Crystalline/Amorphous Silicon in the Low Crystalline Fraction Regime

1999 ◽  
Vol 557 ◽  
Author(s):  
J. David Cohen ◽  
Daewon Kwon ◽  
Chih-Chiang Chen ◽  
Hyun-Chul Jin ◽  
Eric Hollar ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Cross Section ◽  
Optical Transition ◽  
Electronic Transitions ◽  
Crystalline Fraction ◽  
Silicon Matrix ◽  
Transient Photocurrent ◽  
Dc Reactive Magnetron Sputtering ◽  
Optical Cross Section ◽  
Low Crystalline

AbstractAmorphous silicon films were prepared by dc reactive magnetron sputtering under conditions approaching the phase transition to microcrystallinity. Using TEM imaging these films were found to contain clusters of 5 to 50 nm sized Si crystallites embedded in an amorphous silicon matrix. Photocapacitance and transient photocurrent sub-band-gap optical spectra of this material appear to consist of a superposition of a spectrum typical of amorphous silicon together with an optical transition, with a threshold near 1. 1eV, that exhibits a very large optical cross section. This transition arises from valence band electrons being optically inserted into empty levels lying within the amorphous silicon mobility gap. Using modulated photocurrent methods we have determined that these states also dominate the electron deep trapping in this material. We argue that these states arise from defects at the crystalline-amorphous boundary.

Transient Photocurrent Response of Dye-Sensitized Porous Nanocrys1Alline TiO2 Electrodes

1996 ◽  
Vol 452 ◽  
Author(s):  
Albert Goossens ◽  
G. K. Boschloo ◽  
J. Schoonman
Keyword(s):  
Electron Trap ◽  
Photocurrent Response ◽  
Time Resolved ◽  
Oxide Semiconductors ◽  
Dye Sensitized ◽  
Transient Photocurrent ◽  
Photocurrent Spectroscopy ◽  
Electron Migration ◽  
Intensity Modulated Photocurrent Spectroscopy ◽  
Nanostructured Metal

AbstractIn order to investigate the fundamentals of electron migration in nanostructured metal-oxide semiconductors, the transient photocurrent response of dye-sensitized porous nanocrystalline TiO2 is studied. The time-resolved photocurrent response at light steps or pulses shows a faster transient upon increasing the light intensity. Intensity-modulated photocurrent spectroscopy (IMPS) reveals that the transient photocurrent is dominated by two time constants, i.e. the geometrical one and a characteristic time related to electron trapping. A theoretical model is derived in which the occupation dynamics of a single electron trap is considered using Shockley-Read-Hall kinetics. The geometrical RC time of the electrode is also included. Excellent agreement between this model and the measured IMPS spectra is obtained.

Dependence of the optical cross section of interface states on the photon energy at Si-SiO2 structures

1986 ◽  
Vol 168 (1-3) ◽  
pp. 665-671 ◽  
Author(s):  
A. Herms ◽  
J.R. Morante ◽  
J. Samitier ◽  
A. Cornet ◽  
P. Cartujo ◽  
...  
Keyword(s):  
Cross Section ◽  
Photon Energy ◽  
Interface States ◽  
Optical Cross Section

The Defect Structure of BaTiO3 Thin Films

1993 ◽  
Vol 310 ◽  
Author(s):  
L.A. Wills ◽  
B.W. Wessels
Keyword(s):  
Thin Films ◽  
Cross Section ◽  
Defect Structure ◽  
Oxygen Vacancies ◽  
Vacuum Annealing ◽  
Deep Level ◽  
Energy Levels ◽  
The Other ◽  
Optical Cross Section ◽  
Impurity Defects

AbstractThe defect structure of BaTiO3 thin films grown on (100) Si was examined using transient photocapacitance spectroscopy. The concentration, optical cross section and associated energy levels of both native and impurity defects in as-grown and annealed BaTiO3 films were evaluated. Deep level defects withpeak energies of Ev+1.8, Ev+2.4, Ev+2.7, Ev+3.0-3.1 and Ev+3.2-3.3 eV were observed in the as-grown films. Upon vacuum annealing, the concentration of the traps at Ev+3.0 and Ev+3.2 eV increased while the concentration of the traps at Ev+ 1.8 and Ev+2.4 eV decreased. The levels at Ev+3.0-3.1 and Ev+3.2-3.3 eV are attributed to oxygen vacancies. The other levels are tentatively ascribed to Fe and Fe related defects.

PHOTOIONIZATION CROSS SECTION OF THE 2.5 eV ELECTRON TRAP IN SiO2

1980 ◽  
pp. 142-146 ◽  
Author(s):  
D.D. Rathman ◽  
F.J. Feigl ◽  
S.R. Butler ◽  
W.B. Fowler
Keyword(s):  
Cross Section ◽  
Photoionization Cross Section ◽  
Electron Trap

Untersuchungen zur Wirkung von monochromatischer Vakuum-UV-Strahlung auf DNS

1969 ◽  
Vol 24 (6) ◽  
pp. 722-728 ◽  
Author(s):  
K. U. Berger
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Electron Emission ◽  
Vacuum Ultraviolet ◽  
Monochromatic Light ◽  
Ionization Probability ◽  
Thin Layers ◽  
Inactivation Mechanism ◽  
Grating Monochromator ◽  
Vacuum Uv

Inactivation cross sections of infectious ΦΧ-174-DNA in the extreme vacuum-ultraviolet were determined by irradiation of thin layers with monochromatic light down to 584 Å by means of a powerful grating-monochromator, the elements of which are described. Comparison of inactivation and light-induced electron emission shows that light of quantum energies below 7 eV inactivates by excitation only, whereas above 10.2 eV ionization is the predominant inactivation mechanism. Because of the satisfactory agreement of the curves for inactivation and electron emission, it is conducted that the remarkable increase of the inactivation cross section in the region of the short wavelength vacuum-uv is due to increasing ionization probability.

Sign in / Sign up

Export Citation Format

Share Document