Preparation and electrical properties of heterojunctions of ZnO on Zn3P2 and CdTe

1989 ◽  
Vol 67 (4) ◽  
pp. 448-455 ◽  
Author(s):  
M. Ginting ◽  
J. D. Leslie
Keyword(s):  
Single Crystal ◽  
Deep Level ◽  
Photovoltaic Performance ◽  
Polycrystalline Film ◽  
Metal Insulator ◽  
Measurement And Analysis ◽  
Transient Spectroscopy ◽  
P Type ◽  
Zno Single Crystal ◽  
High Series

"Heterojunctions" have been fabricated by the reactive evaporation of thin film n-type ZnO onto p-type single crystal Zn3P2, polycrystalline films of Zn3P2, and single crystal CdTe. The photovoltaic response of the n-ZnO – single crystal p-CdTe devices was good, that of the n-ZnO – single crystal p-Zn3P2 devices was poor, and that of the n-ZnO – p-Zn3P2 polycrystalline film devices was nonexistent. The ideality factor n of all devices studied was greater than two. On the basis of 1/C2 vs. V results, the n-ZnO – single crystal p-Zn3P2 devices behaved most like Schottky barrier devices, whereas the n-ZnO – p-Zn3P2 polycrystalline film devices, and the n-ZnO – p-single crystal CdTe "heterojunctions" behaved most like metal–insulator–semiconductor devices. The high series resistance of all devices had to be considered in the measurement and analysis, and it limited the photovoltaic performance. Deep-level transient spectroscopy measurements indicated majority (hole) traps in the CdTe and Zn3P2 with activation energies in agreement with previous measurements in the literature.

Impact of the Gate Material on the Deep Levels in a-Si:H/c-Si Metal-Insulator-Semiconductor Capacitors

2015 ◽  
Vol 242 ◽  
pp. 61-66
Author(s):  
Eddy Simoen ◽  
Valentina Ferro ◽  
Barry O’Sullivan
Keyword(s):  
Minority Carrier ◽  
Crystalline Silicon ◽  
Deep Level ◽  
Silicon Layer ◽  
Si Substrate ◽  
Metal Insulator ◽  
Metal Insulator Semiconductor ◽  
Transient Spectroscopy ◽  
P Type ◽  
Mis Capacitors

Deep Level Transient Spectroscopy (DLTS) has been applied to Metal-Insulator-Semiconductor (MIS) capacitors, consisting of a p+ or n+ a-Si:H gate on an intrinsic i-a-Si:H passivation layer deposited on crystalline silicon n-or p-type substrates. It is shown that the type of gate has a pronounced impact on the obtained spectra, whereby both the kind of defects (dangling bonds at the a-Si:H/(100) c-Si interface (Pb0 defects) or in the amorphous silicon layer (D defects) and their relative importance (peak amplitude) may be varied. The highest trap densities have been found for the p+ a-Si:H gate capacitors on an n-type Si substrate. In addition, the spectra may exhibit unexpected negative peaks, suggesting minority carrier capture. These features are tentatively associated with interface states at the p+ or n+ a-Si:H/i-a-Si:H interface. Their absence in Al-gate capacitors is in support of this hypothesis.

Hydrogen Passivation of Defects in Electron Irradiated Polycrystalline Silicon Solar Cells

1995 ◽  
Vol 378 ◽  
Author(s):  
R.R. Bilyalov ◽  
B.M. Abdurakhmanov
Keyword(s):  
Solar Cells ◽  
Polycrystalline Silicon ◽  
Deep Level ◽  
Photovoltaic Performance ◽  
Silicon Solar Cells ◽  
Silicon Substrates ◽  
Hydrogen Passivation ◽  
Boron Doped ◽  
Transient Spectroscopy ◽  
P Type

AbstractThe effect of hydrogen passivation on photovoltaic performance of 1 MeV electron irradiated polycrystalline cast silicon solar cells is described. These cells were processed on cast p-type boron doped polycrystalline silicon substrates using standard technology. Passivation was made by low-energy hydrogen ion implantation on the front side. Cells performance was measured as a function of fluence, and it was found that the hydrogenated cell had the higher radiation resistance.Defect behavior were studied using deep level transient spectroscopy and infra-red spectroscopy. It was shown that the concentration of vacancies (Ec −0,09 eV), divacancies (Ec −0,23 eV) and A-centers (Ec −0,18 eV) is significantly lower in hydrogenated samples. This consistency strengthens the belief that hydrogen interacts with vacancy-type defects to prevent formation of the secondary radiation defects. It is confirmed by IR-measurements.

A DLTS study of a ZnO microwire, a thin film and bulk material

2014 ◽  
Vol 1633 ◽  
pp. 51-54
Author(s):  
Florian Schmidt ◽  
Peter Schlupp ◽  
Stefan Müller ◽  
Christof Peter Dietrich ◽  
Holger von Wenckstern ◽  
...  
Keyword(s):  
Thin Film ◽  
Single Crystal ◽  
Deep Level ◽  
Bulk Material ◽  
Intrinsic Defect ◽  
Growth Technique ◽  
Current Voltage ◽  
Common Opinion ◽  
Transient Spectroscopy ◽  
Zno Single Crystal

ABSTRACTWe have investigated the electrical properties of a ZnO microwire grown by carbo-thermal evaporation, a ZnO thin film grown by pulsed-laser deposition on an a-plane sapphire, and a hydrothermally grown Zn-face ZnO single crystal (Tokyo Denpa Co. Ltd.). The samples were investigated by means of current-voltage measurements, capacitance-voltage measurements, and deep-level transient spectroscopy.The defects T2 [1,2] and E3 [1,3,4] were identified in all three sample types. Additionally, in the single crystal and thin film samples E64 [5] and E4 [1] were detected. These findings support the common opinion that T2 is an intrinsic defect since it is found in all the samples investigated and thus its occurrence is not related to any growth technique.

Spectrum of Defect States in Porous Organic Low-k Dielectric Films, Annealed in Argon and Nitrogen

2003 ◽  
Vol 766 ◽  
Author(s):  
V. Ligatchev ◽  
T.K.S. Wong ◽  
T.K. Goh ◽  
Rusli Suzhu Yu
Keyword(s):  
Deep Level ◽  
Dielectric Films ◽  
Silicon Substrates ◽  
Reverse Bias Voltage ◽  
Defect States ◽  
Single Side ◽  
Sandwich Type ◽  
Transient Spectroscopy ◽  
P Type ◽  
Spectrum Deconvolution

AbstractDefect spectrum N(E) of porous organic dielectric (POD) films is studied with capacitance deep-level-transient-spectroscopy (C-DLTS) in the energy range up to 0.7 eV below conduction band bottom Ec. The POD films were prepared by spin coating onto 200mm p-type (1 – 10 Δcm) single-side polished silicon substrates followed by baking at 325°C on a hot plate and curing at 425°C in furnace. The film thickness is in the 5000 – 6000 Å range. The ‘sandwich’ -type NiCr/POD/p-Si/NiCr test structures showed both rectifying DC current-voltage characteristics and linear 1/C2 vs. DC reverse bias voltage. These confirm the applicability of the C-DLTS technique for defect spectrum deconvolution and the n-type conductivity of the studied films. Isochronal annealing (30 min in argon or 60 min in nitrogen) has been performed over the temperature range 300°C - 650°C. The N(E) distribution is only slightly affected by annealing in argon. However, the distribution depends strongly on the annealing temperature in nitrogen ambient. A strong N(E) peak at Ec – E = 0.55 – 0.60 eV is detected in all samples annealed in argon but this peak is practically absent in samples annealed in nitrogen at Ta < 480°C. On the other hand, two new peaks at Ec – E = 0.12 and 0.20 eV appear in the N(E) spectrum of the samples annealed in nitrogen at Ta = 650°C. The different features of the defect spectrum are attributed to different interactions of argon and nitrogen with dangling carbon bonds on the intra-pore surfaces.

scholarly journals Impact of Hydrogenation on Electrical Properties of NiSi2 Precipitates in Silicon

2005 ◽  
Vol 108-109 ◽  
pp. 279-284 ◽  
Author(s):  
O.F. Vyvenko ◽  
N.V. Bazlov ◽  
M.V. Trushin ◽  
A.A. Nadolinski ◽  
Michael Seibt ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Deep Level Transient Spectroscopy ◽  
Molecular Hydrogen ◽  
Deep Level ◽  
Hydrogen Plasma ◽  
Extended Defects ◽  
Transient Spectroscopy ◽  
P Type ◽  
Plasma Hydrogenation ◽  
Type Sample

Influence of annealing in molecular hydrogen as well as of treatment in hydrogen plasma (hydrogenation) on the electrical properties of NiSi2 precipitates in n- and p-type silicon has been studied by means of deep level transient spectroscopy (DLTS). Both annealing and hydrogenation gave rise to noticeable changes of the shape of the DLTS-peak and of the character of its dependence on the refilling pulse duration that according to [1] allows one to classify the electronic states of extended defects as “band-like” or “localized”. In both n- and p-type samples DLTS-peak in the initial as quenched samples showed bandlike behaviour. Annealing or hydrogenation of n-type samples converted the band-like states to the localised ones but differently shifted the DLTS-peak to higher temperatures. In p-type samples, the initial “band-like” behaviour of DLTS peak remained qualitatively unchanged after annealing or hydrogenation. A decrease of the DLTS-peak due to precipitates and the appearance of the peaks due to substitutional nickel and its complexes were found in hydrogenated p-type sample after removal of a surface layer of 10-20µm.

Conductance Transients Study of Slow Traps in Al/SiNx:H/Si and Al/SiNx:H/InP Metal-Insulator-Semiconductor Structures

1997 ◽  
Vol 500 ◽  
Author(s):  
S. Dueñas ◽  
R. Peláez ◽  
E. Castán ◽  
J. Barbolla ◽  
I. Mártil ◽  
...  
Keyword(s):  
Silicon Nitride ◽  
Electron Cyclotron Resonance ◽  
Deep Level ◽  
Perfect Agreement ◽  
Metal Insulator ◽  
Metal Insulator Semiconductor ◽  
Semiconductor Interfaces ◽  
Interfacial Defects ◽  
Transient Spectroscopy ◽  
Resonance Plasma

ABSTRACTWe have obtained Al/SiNx:H/Si and Al/SiNx:H/InP Metal-Insulator-Semiconductor devices by directly depositing silicon nitride thin films on silicon and indium phosphide wafers by the Electron Cyclotron Resonance Plasma method at 200°C. The electrical properties of the structures were first analyzed by Capacitance-Voltage measurements and Deep-Level Transient Spectroscopy (DLTS). Some discrepancies in the absolute value of the interface trap densities were found. Later on, Admittance measurements were carried out and room and low temperature conductance transients in the silicon nitride/semiconductor interfaces were found. The shape of the conductance transients varied with the frequency and temperature at which they were obtained. This behavior, as well as the previously mentioned discrepancies, are explained in terms of a disorder-induced gap-state continuum model for the interfacial defects. A perfect agreement between experiment and theory is obtained proving the validity of the model.

Reactive-Ion-Etching Induced Deep Levels Observed in n-Type and p-Type 4H-SiC

2010 ◽  
Vol 645-648 ◽  
pp. 759-762
Author(s):  
Koutarou Kawahara ◽  
Giovanni Alfieri ◽  
Michael Krieger ◽  
Tsunenobu Kimoto
Keyword(s):  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Reactive Ion Etching ◽  
Deep Levels ◽  
Total Density ◽  
Ion Etching ◽  
Initial Concentration ◽  
Grown Sample ◽  
Transient Spectroscopy ◽  
P Type

In this study, deep levels are investigated, which are introduced by reactive ion etching (RIE) of n-type/p-type 4H-SiC. The capacitance of as-etched p-type SiC is remarkably small due to compensation or deactivation of acceptors. These acceptors can be recovered to the initial concentration of the as-grown sample after annealing at 1000oC. However, various kinds of defects remain at a total density of ~5× 1014 cm-3 in a surface-near region from 0.3 μm to 1.0 μm even after annealing at 1000oC. The following defects are detected by Deep Level Transient Spectroscopy (DLTS): IN2 (EC – 0.35 eV), EN (EC – 1.6 eV), IP1 (EV + 0.35 eV), IP2 (HS1: EV + 0.39 eV), IP4 (HK0: EV + 0.72 eV), IP5 (EV + 0.75 eV), IP7 (EV + 1.3 eV), and EP (EV + 1.4 eV). These defects generated by RIE can be significantly reduced by thermal oxidation and subsequent annealing at 1400oC.

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