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Fox News is one of the most popular news sources in the United States. Yet, there are those who reject the idea that Fox should be considered a news source in the first place, claiming it should be considered something more akin to propaganda. This article uses the ambiguity surrounding Fox News’ classification as an opportunity to explore how news sources get defined and categorized within journalism research and practice. It discusses three approaches that can be utilized to understand and categorize partisan media—producer-focused, audience-focused, and critical/normative. It explores the benefits and limitations of these perspectives and the need for scholarly inquiry that transverses and synthesizes them. We argue that an increasingly variegated news landscape calls for scholars to develop a richer vocabulary for distinguishing key features of partisan news outlets and greater reflexivity in research design that acknowledges the challenges inherent in translating meaning and values between producers, audiences, and scholars.

This essay reviews two new books examining different aspects of right-wing humor, “The Souls of White Jokes” (Stanford University Press, 2022) by Raúl Pérez and “That’s Not Funny” (University of California Press, 2022) by Matt Sienkiewicz and Nick Marx. It puts these works into conversation with a longer tendency within right-wing studies to focus on media content and motivations within a negative affective range. By focusing on the positive emotions associated with white supremacy and right-wing media, these books mark an important turning point away from reductionist accounts of the “reactionary mind” and toward a fuller understanding of the complex and contingent motivations of conservatives.

An analytical tool to design 4H-SiC power vertical Double-diffused Metal-Oxide-Semiconductor Field-Effect-Transistor is proposed. The model optimizes, in terms of the doping concentration in the Drift–region, the trade–off between the ON–resistance, RON, and the maximum blocking voltage, VBL, that is the Drain-Source voltage for which the avalanche breakdown appears at the p+–well/n-DRIFT junction together with the breakdown of the Gate oxide. Finding such trade-off means to maximize, Figure-Of-Merit. Our results are based on a novel full–analytical model of the electric field in the Gate oxide, EOX, whose generality is ensured by the absence of fitting and empirical parameters. Model results are successfully compared with 2D–simulations covering a wide range of device performances.

Point contact current voltage (PCIV) measurements were performed on 4H-SiC samples, both for n- an p-doped epitaxial layers as well as samples with rather shallow doping profiles realized by N- or Al-implantation in a range from 1016 cm-3 to 1019 cm-3. Surface preparation and measurement parameters were investigated in order to determine their influence on the measured resistance profiles. Furthermore depth profile measurements were performed on both an epitaxial layer as well as on implanted samples. These depth profiles could be measured reproducibly and showed good agreement with expected profiles for Al-implanted samples as well as for epitaxial layer whereas for N-implanted samples deviations between measured and expected profiles could be observed. It could be proven that PCIV profiling technique is a promising method for characterizing doped profiles in 4H-SiC, especially on Al-implanted samples.

In this study, the basic device features of a novel monolithically integrated solid-state-circuit-breaker (MI-SSCB) are demonstrated and analyzed using numerical simulations. Thereby, the MI-SSCB is built according to the concept of the dual thyristor. But, in comparison to similar technical solutions reported in literature, due to the advanced device structure proposed in this study a monolithically integration could be achieved for the first time.

In this work, the feasibility of the Bipolar-Injection Field Effect-Transistor (BIFET) [5] in two different Dual Thyristor type circuits [4] for an application as solid-state circuit breaker (SSCB) is experimentally verified. The Dual Thyristor type circuits are assembled from discrete silicon JFETs and a silicon carbide BIFET and are electrically characterized at various temperatures. The current-voltage characteristic shows the expected regenerative self-triggered turn-off capability under over-currents and the option to control the turn-off current by a passive resistor network. The issue with the adverse positive temperature coefficient of the trigger-current can be solved by putting the SiC BIFET in a cascode arrangement with a silicon Dual Thyristor. In this configuration the SiC BIFET provides the high voltage blocking capability and the silicon Dual Thyristor with its negative temperature coefficient controls the trigger-current. Transient analyses of both circuits indicate fast switching times of less than 50 μs seconds. It is demonstrated for the first time, that the SiC BIFET, due to its normally-on behaviour, used in a Dual Thyristor type circuit is a promising concept for self-triggered fuses in high current and high voltage applications.

In this article, we report the experimental results of a visible-light-blind 4H-polytype silicon carbide phototransistor able to detect ultraviolet (UV) radiations for wavelengths lower than 380 nm with a significative improvement in the optical gain compared with the state-of-the-art of 4H-SiC UV phototransistors. From the electro-optical measurements, the device shows a dark current of 0.62 pA, an ON-/OFF-current ratio of seven orders of magnitude up to bias voltage of −0.5 V, and an excellent optical gain of $1.14\cdot {10}^{{{5}}}$ at 300 nm, whereas it is only $2.6\cdot {10}^{-{{3}}}$ at 400 nm demonstrating a good rejection of visible radiations. Besides having high optical gain, the phototransistor is also more sensitive than the conventional 4H-SiC UV detectors for wavelengths with low penetration depths, because its structure is designed to have the electric field up to the radiated surface where the photogenerated electron–hole pairs are efficiently swept up before recombination occurs. The operating principle of the detector is also investigated, and we experimentally proved that differently from the conventional 4H-SiC bipolar junction transistor phototransistor, it is based on the change in the potential barrier height, which controls the current flow, due to the variation in the Fermi levels when the electron–hole pairs are photogenerated. A comparison with the state-of-the-art of 4H-SiC UV phototransistors is reported.

Metal-insulator-semiconductor capacitors used as a RC snubber attenuate voltage overshoots which may occur during switching phases. These devices feature good temperature stability up to 200°C and can be integrated very close to power switches on the same transfer substrate. As the capacitors need to withstand high voltages in most applications, thick dielectric layers have to be used, causing significant amount of wafer bow during processing. A dielectric stress compensation structure on the back side of the wafers is therefore introduced and shown to reduce the resulting wafer bow by up to 50%. Planar MIS capacitors using a 1 μm thick dielectric layer stack achieve dielectric breakdown voltages of up to 1000 V along with capacitance densities of 5.4 nF/cm2. In comparison, devices with a dielectric layer thickness of 250 nm exhibit a capacitance density of 13.6 nF/cm2 and a resulting dielectric breakdown voltage of 250 V.

Passive snubber networks are especially needed in fast switching power modules to prevent overvoltage from hard switching and to minimize electromagnetic interference [1]. In a half-bridge circuit as shown in Fig. 1 (a) dissipative RC snubber networks are beneficial over single pulse capacitors as they do not generate a resonant pole in the impedance spectrum, which can be seen in Fig. 1 (b). As only a small capacitance (e.g. 4 nF) is needed to reduce the overvoltage (Fig. 1 (c)), a monolithically integrated RC snubber can be realized on a silicon chip and packaged directly on the power module substrate. An improved module performance was already demonstrated for chip snubbers with 200 V operating voltage [2]. This work shows how the device design was enhanced for high manufacturability and reliable operations in a voltage range from 600 V to 900 V.

High-voltage 4H-SiC Junction Barrier Schottky diodes with a reverse breakdown voltage of over 4.5 kV and a turn-on voltage below 1 V have been fabricated. They achieved a forward current of 5 A at a forward voltage drop of 1.8 V and 20 A at 4.2 V. A low reverse leakage current of 0.3 μA at 1.2 kV and 37 μA at 3.3 kV was measured. The chip size was 7.3 mm x 7.3 mm, the active area 0.25 cm2 and the diode was able to handle a repetitive pulse current density of over 300 A/cm2 without degradation. Floating field rings in combination with a field-stop ring were used as edge termination to reach 73 % of the theoretical breakdown voltage. The epitaxial layer was 32 μm thick, with a nitrogen doping concentration of 1 x 1015 cm-3. The JBS diodes have been manufactured in a 100 mm SiC prototyping line, using well established processing technology, to achieve cost-efficient devices.