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Swift heavy ions, such as krypton ions, play a significant role in developing and enhancing the performance of various devices. In this study, the influence of Kr2+ on nitrogen-doped 4H-silicon carbide has been investigated using deep level transient spectroscopy (DLTS). Krypton ions, with an energy of 107 MeV, were used to irradiate the Au/Ni/4H-SiC Schottky barrier diodes (SBDs) at a fluence of 1 × 1010 cm–2 at room temperature (300 K). Before the irradiation of the samples, the electrical measurements revealed good rectifying behaviour. However, rectification properties of the Au/Ni/4H-SiC SBDs were completely lost after irradiation at a fluence of 1 × 1010 cm–2. Annealing was performed at 300 °C in flowing argon, and the current–voltage (I–V) and capacitance–voltage (C–V) revealed partial rectification. DLTS of the as-grown devices analyses revealed the presence of four deep level defects. After annealing the irradiated device, the DLTS spectra showed a reduction in the intensity of the E0.10 and the disappearance of the E0.12 as well as the E0.16 defects compared to that as-grown. Two defects with energies of 280 and 410 meV showed inverted peaks, as would have been expected from minority carriers trap instead of majority carriers, which led to confusion as the peaks were inverted. It was concluded that the peculiar characteristics of DLTS measurements on SBDs may be due to the extremely high value of the series resistance as well as the low capacitance. The results of this study provide insight into the behaviour of SBDs under extreme irradiation and can be used to improve the radiation tolerance of electronic devices made from SiC. [ABSTRACT FROM AUTHOR]

The impact of 1.8 MeV proton irradiation on metalorganic chemical vapor deposition grown (010) β -Ga2O3 Schottky diodes is presented. It is found that after a 10.8 × 10 13 cm − 2 proton fluence the Schottky barrier height of (1.40 ± 0.05 eV) and the ideality factor of (1.05 ± 0.05) are unaffected. Capacitance–voltage extracted net ionized doping curves indicate a carrier removal rate of 268 ± 10 cm − 1 . The defect states responsible for the observed carrier removal are studied through a combination of deep level transient and optical spectroscopies (DLTS/DLOS) as well as lighted capacitance–voltage (LCV) measurements. The dominating effect on the defect spectrum is due to the EC - 2.0 eV defect state observed in DLOS and LCV. This state accounts for ∼ 75 % of the total trap introduction rate and is the primary source of carrier removal from proton irradiation. Of the DLTS detected states, the EC - 0.72 eV state dominated but had a comparably smaller contribution to the trap introduction. These two traps have previously been correlated with acceptor-like gallium vacancy-related defects. Several other trap states at E C -0.36, E C -0.63, and E C -1.09 eV were newly detected after proton irradiation, and two pre-existing states at E C -1.2 and E C -4.4 eV showed a slight increase in concentration after irradiation, together accounting for the remainder of trap introduction. However, a pre-existing trap at EC - 0.40 eV was found to be insensitive to proton irradiation and, therefore, is likely of extrinsic origin. The comprehensive defect characterization of 1.8 MeV proton irradiation damage can aid the modeling and design for a range of radiation tolerant devices. [ABSTRACT FROM AUTHOR]

The need for simple-to-manufacture, solution-processable, tunable infrared active optoelectronic materials led to the development of infrared colloidal quantum dots, whose band gaps may be easily regulated by dimensional constraints resulting from the quantum confinement. Due to electronic deep-level trap states that limit effective mobility and function as effective recombination centers, nanocrystal (NC)-based optoelectronic devices still perform less well than what is predicted theoretically. The performance of NC-based optoelectronic devices can be considerably improved by identifying and passivating these defect levels. In this study, we use low-temperature I–V, C–V, C–F and the microcontroller-based deep level transient spectroscopy (DLTS) system to investigate the defect levels in the FTO/TiO2/HgTe/MoO3/Au device. The I–V measurements at low temperatures demonstrated the existence of exponential trap states, with an activation energy of 0.24 eV and a trap density of 3.18 × 10 17 cm − 3 . Low-temperature C–V and C–F measurements established the existence of deep trap states. With DLTS, we have located two deep trap levels (traps 1 and 2), with energies of 0.25 and 0.46 eV, capture cross-sections 9.7 × 10 − 23 and 4.35 × 10 − 14 cm 2 and a concentration of 2.4 × 10 17 cm − 3 , respectively. The surface states at the HgTe NCs and the oxygen vacancies at the TiO2 are the leading causes of the trap levels, which are primarily present at the interface of the TiO2/HgTe heterojunction. The transport mechanism in these heterojunction devices was happening mainly through these interface trap states. Passivating these defect levels is vital to increase the device effectiveness. [ABSTRACT FROM AUTHOR]

Presents a study that developed a novel linear prediction based parameter estimation algorithm for analyzing deep level transient spectroscopy (DLTS) signals. Linear prediction without a baseline constant; Details of the DLTS experiments conducted; Conclusion.

Provides information on a study which proposed a modified method of side data analysis of deep level transient spectroscopy spectra (DLTS). Use of DLTS; Theories employed in the study; Side data analysis for isolated constant voltage DLTS peaks.

Presents information on a study which described current-voltage, small-signal measurements and deep-level transient spectroscopy (DLTS) spectra of p-n junctions made by magnesium implantation into undoped indium phosphate. Reverse characteristics of all junctions; Experimental details; Description of the DLTS procedure; Admittance spectroscopy.

Presents information on a study which discussed the determination of the valence band offset between strained Si[sub1-x]Ge[subx] and unstrained silicon (Si) layers by deep level transient spectroscopy (DLTS) on Si/Si[sub1-x]Ge[subx]/Si quantum well structures. Steps of the DLTS measurements; Experimental details; Leakage problems.

Presents information on a general two-dimensional method for processing deep level transient spectroscopy data. Application of the numerical solving of the inverse ill-posed problem of the theoretical model via regularization algorithms; Formula for the capacitance transient for a single deep level in the case of box-car measurement technique; Recurrent dependence of the iterative method.

Discusses a study which investigated deep level distributions in B-doped Si/Si[sub1-x]Ge[subx]/Si layers grown by molecular beam epitaxy using deep level transient spectroscopy. Terms in which broadening in the deep level spectra is discussed; Consequence of the significant band bending; Advantage of the introduction of a heterojunction.

Provides a quantitative understanding of the merits and disadvantages of various methods of analyzing the deep level transient spectroscopy transients and spectrum for semiconductor characterization. Derivation of the covariance method of linear predictive modeling; Approach used to compare the different transient analysis techniques; Conclusions.

Introduces an accurate figure of merit that assesses the ability of a deep level transient spectroscopy (DLTS) analysis method's ability to resolve defects in semiconductors. Description of the resolution figure of merit; Determination of the resolution figure of merit for various analysis methods; Application of the resolution figure of merit in predetermining the success/failure of DLTS analyses' ability to resolve the defects.

Presents a study which proposed a method to determine the accurate values of deep level parameters in Schottky diodes. Implication of the numerical modeling of deep level transient spectroscopy (DLTS) signals; Theoretical analysis of the conventional DLTS model; Description of the DLTS signal with leakage current effect.

Presents an investigation of defects in n-type germanium at room temperature using deep level transient spectroscopy. Experiment conducted; Discussion; Conclusion.

Proposes a method for non-exponential deep level transient spectroscopy (DLTS) theoretical analysis. Basis for the method; Possibility of obtaining the shape of the deep level energy spectrum from the noiscy DLTS spectra in systems; Regularization methods for solving the inverse problem for the theoretical DLTS model.

Presents a study which determine the insulator/semiconductor interface trap density by correlation deep level transient spectroscopy method. Analysis and derivation of the method; Results; Conclusion.

Proposes a model for the characterization of volume traps in enhancement-mode field-effect transistors (FET) by current deep level transient spectroscopy. Overview of previously developed models of volume traps in enhancement-mode (FET); Development of the proposed model; Characterization of a deep trap in a bulk enhancement-mode.

Presenst a study which introduced a theoretical treatment of deep level transient spectroscopy under minority-carrier injection conditions. Method of the study; Results and discussion; Conclusion.

Presents a study which used the capacitance-voltage technique and deep-level transient spectroscopy to examine the silicon-silicon epitaxial layer structures grown by the limited reaction process using silane diluted in hydrogen. Physical parameters of the structure; Density and capture cross section of the states; Doping level and thickness of the layers.

Presents a study that reported on a deep level transient spectroscopy study of proton irradiation induced defects in n[sup+]p indium phosphide mesa diodes. Description of the devices used in the study; Expression for calculating an estimate of the defect concentration; Measured annealing rates of proton irradiation induced defects.

Presents a study that detailed deep-level transient spectroscopy (DLTS) measurements made to obtain the activation energy and capture cross section in Schottky diodes. Functions derived for metal-semiconductor junctions; Parameter important in the study of metal-semiconductor junctions; Compound semiconductors in which DLTS data are useful.

Presents a study that proposed a method to analyze digitally recorded capacitive transients for deep level spectroscopy of semiconductors. Methodology; Background on deep-level transient spectroscopy; Application of the proposed method in aluminum-gallium arsenide semiconductors.

Presents a study that examined deep level transient spectroscopy measurements of electron traps in irradiated n-type silicon. Analysis of the depth concentration profiles of the samples; Examination of the dose dependence of the defects; Methodology.

Presents a study that extended the theory of the deep level transient spectroscopy (DLTS) measurement to the more general case in which both the doping profile and the trap profile vary with depth. Method of calculating exact DLTS transients for the general case; Factors which determine the degree to which the DLTS transient can be approximated by an exponential; Analysis of the DLTS measurement technique for depth-dependent dopant and trap concentration profiles.

Provides information on a study which suggested the use of a new deep level transient spectroscopy (DLTS) technique, which allows the deep level parameters to be obtained from a single temperature scan. Application of the DLTS technique; Function of the technique; Problems with the standard DLTS technique.

Examines the effect of accelerated lifetime stress tests on AlGaAs/GaAs high electron mobility transistor (HEMT) structures. Techniques of deep-level transient spectroscopy (DLTS) for obtaining trap information; Diagram of the equipment used to measure capacitance DLTS; Comparison of capacitance DLTS with current DLTS for an unstressed HEMT.

Describes the utility of isothermal current deep level transient spectroscopy (DLTS) techniques in directly probing solar cells. Modifications made to the standard DLTS technique; Reason for choosing to make the DLTS measurements at constant temperature; Determination of the deep level thermal activation energy and carrier capture cross section.

Deals with a study focused on a deep-level transient spectroscopy of deep donor traps existing in n-type gallium arsenide epitaxial layers grown by close-spaced vapor transport. Traps seen in other samples in addition to ELCS1; Information on the close-spaced vapor transport technique; Step taken in order to determine deep donor traps.

Focuses on a study which investigated EL2 midgap trap in gallium arsenide using deep-level transient spectroscopy (DLTS) for contacts having a large range of Schottky barrier height. Calculation of the quasi-Fermi level in the depiction region; Effect of Schottky barrier height on the deep trap signal; Observation on signal intensity in the DLTS.

Presents a study which described a barrier modulation deep-level transient spectroscopy (BMDLTS) technique for the direct characterization of deep centers in an insulator slab sandwiched between doped semiconductor layers. Mechanisms of current transport in semiconductor-insulator-semiconductor structures; Principles of the BMDLTS technique; Numerical simulations and results.

Focuses on a study that examined the deep level transient spectroscopy (DLTS) technique that suggests a method for analyzing data for DLTS signal intensity. Information on the DLTS; Use of predetermined times; Resolution of practical DLTS approaches.

Presents a method of analyzing the deep level transient spectroscopy (DLTS) transient signal by recording its in-phase (I) and quadrature (Q) DLTS spectra using a two-phase lock-in amplifier with a wave mixing function. Discussion of DLTS; Illustration of the IQ-DLTS technique; Validity of assuming a purely exponential DLTS transient.

Presents a study that analyzed the method of determining trap capture cross sections by deep level transient spectroscopy (DLTS) of semiconductors. Background on the Schottky barrier; Examination of the DLTS techniques used for capture cross-section determination; Investigation of improved capture cross-section modeling.

Studies the optimization of the energy resolution of deep level transient spectroscopy (DLTS). Effects of crystal defects in semiconductors; Goal of DLTS signal processing; Discussion on the rate window technique.

Presents a method for determining minority carrier generation lifetimes and hold times in metal-oxide semiconductor (MOS) devices. Application of deep level transient spectroscopy to MOS relaxation transients; Results of the study; Conclusions.

Presents a study which examined the use of Schottky barrier diodes (SBD) to detect minority-carrier defects by deep level transient spectroscopy (DLTS). Background on the minority-carrier injections in SBD; Consideration for the selection of SBD for a DLTS analysis of minority-carrier defects.

Describes the method of deep level transient spectroscopy in the profiling of p-n junctions, Schottky barriers or metal-oxide-semiconductor capacitors. Discussion on the measurement of a defect concentration; Theoretical aspects of defect profiling; Validation of the theoretical filing factor correction.

Presents a study which conducted a deep level transient spectroscopy analysis of electron hole traps in bulk-grown gallium arsenide. Experimental procedure; Results; Discussion.

Presents a study which examined the anomalous majority-carrier peaks in deep level transient spectroscopy spectra for gallium arsenide. Experimental results; Theoretical considerations; Discussion.

Examines the optimization and preservation of deep-level transient spectroscopy (DLTS) signal response. Basis of the DLTS experiment; Details on the classical DLTS experiment; Discussion of findings.

Presents a study that investigated deep levels in lead iodate (PbI[sub2]) by photoinduced current transient spectroscopy for the first time. Benefits from the four-gate treatment method; Features of the excited state of the crystal; Use of PbI[sub2]; Factors that evidenced several energy levels.

Despite a high lateral breakdown voltage above 10 kV for large contact distances and a breakdown field of 5 MV cm−1 for short contact distances, an Al0.9Ga0.1N/GaN heterostructure with an 8 nm strained GaN channel grown on an AlN/sapphire template suffers from a low and anisotropic mobility. This work deals with a material study to elucidate this issue. Threading dislocations were observed along the growth direction in transmission electron microscopy pictures and are more in number in the (11−20) plane. Steps were also detected in this plane at the GaN channel interfaces. With the help of device simulations and static characterizations, the deep level transient spectroscopy technique allowed five traps located in the GaN channel to be identified. Most of them are associated with nitrogen- or gallium-vacancy-related defects and are expected to be localized at the interfaces of GaN with the buffer and the barrier. It is likely that these electrically active defects contribute to reduce the mobility in the two-dimensional electron gas. In addition, a link was established between the mobility and the dependence of the quality of the channel interfaces on the crystallographic orientation. [ABSTRACT FROM AUTHOR]

High-voltage gradual p0–i–n0 junctions of AlxGa1 –xAs1 –ySby with x ~ 0.24 and y ~ 0.05 in the i‑region were studied using capacitance-voltage characteristics method and transient spectroscopy of deep levels. It has been established that the effective recombination trap in them is the DX-center of the Si donor impurity, with a thermal activation energy Et = 414 meV, a capture cross section σn = 1.04 × 10–14 cm2, and a concentration Nd = 2.4 × 1015 cm–3. In the heterostructures studied, there were no deep levels associated with dislocations. [ABSTRACT FROM AUTHOR]

The presence of deep levels in a silicon-oxygen (Si-O) superlattice (SL) deposited on p-type silicon substrates has been investigated by deep-level transient spectroscopy (DLTS) on thermally evaporated Cr Schottky barriers (SBs). The SLs have been fabricated with different thicknesses of the silicon interlayers, formed by chemical vapor deposition. It is shown that a broad band of hole traps is present near the surface of the SB, which is associated with the SL. In addition, the activation energy corresponding with the peak maximum shifts to higher values with respect to the valence band and gives rise to a higher trap concentration with increasing silicon interlayer thickness. It is proposed that these states are associated with the structural defects found in similar SL structures, that is, with the epitaxial quality and not with the SiO bonds in the atomic layers. The change in the DLT-spectra with silicon thickness could be related with the transformation of the structural defects from small self-interstitial clusters to stacking faults. [ABSTRACT FROM AUTHOR]