Deep Levels in n-Type 4H-Silicon Carbide Epitaxial Layers Investigated by Deep-Level Transient Spectroscopy and Isochronal Annealing Studies

Nguyen, Khai V.; Pak, Rahmi O.; Oner, Cihan; Mandal, Krishna C.

doi:10.1109/tns.2016.2535212

Cited by 25 publications

(7 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the sake of simplicity, the defect levels with activation energy above room temperature are shown in the figure. As is evident from the DLTS spectra, all the deep level defects were very much stable up to an annealing temperature of 800 • C. The lesser apparent defects as have been observed previously [82] are also summarized as follows. The capture cross-sections of the trap centers Ti(c), Z 1/2 , and EH 5 were reduced by an order of magnitude when the samples were annealed at a temperature of 400 • C. The respective defect densities were observed to follow a similar trend throughout the isochronal annealing studies.…”

Section: Isochronal Annealing Studiessupporting

confidence: 73%

“…As is evident from the DLTS spectra, all the deep level defects were very much stable up to an annealing temperature of 800 °C. The lesser apparent defects as have been observed previously [82] are also summarized as follows. The capture crosssections of the trap centers Ti(c), Z1/2, and EH5 were reduced by an order of magnitude when the samples were annealed at a temperature of 400 °C.…”

Section: Isochronal Annealing Studiesmentioning

confidence: 55%

“…To study the defect dynamics, i.e., transformation or disappearance of defects because of atomic motion under the influence of temperature, isochronal annealing experiments were carried out on 50 µm n-type Ni/4H-SiC (n-S50) SBDs [82]. As mentioned earlier in Section 2, the samples were annealed at a particular temperature for 30 min followed by DLTS measurements.…”

Section: Isochronal Annealing Studiesmentioning

confidence: 99%

See 2 more Smart Citations

Advances in High-Resolution Radiation Detection Using 4H-SiC Epitaxial Layer Devices

2020

Self Cite

View full text Add to dashboard Cite

Advances towards achieving the goal of miniature 4H-SiC based radiation detectors for harsh environment application have been studied extensively and reviewed in this article. The miniaturized devices were developed at the University of South Carolina (UofSC) on 8 × 8 mm 4H-SiC epitaxial layer wafers with an active area of ≈11 mm2. The thicknesses of the actual epitaxial layers were either 20 or 50 µm. The article reviews the investigation of defect levels in 4H-SiC epilayers and radiation detection properties of Schottky barrier devices (SBDs) fabricated in our laboratories at UofSC. Our studies led to the development of miniature SBDs with superior quality radiation detectors with highest reported energy resolution for alpha particles. The primary findings of this article shed light on defect identification in 4H-SiC epilayers and their correlation with the radiation detection properties.

show abstract

Section: Isochronal Annealing Studiessupporting

confidence: 73%

Section: Isochronal Annealing Studiesmentioning

confidence: 55%

Section: Isochronal Annealing Studiesmentioning

confidence: 99%

See 1 more Smart Citation

Advances in High-Resolution Radiation Detection Using 4H-SiC Epitaxial Layer Devices

2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…[30,31] This trap is widely designated as Z 1/2 , an intrinsic growth defect in SiC and most likely related to carbon vacancies. [32] For E2 peak, the defect level is situated at E C -0.16 eV, which is attributed to the ionized titanium acceptor residing at cubic Si lattice sites. [33][34][35] Zhang et al [36] and Dalibor et al [37] have also identified the similar defect level E C -0.16 eV for a Ti electron trap level in as-grown SiC epilayers.…”

Section: Resultsmentioning

confidence: 98%

Influence of deep defects on electrical properties of Ni/4H-SiC Schottky diode

Li²,

et al. 2019

Chinese Phys. B

View full text Add to dashboard Cite

In this paper, we investigate the influence of deep level defects on the electrical properties of Ni/4H-SiC Schottky diodes by analyzing device current-voltage (I-V ) characteristics and deep-level transient spectra (DLTS). Two Schottky barrier heights (SBHs) with different temperature dependences are found in Ni/4H-SiC Schottky diode above room temperature. DLTS measurements further reveal that two kinds of defects Z 1/2 and Ti(c) a are located near the interface between Ni and SiC with the energy levels of E C -0.67 eV and E C -0.16 eV respectively. The latter one as the ionized titanium acceptor residing at cubic Si lattice site is thought to be responsible for the low SBH in the localized region of the diode, and therefore inducing the high reverse leakage current of the diode. The experimental results indicate that the Ti(c) a defect has a strong influence on the electrical and thermal properties of the 4H-SiC Schottky diode.

show abstract

“…Figure 7 shows the Arrhenius plots of the leakage current as a function of 1000/T at four different reverse voltages, i.e., 50 V, 100 V, 150 V, and 200 V. The activation energy is given by the slope of linear fit of data. Values from 0.57 eV to 0.65 eV were calculated in the voltage range 50 V to 200 V. According to the literature, these values refer to major deep levels (Z 1/2 center) within the bandgap [26][27][28]. Figure 7 shows the Arrhenius plots of the leakage current as a function of 1000/T at four different reverse voltages, i.e., 50 V, 100 V, 150 V, and 200 V. The activation energy is given by the slope of linear fit of data.…”

Section: Temperature Dependencementioning

confidence: 99%

Silicon Carbide Microstrip Radiation Detectors

Puglisi

Bertuccio

2019

Micromachines

View full text Add to dashboard Cite

Compared with the most commonly used silicon and germanium, which need to work at cryogenic or low temperatures to decrease their noise levels, wide-bandgap compound semiconductors such as silicon carbide allow the operation of radiation detectors at room temperature, with high performance, and without the use of any bulky and expensive cooling equipment. In this work, we investigated the electrical and spectroscopic performance of an innovative position-sensitive semiconductor radiation detector in epitaxial 4H-SiC. The full depletion of the epitaxial layer (124 µm, 5.2 × 10 13 cm −3 ) was reached by biasing the detector up to 600 V. For comparison, two different microstrip detectors were fully characterized from −20 • C to +107 • C. The obtained results show that our prototype detector is suitable for high resolution X-ray spectroscopy with imaging capability in a wide range of operating temperatures. very low noise levels, even at the high electric fields applied during their operation. Moreover, the high thermal conductivity of 4H-SiC (3.8 W/cm • C) enables SiC devices to dissipate large amounts of excess generated heat, which would cause a temperature increase, responsible for degradation of the device's performance. High thermal conductivity is useful for increasing the radiation hardness of the detector, as well as for controlling the operating temperature when the front-end electronics are close to, or in contact with, the detector [16]. Furthermore, SiC can withstand an internal electric field over eight to ten times greater than GaAs or Si (2 MV/cm for 4H-SiC vs. 0.4 MV/cm for GaAs or 0.3 MV/cm for Si) without undergoing avalanche breakdown. This property enables the fabrication of very high-voltage devices [17]. In the case of X-ray detection and spectroscopy, the high breakdown field of 4H-SiC allows, in principle, the detector to work always in the regime of saturated-electron and hole-drift velocities, independently of the detector's active region width. When this operation condition is coupled with epitaxial material of high crystalline quality, a full and fast charge collection can be expected [16], as well as a high sensitivity, as already demonstrated [18]. Such properties allow SiC-based devices to be operated without any costly, bulky, and power-consuming cooling systems, as in the case of Si-or Ge-based devices, while maintaining an excellent signal-to-noise ratio over a wide range of temperatures. This leads to notable advantages in terms of the lower cost, more compact size, lighter weight, lower power consumption, and higher performance of SiC detectors. Further explanation of the electrical properties of SiC in connection with the ionizing detector performance benefits can be found in [16].Microstrip detectors find application where the position of the radiation interaction is necessary information for the physical process to be studied. The advantage of using microstrips with respect to other position-sensitive detectors, such as pixel detectors, is a lower number of readout channels. Se...

show abstract

Deep Levels in n-Type 4H-Silicon Carbide Epitaxial Layers Investigated by Deep-Level Transient Spectroscopy and Isochronal Annealing Studies

Cited by 25 publications

References 53 publications

Advances in High-Resolution Radiation Detection Using 4H-SiC Epitaxial Layer Devices

Advances in High-Resolution Radiation Detection Using 4H-SiC Epitaxial Layer Devices

Influence of deep defects on electrical properties of Ni/4H-SiC Schottky diode

Silicon Carbide Microstrip Radiation Detectors

Contact Info

Product

Resources

About