Surface Phenomena of the Thin Diamond-Like Carbon Films

1998 ◽  
Vol 555 ◽  
Author(s):  
V. I. Polyakov ◽  
A. I. Rukovishnikov ◽  
A. V. Khomich ◽  
B. L. Druz ◽  
D. Kania ◽  
...  
Keyword(s):  
Deep Level ◽  
Carbon Films ◽  
Diamond Like Carbon ◽  
Surface Phenomena ◽  
Capacitance Voltage ◽  
Planar Array ◽  
Strong Surface ◽  
Transient Spectroscopy ◽  
Quartz Substrates ◽  
Dlts Spectra

AbstractDiamond-like carbon films (DLC) 10–40 nm thick were deposited on quartz substrates on an interdigitated planar array of 20 μm Ni electrodes already prepared by lithographic techniques. The influence of the adsorbed molecules onte electrical properties of the thin DLC films was investigated. Current and capacitance-voltage characteristics were examined. Charge-based deep level transient spectroscopy (Q-DLTS) was used for study of adsorption and desorption processes. The strong sensitivity of Q-DLTS spectra to the presence of the vapor water and isopropyl alcohol was found. For example, the Q-DLTS signal for some deposited DLC film was changed more then in order in presence of the water vapor. Such strong surface phenomena of the thin DLC films may be exploited in novel gas sensor devices.

Dlts and CV Analysis of Doped and N-Implanted GaN

1996 ◽  
Vol 423 ◽  
Author(s):  
D. Haase ◽  
M. Schmid ◽  
A. Dörnen ◽  
V. Härle ◽  
H. Bolay ◽  
...  
Keyword(s):  
Carrier Concentration ◽  
Deep Level ◽  
Implantation Dose ◽  
Nitrogen Implantation ◽  
Capacitance Voltage ◽  
Defect Levels ◽  
Transient Spectroscopy ◽  
Additional Defect ◽  
Cv Measurements ◽  
Dlts Spectra

AbstractWe studied by deep level transient spectroscopy (DLTS) and capacitance-voltage (CV) measurements the effects of doping (Zn, S), nitrogen implantation and annealing of n-type GaN grown on sapphire by MOVPE. The DLTS spectra of the as grown samples show two defect levels which are assumed to be identical with recently reported levels [10, 11]. In N-implanted GaN a third level is introduced which is not detectable in our as grown samples. This levels concentration follows the increasing N-implantation density. The depth profiles of its concentration correlate with the distribution of implantation defects expected from Monte-Carlo simulation. After annealing at 900°C for 60s the additional defect level vanishes. The DLTS spectrum then resembles those of annealed as grown samples. The n-type carrier concentration (CV measurements) increases in samples with low N-implantation dose. This implantation effect can be removed also with the RTA step. The increasing carrier concentration provides evidence that the N vacancy is a donor in GaN. For Zn and S doped GaN deep defect levels has been found, which are reported here.

Investigation of Deep-Level Defects Lateral Distribution in Active Layers of Multicrystalline Silicon Solar Cells

MRS Advances ◽  
2017 ◽  
Vol 2 (53) ◽  
pp. 3141-3146 ◽  
Author(s):  
Vladimir G. Litvinov ◽  
Alexander V. Ermachikhin ◽  
Dmitry S. Kusakin ◽  
Nikolay V. Vishnyakov ◽  
Valery V. Gudzev ◽  
...  
Keyword(s):  
Solar Cells ◽  
Deep Level ◽  
Lateral Distribution ◽  
Silicon Solar Cells ◽  
Characteristics Method ◽  
Active Layers ◽  
Capacitance Voltage ◽  
Transient Spectroscopy ◽  
P Type ◽  
Dlts Spectra

ABSTRACTThe influence of deep level defects lateral distribution in active layers of multicrystalline Si-based standard solar cells is investigated. Multicrystalline p-type Si wafers with 156×156 mm dimensions and 200 μm thickness were used for SCs preparation. One type of solar cells with conversion efficiency 20.4% was studied using capacitance voltage characteristics method (C-V) and by current deep level transient spectroscopy (I-DLTS). From various places along the diagonal of solar cell’s substrate with 20.4% efficiency nine pieces with an area ∼20 mm2 were extracted and studied. I-DLTS spectra of the five pieces from solar cell were measured. The features of deep levels defects concentration lateral distribution along the SC’s surface were studied.

scholarly journals Влияние глубоких уровней дислокаций в гетероэпитаксиальных InGaAs/GaAs и GaAsSb/GaAs p-i-n-структурах на время релаксации неравновесных носителей

2018 ◽  
Vol 52 (2) ◽  
pp. 177
Author(s):  
М.М. Соболев ◽  
Ф.Ю. Солдатенков
Keyword(s):  
Cross Sections ◽  
Thermal Activation ◽  
Deep Level ◽  
Relaxation Times ◽  
Misfit Dislocations ◽  
Deep Acceptor ◽  
Capacitance Voltage ◽  
Transient Spectroscopy ◽  
Dlts Spectra ◽  
Nonequilibrium Carriers

AbstractThe results of an experimental study of the capacitance–voltage ( C – V ) characteristics and deep-level transient spectroscopy (DLTS) spectra of p ^+– p ^0– i – n ^0 homostructures based on undoped dislocationfree GaAs layers and InGaAs/GaAs and GaAsSb/GaAs heterostructures with homogeneous networks of misfit dislocations, all grown by liquid-phase epitaxy (LPE), are presented. Deep-level acceptor defects identified as HL 2 and HL 5 are found in the epitaxial p ^0 and n ^0 layers of the GaAs-based structure. The electron and hole dislocation-related deep levels, designated as, respectively, ED 1 and HD 3, are detected in InGaAs/GaAs and GaAsSb/GaAs heterostructures. The following hole trap parameters: thermal activation energies ( E _ t ), capture cross sections (σ_ p ), and concentrations ( N _ t ) are calculated from the Arrhenius dependences to be E _ t = 845 meV, σ _ p = 1.33 × 10^–12 cm^2, N _ t = 3.80 × 10^14 cm^–3 for InGaAs/GaAs and E _ t = 848 meV, σ _ p = 2.73 × 10^–12 cm^2, N _ t = 2.40 × 10^14 cm^–3 for GaAsSb/GaAs heterostructures. The concentration relaxation times of nonequilibrium carriers are estimated for the case in which dislocation-related deep acceptor traps are involved in this process. These are 2 × 10^–10 s and 1.5 × 10^–10 s for, respectively, the InGaAs/GaAs and GaAsSb/GaAs heterostructures and 1.6 × 10^–6 s for the GaAs homostructures.

scholarly journals Влияние нейтронного облучения на спектр дефектов с глубокими уровнями в GaAs, изготовленном методом жидкофазной эпитаксии в атмосфере водорода и аргона

2022 ◽  
Vol 56 (1) ◽  
pp. 53
Author(s):  
М.М. Соболев ◽  
Ф.Ю. Солдатенков
Keyword(s):  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Experimental Studies ◽  
Shallow Donor ◽  
Defect Clusters ◽  
Deep Traps ◽  
Capacitance Voltage ◽  
Before And After ◽  
Transient Spectroscopy ◽  
Different Doses

The results of experimental studies of capacitance– voltage characteristics, spectra of deep-level transient spectroscopy of graded high-voltage GaAs p+−p0−i−n0 diodes fabricated by liquid-phase epitaxy at a crystallization temperature of 900C from one solution–melt due to autodoping with background impurities, in a hydrogen or argon ambient, before and after irradiation with neutrons. After neutron irradiation, deep-level transient spectroscopy spectra revealed wide zones of defect clusters with acceptor-like negatively charged traps in the n0-layer, which arise as a result of electron emission from states located above the middle of the band gap. It was found that the differences in capacitance–voltage characteristics of the structures grown in hydrogen or argon ambient after irradiation are due to different doses of irradiation of GaAs p+−p0−i−n0 structures and different degrees of compensation of shallow donor impurities by deep traps in the layers.

Capacitance-voltage and deep-level-transient spectroscopy characterization of defects near SiO2/SiC interfaces

2011 ◽  
Vol 109 (6) ◽  
pp. 064514 ◽  
Author(s):  
A. F. Basile ◽  
J. Rozen ◽  
J. R. Williams ◽  
L. C. Feldman ◽  
P. M. Mooney
Keyword(s):  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Capacitance Voltage ◽  
Transient Spectroscopy

Deep Level Defect Studies in Mocvd-Grown InxGa1−sAs1−yNy Films Lattice-Matched to GaAs

1998 ◽  
Vol 535 ◽  
Author(s):  
Daewon Kwon ◽  
R. J. Kaplar ◽  
J. J. Boeckl ◽  
S. A. Ringel ◽  
A. A. Allerman ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Deep Level ◽  
Energy Levels ◽  
Resolution Limit ◽  
Defect States ◽  
Cross Sectional ◽  
Order Of Magnitude ◽  
Transient Spectroscopy ◽  
Lattice Matched ◽  
Dlts Spectra

AbstractDeep level defects in MOCVD-grown, unintentionally doped p-type InGaAsN films lattice matched to GaAs were investigated using deep level transient spectroscopy (DLTS) measurements. As-grown p-InGaAsN showed broad DLTS spectra suggesting that there exists a broad distribution of defect states within the band-gap. Moreover, the trap densities exceeded 1015 cm−3. Cross sectional transmission electron microscopy (TEM) measurements showed no evidence for threading dislocations within the TEM resolution limit of 107 cm−2. A set of samples was annealed after growth for 1800 seconds at 650 °C to investigate the thermal stability of the traps. The DLTS spectra of the annealed samples simplified considerably, revealing three distinct hole trap levels with energy levels of 0.10 eV, 0.23 eV, and 0.48 eV above the valence band edge with trap concentrations of 3.5 × 1014 cm−3, 3.8 × 1014 cm−3, and 8.2 × 1014 cm−3, respectively. Comparison of as-grown and annealed DLTS spectra showed that post-growth annealing effectively reduced the total trap concentration by an order of magnitude across the bandgap. However, the concentration of a trap with an energy level of 0.48 eV was not affected by annealing indicating a higher thermal stability for this trap as compared with the overall distribution of shallow and deep traps.

Deposition of Diamond-Like Carbon Films by Excimer Lasers Using Frozen Source Gases

1995 ◽  
Vol 397 ◽  
Author(s):  
Mitsugu Hanabusa ◽  
Kiyohito Tsujihara ◽  
Liu Zhengxin ◽  
Seiji Ishihara ◽  
Hironaga Uchida
Keyword(s):  
Carbon Films ◽  
Diamond Like Carbon ◽  
Degree Of Dissociation ◽  
Arf Laser ◽  
Frozen Gases ◽  
Quartz Substrates ◽  
High Degree ◽  
Power Densities ◽  
Deposited Films ◽  
Number Of Particles

ABSTRACTWe deposited diamond-like carbon (DLC) films, using frozen acetylene and acetone as the target of laser ablation. The frozen gases were dissociated by an ArF laser and a KrF laser. The DLC films were deposited on quartz substrates below 300°C. We measured the Raman spectra to identify the deposited films as DLC. The films showed the broad Raman peak at 1540 cm-1. The number of particles mixed into the deposits was controlled by laser power densities. By using the ArF laser for frozen acetylene we could reduce the hydrogen concentration in the films, which showed a high degree of dissociation of the source gas. The oxygen content was kept at the same level in the films deposited from frozen acetone as from frozen acetylene. The present results suggested the importance of energetic and charged species ejected from the frozen gas target.

C-V and DLTS Analyses of Trap-Induced Graded Junctions: The Case of Al+ Implanted JTE p+n 4H-SiC Diodes

2009 ◽  
Vol 615-617 ◽  
pp. 469-472
Author(s):  
Filippo Fabbri ◽  
Francesco Moscatelli ◽  
Antonella Poggi ◽  
Roberta Nipoti ◽  
Anna Cavallini
Keyword(s):  
Depth Distribution ◽  
Minority Carrier ◽  
Deep Level ◽  
Forward Bias ◽  
Depth Range ◽  
Standard Configuration ◽  
Carrier Traps ◽  
Transient Spectroscopy ◽  
Graded Junction ◽  
Dlts Spectra

Capacitance versus Voltage (C-V) and Deep Level Transient Spectroscopy (DLTS) measurements of Al+ implanted p+n diodes with Al+ implanted Junction Termination Extension are here studied. These diodes present C-V characteristics like graded junction for low forward bias values, i.e. > 0.4 V , or like abrupt junctions for large reverse bias, i.e. between 0.4V and -10V. The depth range of the graded junction, computed by the capacitance values, is much larger than the simulated tail of the ion implanted Al+ profile. DLTS spectra have been measured both in injection and standard configuration and always show minority carrier traps in the temperature range 0-300K. Three are the minority carrier related peaks, one attributed to the Al acceptor and the others to the D and D1 defects. The depth distribution of these hole traps will be discussed with respect to the apparent carrier concentration, obtained by C-V analysis.

Z1/2- and EH6-Center in 4H-SiC: Not Identical Defects ?

2012 ◽  
Vol 717-720 ◽  
pp. 251-254 ◽  
Author(s):  
Bernd Zippelius ◽  
Alexander Glas ◽  
Heiko B. Weber ◽  
Gerhard Pensl ◽  
Tsunenobu Kimoto ◽  
...  
Keyword(s):  
Activation Energy ◽  
Electric Field ◽  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Schottky Contacts ◽  
Double Peak ◽  
Carbon Vacancy ◽  
High Concentrations ◽  
Transient Spectroscopy ◽  
Dlts Spectra

Deep Level Transient Spectroscopy (DLTS) and Double-correlated DLTS (DDLTS) measurements have been conducted on Schottky contacts fabricated on n-type 4H-SiC epilayers using different contact metals in order to separate the EH6- and EH7-centers, which usually appear as a broad double peak in DLTS spectra. The activation energy of EH6(EC- ET(EH6) = 1.203 eV) turns out to be independent of the electric field. As a consequence, EH6is acceptor-like according to the missing Poole-Frenkel effect. Therefore, it can be excluded that the EH6-center and the prominent acceptor-like Z1/2-center belong to different charge states of the same microscopic defect as theoretically suggested. It is proposed that EH6is a complex containing a carbon vacancy and another component available at high concentrations. The activation energy of EH7(EC- ET(EH7) = 1.58 eV) has been evaluated indirectly by fitting the DLTS spectra of the EH6/7double peak taking the previously determined parameters of EH6into account.

Electronic Properties of ZnO/Si Heterojunction Prepared by ALD.

2011 ◽  
Vol 178-179 ◽  
pp. 130-135 ◽  
Author(s):  
Vincent Quemener ◽  
Mari Alnes ◽  
Lasse Vines ◽  
Ola Nilsen ◽  
Helmer Fjellvåg ◽  
...  
Keyword(s):  
Electronic Properties ◽  
Deep Level ◽  
Atomic Layer ◽  
Substantial Improvement ◽  
Conduction Band Edge ◽  
Energy Position ◽  
Layer Deposition ◽  
Current Voltage ◽  
Capacitance Voltage ◽  
Transient Spectroscopy

ZnO/n-Si and ZnO/p-Si heterostructures were prepared by Atomic layer deposition (ALD) and the electronic properties have been investigated by Current-Voltage (I-V), Capacitance-Voltage (C-V) and Deep level transient spectroscopy (DLTS) measurements. DLTS measurements show two dominants electron traps at the interface of the ZnO/n-Si junction with energy position at 0.07 eV and 0.15 eV below the conduction band edge, labelled E(0.07) and E(0.15), respectively, and no electrically active defects at the interface of the ZnO/p-Si junction. E(0.07) is reduced by annealing up to 400°C while E(0.15) is created at 500°C. The best heterostructure is found after heat treatment at 400°C with a substantial improvement of the current rectification for ZnO/n-Si and the formation of Ohmic contact on ZnO/p-Si. A reduction of the interface defects correlates with an improvement of the crystal structure of the ZnO film with a preferred orientation along the c-axis.

Sign in / Sign up

Export Citation Format

Share Document