Electrical data obtained from deep level transient spectroscopy investigations on deep defect centers in the 3C, 4H, and 6H SiC polytypes are reviewed Emphasis is put on intrinsic defect centers observed in as-grown material and subsequent to ion implantation or electron irradiation as well as on defect centers caused by doping with or implantation of transition metals (vanadium, titanium, chromium, and scandium)

Deep Defect Centers in Silicon Carbide Monitored with Deep Level Transient Spectroscopy

Results from current studies of the parameters of deep centers in 6H-, 4H-, and 3C-SiC are analyzed. Data are presented on the ionization energy and capture cross sections of centers formed by doping SiC with different types of impurities or during irradiation, as well as of intrinsic defects. The involvement of these centers in radiative and nonradiative recombination is examined. This analysis of published data illustrates the large effect of intrinsic defects in the SiC crystal lattice both on the formation of deep centers and on the properties of the epitaxial layers themselves, such as their doping level and polytype homogeneity.

Deep level centers in silicon carbide: A review

On behalf of the RD50 collaboration Abstract We present a review of the current status of research into new semiconductor materials for use as particle tracking detectors in very high radiation environments. This work is carried out within the framework of the CERN RD50 collaboration, which is investigating detector technologies suitable for operation at the proposed Super-LHC facility (SLHC). Tracking detectors operating at the SLHC in this environment will have to be capable of withstanding radiation levels arising from a luminosity of 10 35 cm -2 s -1 which will present severe challenges to current tracking detector technologies. The "new materials" activity within RD50 is investigating the performance of various semiconductor materials that potentially offer radiation hard alternatives to silicon devices. The main contenders in this study are silicon carbide, gallium nitride and amorphous silicon. In this paper we review the current status of these materials, in terms of material quality, commercial availability, charge transport properties, and radiation hardness studies. Whilst these materials currently show considerable promise for use as radiation hard tracking detectors, their ultimate success will depend on the continued improvement of the availability of high quality material.

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New materials for radiation hard semiconductor dectectors

This paper summarizes key findings in single-photon generation from deep level defects in silicon carbide (SiC) and highlights the significance of these individually addressable centers for emerging quantum applications. Single photon emission from various defect centers in both bulk and nanostructured SiC are discussed as well as their formation and possible integration into optical and electrical devices. The related measurement protocols, the building blocks of quantum communication and computation network architectures in solid state systems, are also summarized. This includes experimental methodologies developed for spin control of different paramagnetic defects, including the measurement of spin coherence times. Well established doping, and micro- and nanofabrication procedures for SiC may allow the quantum properties of paramagnetic defects to be electrically and mechanically controlled efficiently. The integration of single defects into SiC devices is crucial for applications in quantum technologies and we will review progress in this direction.

https://iopscience.iop.org/article/10.1088/1361-6633/aa5171/pdf

A review on single photon sources in silicon carbide.

A semi-insulating bulk single crystal of silicon carbide is disclosed that has a resistivity of at least 5000 Ω-cm at room temperature and a concentration of deep level trapping elements that is below the amounts that will affect the resistivity of the crystal, preferably below detectable levels. A method of forming the crystal is also disclosed, along with some resulting devices that take advantage of the microwave frequency capabilities of devices formed using substrates according to the invention.

Semi-insulating silicon carbide without vanadium domination

Trace impurities of vanadium in Lely‐grown silicon carbide single crystals have been detected by their strong, polytype‐specific photoluminescence in the 1.3–1.5 μm near‐infrared spectral range, as well as by infrared absorption. The spectra arise from the intra‐3d‐shell transitions 2E(3d1)→2T2(3d1) of V4+Si(3d1). Electron spin resonance reveals that VSi in SiC acts as a deep acceptor, V4+Si(3d1)/V3+Si(3d2)−A0/A−, and possibly also as a deep donor. The role of vanadium as minority‐carrier lifetime killer in SiC‐based optoelectronic devices is suggested from these data.

Infrared spectra and electron spin resonance of vanadium deep level impurities in silicon carbide

A detailed infrared‐spectroscopic study is presented of the intra 4f‐shell transitions 4I15/2→4I13/2 of Er3+(4f11), at λ=1.54 μm, in single‐crystal ErAs films deposited on GaAs substrates by molecular beam epitaxy. Using Fourier‐transform infrared absorption spectroscopy crystal‐field splittings of both the 4I15/2 ground state and the first electronically excited state 4I13/2 are observed. Good agreement is found between the measured transition energies and those calculated for 4f11 ions in a crystal field of cubic (Oh) symmetry, as expected for the Er lattice site in unstrained ErAs. From the infrared absorption data, the relevant cubic fourth and sixth‐order crystal field parameters are determined spectroscopically for the first time.

H. D. Müller

Papers

Infrared spectra and electron spin resonance of vanadium deep level impurities in silicon carbide

Crystal‐field splittings of Er3+(4f11) in molecular beam epitaxially grown ErAs/GaAs