Increasing Rf Power Research Articles

Impact of Ar plasma bombardment on the composition and surface roughness of GaAs wafer

The surface property of GaAs has an important impact on device performance, so how to improve the surface quality in reactive ion etching process is one of the key issues. In this paper, the composition and roughness changes of GaAs surface subjected to Ar plasma bombardment were investigated. It was found that the relative contents of Ga2O3 and As2O3 of the surface decreased with the increase of RF power, and the distribution depths of the compositions were different. In addition, dielectric constant increased with the increase of RF power. It was found that the surface roughness can be reduced after the plasma bombardment. Furthermore, the surface roughness and Ga/As component ratio followed a certain trend with the RF power. When the RF power was lower than 150 W, the surface roughness and Ga/As component ratio had the same trend, and when the RF power was higher than 150 W, they had the opposite trend. These results are helpful for the improvement of GaAs-based wafer-bonding strength and the performance of optoelectronic structures.

Nonlinear response of very high frequency contour mode resonators

We explore the source of nonlinearities in Aluminum Nitride (AlN) Contour Mode Resonators (CMRs) operating in the Very High Frequency (VHF) range. We demonstrate that the red-shift of the resonance frequency found in VHF CMRs when the input RF power increases is due to nonlinear stiffness appearing from self-heating, and variable damping due to geometric nonlinearities. Moreover, we find a linear relationship between the variable damping coefficient and the resonator quality factor (Q). Such nonlinear mechanisms are modeled using a spring-mass-damper physical system and, in the electrical domain, a modified Butterworth-Van Dyke (MBVD) circuit where the nonlinear stiffness and variable damping are captured by a charge-dependent motional capacitor and a charge-dependent motional resistor, respectively. Detailed guidelines are provided to accurately analyze nonlinear CMRs using full-wave numerical simulations based on a finite-element method. Such simulations allow us to isolate the influence of each independent nonlinear mechanism and establish a relation between variable damping and geometric nonlinearities. Circuit and full-wave numerical simulations are in good agreement with measured data from fabricated 225 MHz CMRs exhibiting different Q. Finally, we exploit nonlinearities in high-Q CMRs to generate frequency combs at the MHz range opening the door to new exciting applications in telecommunication and sensing.

The effects of graphene intrinsic defects on the formation of extrinsic defects by plasma treatment

Two-dimensional materials, like graphene, are expected to make highly efficient permeation membranes for separation and sensing applications; however, defects of a specific size and location must be added to the film to make them selectively permeable. Though techniques like TEM drilling give precise information on size and location, this method is not scalable for eventual commercial use. Plasma treatments are a scalable alternative, but there is less information on where the defect formation begins and how intrinsic defects affect pore formation. This work seeks to understand these effects by using Raman spectroscopy at the same location before and after plasma treatments to map how the intrinsic defects affect the formation of extrinsic defects to create nanopores. Defect density increases with increasing RF power, independent of the gas used during the plasma treatment, suggesting that the mechanism is due to ion bombardment. Coalesced and arrested graphene syntheses are used to study the relative trends of defect formation and map existing graphene grain boundary locations. The results show that regions starting with high densities of intrinsic defects, potentially due to strain, were found to degrade into nanocrystalline graphene first on the amorphization trajectory, even before grain boundaries.

Effects of power on ion behaviors in radio-frequency magnetron sputtering of indium tin oxide (ITO)

This study delves into ion behavior at the substrate position within RF magnetron discharges utilizing an indium tin oxide (ITO) target. The positive ion energies exhibit an upward trajectory with increasing RF power, attributed to heightened plasma potential and initial emergent energy. Simultaneously, the positive ion flux escalates owing to amplified sputtering rates and electron density. Conversely, negative ions exhibit broad ion energy distribution functions (IEDFs) characterized by multiple peaks. These patterns are clarified by a combination of radiofrequency oscillation of cathode voltage and plasma potential, alongside ion transport time. This elucidation finds validation in a one-dimensional model encompassing the initial ion energy. At higher RF power, negative ions surpassing 100 eV escalate in both flux and energy, posing a potential risk of sputtering damages to ITO layers.

Enhanced Photoelectrochemical Activity Realized from WS2 Thin Films Prepared by RF‐Magnetron Sputtering for Water Splitting

AbstractWe report the synthesis of tungsten sulfide (WS2) films using RF‐magnetron sputtering at different RF powers. X‐ray diffraction (XRD) data confirm the hexagonal crystal structure of WS2 with an average crystallite size of ∼44.54 Å. With increased RF power, the preferred orientation of WS2 crystallites shifts from (002) to (100). Linear sweep voltammetry (LSV) was used to assess the Photoelectrochemical (PEC) activity of WS2 films. The film deposited at 150 W demonstrated the highest photocurrent density of 5.44 mA/cm2. The 150 W film also showed a lower Tafel slope of ∼0.374 V/decade, indicating superior PEC activity. Mott Schottky's (MS) analysis revealed a notable shift in the flat band potential towards the negative side, suggesting a shifting of the Fermi level towards the conduction band. WS2 film grown at 150 W demonstrated a majority charge carrier density of 6.2×1021 cm−3 and a depletion layer width of 1.54 nm. The observed low charge transfer resistance of 155 Ω contributed to the enhanced PEC activity with a relaxation time constant of 37 ms. These properties suggest that WS2 can be suitable for PEC water splitting.

Effects of Optical Sampling Pulse Power, RF Power, and Electronic Back-End Bandwidth on the Performance of Photonic Analog-to-Digital Converter.

The effects of optical sampling pulse power, RF power, and electronic back-end bandwidth on the performance of time- and wavelength-interleaved photonic analog-to-digital converter (PADC) with eight-channel 41.6 GHz pulses have been experimentally investigated in detail. The effective number of bits (ENOB) and peak-to-peak voltage (Vpp) of converted 10.6 GHz electrical signals were used to characterize the effects. For the 1550.116 nm channel with 5.2 G samples per second, an average pulse power of 0 to -10 dBm input to the photoelectric detector (PD) has been tested. The Vpp increased with increasing pulse power. And the ENOB for pulse power -9~-3 dBm was almost the same and all were greater than four. Meanwhile, the ENOB decreased either when the pulse power was more than -2 dBm due to the saturation of PD or when the pulse power was less than -10 dBm due to the non-ignorable noise relative to the converted weak signal. In addition, RF powers of -10~15 dBm were loaded into the Mach-Zehnder modulator (MZM). The Vpp increased with the increase in RF power, and the ENOB also showed an increasing trend. However, higher RF power can saturate the PD and induce greater nonlinearity in MZM, leading to a decrease in ENOB, while lower RF power will convert weak electrical signals with more noise, also resulting in lower ENOB. In addition, the back-end bandwidths of 0.2~8 GHz were studied in the experiments. The Vpp decreased as the back-end bandwidth decreased from 8 to 3 GHz, and remained nearly constant for the bandwidth between the Nyquist bandwidth and the subsampled RF signal frequency. The ENOB was almost the same and all greater than four for a bandwidth from 3 to 8 GHz, and gradually increased up to 6.5 as the back-end bandwidth decreased from the Nyquist bandwidth to 0.25 GHz. A bandwidth slightly larger than the Nyquist bandwidth was recommended for low costs and without compromising performance. In our experiment, the -3 to -5 dBm average pulse power, about 10 dBm RF power, and 3 GHz back-end bandwidth were recommended to accomplish both a high ENOB more than four and large Vpp. Our research provides a solution for selecting optical sampling pulse power, RF power, and electronic back-end bandwidth to achieve low-cost and high-performance PADC.

Research On Etching of Distributed Bragg Reflector

This study investigated the effect of etching process parameters on the sidewall morphology and bottom metal etching damage of Distributed Bragg Reflector (DBR), and analyzed the underlying mechanisms. By comparing the etching morphology under different RF power and pressure conditions, it was found that increasing RF power and reducing pressure can solve the problem of sidewall fracture and obtain a smooth sidewall morphology. By comparing the effect of different process gases on the sidewall angle, it was found that adding O2 can reduce the DBR/Photoresit selectivity and sidewall angle while adding BCl3 can increase the DBR/Photoresit selectivity and sidewall angle. Therefore, the sidewall angle can be adjusted by controlling the type and flow rate of the etching gas. By comparing the DBR/metal selectivity under different RF power, it was found that as the RF power decreases, the DBR/metal selectivity increases, which can prevent metal splashing caused by over-etching of metal. Therefore, in DBR etching, high RF power is used for main etching to obtain a smooth sidewall morphology and the sidewall angle can be adjusted by varying the gas type and flow rate, while low RF power is used for over-etching to improve the DBR/metal selectivity and prevent metal over-etching. This study has reference significance for the development of the inverted chip DBR process.

The evolution of preferred orientation and morphology of AlN films under various sputtering parameters

Wurtzite aluminum nitride (AlN) films with (100) and (002) preferred orientations are obtained on Si (100) wafers by radio frequency magnetron sputtering. The effects of target to substrate distance (TSD), RF power, deposition pressure and substrate temperature on crystal orientation and morphology of AlN films are analyzed. It is demonstrated that the TSD is the key factor affecting the preferred orientation of AlN films. The preferred orientation transforms from (002) to (100) with the increase of TSD. Further increase of substrate temperature and RF power causes the coexistence of (002) and (100) orientation. The evolution of orientation is explained by the change in kinetic energy of sputtered particles. The correlation between the crystal orientation and the surface morphology is investigated.

Contribution of electron density to plasma decomposition rate of methane

Hydrogen extraction from methane will be a common and useful technique in hydrogen production systems and fuel cycle systems of deuterium-tritium fusion reactors. Since tritium is a precious fuel, it needs to be extracted from impurity gases such as tritiated methane contained in the exhaust gas from the plasma vessel of a fusion reactor. An experimental work was conducted in this study to investigate the electron collision of methane decomposition reaction in helium plasma. A special attention was placed on the electron density distribution in a plasma chamber, and the dependence of the decomposition rate on the methane/helium ratio. The experimental results showed that methane decomposition rate and electron density tended to increase linearly with increasing RF power. This suggests that a strong dependence of electron collision on methane decomposition. Eventually, the dependence of methane decomposition rate on electron density, total pressure, and inlet methane concentration in a gas flow-type helium plasma reactor was successfully formulated. This study provides new sight for demonstrating the contribution of electron density in RF plasma assisted methane decomposition, and the summarized equation offers potential for reactor design on promising energy utilization.

Design of 6 GHz Variable-Gain Low-Noise Amplifier Using Adaptive Bias Circuit for Radar Receiver Front End

This paper presents a variable-gain low-noise amplifier (VGLNA) based on an adaptive bias (ADB) circuit for the radar receiver front end. The ADB circuit processes the signal separated by a coupler at the LNA output port. First, the ADB circuit rectifies the coupled signal into positive DC voltage through a rectifier, which is then inverted to control a junction-gate field-effect transistor (JFET). The voltage-controlled current of JFET flows through a voltage-divider network and finally produces the DC biasing voltage for the BJT base termination, which decreases with the increase in the input RF power. The proposed VGLNA operates automatically in high gain at low input power and low gain at high input power, providing a wider dynamic range as compared to the constant-bias counterpart. For validation, a prototype is fabricated and measured at 6 GHz. As observed, the base biasing voltage generated by the ADB circuit is changed from 858 mV to 798 mV as the input power increases from −50 dBm to 0 dBm. As a result, the dynamic range represented by the input P1dB point (IP1dB) has an increase of 6.5 dB, while LNA still maintains a high gain of 15.15 dB at low input power.

The deposition of Ir/YSZ double-layer thin films on silicon by PLD and magnetron sputtering: Growth kinetics and the effects of oxygen

This work focuses on the epitaxial growth process and kinetics of silicon-based Ir/yttria-stabilized zirconia (YSZ) bilayer films prepared by PLD and magnetron sputtering, including the sequential growth of a YSZ film, an Ir seed layer, and an Ir film on a silicon substrate. The results show that for growing YSZ films by PLD at the target-to-substrate distance of 60 mm, the higher the laser energy density and the oxygen pressure, the lower the laser frequency, the higher the epitaxy quality. In addition, for the preparation of the Ir-seed layer by PLD, background gas decelerates the plasma and suppresses self-sputtering and implantation, which is beneficial to obtaining a high-quality seed layer. In particular, introducing a small amount of oxygen is able to improve the epitaxial quality of the films during the growth of Ir-seed and Ir films, and the mechanism of oxygen is proposed. For the growth of Ir films by magnetron sputtering, the growth rate and the energy of argon ions increased with the increase of RF power, while the epitaxial quality is the opposite. The kinetic theory and simulation results demonstrate that this trend is mainly caused by the increase in the number of particles reaching the substrate without significantly increasing the distribution of high-energy particles. Finally, high-quality Ir (100) films on the YSZ (100) with a fresh surface are prepared. It is shown that increasing the epitaxy quality of the YSZ (100) film and the growth temperature of the Ir film can improve the quality of Ir film. Based on our results, the growth of Ir films on YSZ films with fresh surfaces resulting from in-situ argon plasma cleaning provides a new idea for preparing Ir (100)/YSZ (100) bilayer epitaxial film.

Highly Integrated Wideband Transmit/Receive Module for X-Band SAR Applications

The roadmaps of satellite-based synthetic aperture radar (SAR) systems show a trend that requires a continuous improvement of the active antenna in terms of operating bandwidth, scanning angle capability, and swath width, thus leading to the demand for increased RF power and better power efficiency of the RF transmitter. Moreover, compact size and light weight are relevant objectives for making the overall SAR instrument appealing for future applications. The transmit/receive module (TRM) shown in this paper was developed while combining all these requirements in a cost-effective approach. A careful design of all relevant RF interconnects and passive devices was performed to ensure the largest output power from the last high-power amplifier of the transmitting chain, the lowest noise figure at the input of the receiving chain, and the calibration capability for appropriately tuning the TX and RX signal. The TRM was manufactured and experimentally tested to verify its performances. The measurement results show the superior performances of the proposed compact high-power large-bandwidth TRM. The achieved target objectives make the design of the proposed TRM readily applicable for the development of a compact, high-power, and highly integrated AESAs to be used for next-generation satellite constellations for Earth observation.

Comparison of heating mechanisms of argon helicon plasma in different wave modes with and without blue core

In this work, we investigated the discharge characteristics and heating mechanisms of argon helicon plasma in different wave coupled modes with and without blue core. Spatially resolved spectroscopy and emission intensity of argon atom and ion lines were measured via local optical emission spectroscopy, and electron density was measured experimentally by an RF-compensated Langmuir probe. The relation between the emission intensity and the electron density was obtained and the wavenumbers of helicon and ‘Trivelpiece-Gould’ (TG) waves were calculated by solving the dispersion relation in wave modes. The results show that at least two distinct wave coupled modes appear in argon helicon plasma at increasing RF power, i.e. blue core (or BC) mode with a significant bright core of blue lights and a normal wave (NW) mode without blue core. The emission intensity of atom line 750.5 nm (I ArI750.5nm) is related to the electron density and tends to be saturated in wave coupled modes due to the neutral depletion, while the intensity of ion line 480.6 nm (I ArII480.6nm) is a function of the electron density and temperature, and increases dramatically as the RF power is increased. Theoretical analysis shows that TG waves are strongly damped at the plasma edge in NW and/or BC modes, while helicon waves are the dominant mechanism of power deposition or central heating of electrons in both modes. The formation of BC column mainly depends on the enhanced central electron heating by helicon waves rather than TG waves since the excitation of TG waves would be suppressed in this special anti-resonance region.

Energy Efficiency Enhancement of Inductively Coupled Plasma Torch: Computational Study.

In this research, we studied the performance analysis of inductively coupled radiofrequency plasma “RF-ICP” torch used in multi-material processing. A 2D numerical model built with COMSOL Multiphysics was used to study the discharge behavior and evaluate the overall efficiency transmitted into the plasma system. The temperature and velocity flow of the plasma were investigated. The numerical results are consistent with previous experimental studies. The temperature and velocity profiles are represented under a wide range of RF power and for different sheath gas flow rates. With increasing power, the radial peak temperature typically shifts towards the wall. The resistance of the torch rises whereas the inductance diminishes with increasing RF power. The overall dependency of the coupling efficiency to the RF power is also estimated. The stabilization of the plasma flow dependency to the sheath swirl flow was investigated. The incorporation of Helium (0.02%) into an Argon gas was established to minimize the energy lost in the sidewall. The number and spacing of induction coil numbers affects the temperature and flow field distribution. A valuable approach to designing and optimizing the induction plasma system is presented in the proposed study. The obtained results are fundamental to specify ICP torch design criteria needed for multi-material processing.

Evolution of field emitters on copper surface during conditioning

To understand the mechanism of structure conditioning under high-power RF fields, a cathode image beamline based on field emission current was built at Tsinghua University. Cathodes made of oxygen-free copper were conditioned on the beamline. To monitor the modification of the cathode surface during conditioning, a designed solenoid focused the field emission current from the cathode to a YAG screen 1m away. The experiment showed that strong field emitters spontaneously appeared after breakdowns occurred, and the emitters were eliminated with increasing RF power. These results suggest that the conditioning process converts subsurface defects into field emitters and eliminates the emitters to improve the gradient threshold of breakdown.

RF power transfer efficiency of H ion sources: fluid modeling of accelerator source geometries

The plasma in RF driven negative hydrogen ion sources is sustained via inductive coupling with large power levels of up to 100 kW and low frequencies around 1 MHz. This leads to currents of around 100 A flowing over the RF coil and corresponding voltages in the kV range. The associated risk of arcing limits the reliability of the whole ion source. The required power level can be reduced via optimizing the RF power transfer efficiency η, which is typically only in the range of 50 to 60% for H- sources used for neutral beam injection systems. In order to study the optimization of η systematically, a self-consistent fluid model has been set up and successfully validated with experimental measurements at the BATMAN Upgrade test bed. For H- sources applied at particle accelerators, no experimental measurements of η are available so far. In order to gain a first insight into the RF power transfer efficiency of these sources, exemplary simulations were carried out with the fluid code. The simulated plasma parameters are in good agreement with results from OES measurements. η shows an increasing trend with larger source radius and a virtually constant value with increasing RF power. For benchmarking these first results, dedicated measurements at an accelerator source setup are inevitable.

Performance of RF sputtered V2O5 interface layer in p-type CdTe/Ag Schottky diode

In this work, vanadium pentoxide (V2O5) thin films were successfully grown on soda-lime glass by RF magnetron sputtering technique under an oxygen partial pressure of 10−6 m-bar at room temperatures. Systematically, the characterization of V2O5 films was carried out to study the impact of different sputtered power on the growth, structural and optical properties. XRD results revealed that films exhibit a preferred orientation along with the (001) plane, including an orthorhombic structure at the low RF power. The crystal growth corresponding (001) and (110) planes were suppressed as well as the intensity of peak (003) and (401) planes increased with increasing RF power. It was examined that at the high RF power, thin films show mixed oxide of VO2 and V2O5. A uniform spherical grains morphology was observed by FESEM micrographs. The thin films exhibited good transmittance above 80%, and a sharp absorption edge was found for all samples about 412 nm. Moreover, Two Schottky structures, Ag/V2O5/CdTe and Ag/CdTe were fabricated to investigate the performance of Schottky diode (SD) with the V2O5 interface layer between metal and semiconductor junctions for solar cell applications. The SD parameters such as ideality factor, barrier height, and interface resistance were also calculated. It was found that Ag/V2O5/CdTe diode performs well at room temperature. The saturation current increases from 1.03 μA to 8.39 μA with the insertion of the V2O5 interface layer (IF). Consequently, the V2O5 layer plays a vital role in enhancing the diode's performance.

Atomic layer etching technique for InAlN/GaN heterostructure with AlN etch-stop layer

An atomic layer etching (ALE) technique for InAlN/AlN/GaN structure was investigated for the first time. Different recipes with O2 modification times of 30–180 s and BCl3 removal RF powers of 15–25 W were tested. For three optimized recipes—30 s O2 + 15 W BCl3 ALE, 90 s O2 + 20 W BCl3 ALE, and 180 s O2 + 25 W BCl3 ALE—with increasing RF power, the etching per cycle increased from 0.14 to 1.00 nm/cycle. At the same time, the surface root-mean-square roughness remained approximately 0.28 nm and was thus much lower than that of the as-grown InAlN surface (0.45 nm) and the surface obtained by the conventional BCl3 dry etching approach (0.69 nm). Atomic force microscopy, X-ray photoelectron spectroscopy, and scanning transmission electron microscopy with energy dispersive X-ray spectroscopy measurements demonstrated the etch-stop effect and verified that the under-etching ALE technique was the most efficient way to precisely control the InAlN etching depth and surface morphology. This finding has important implications for realizing high-performance InAlN/GaN high electron mobility transistors.

Synthesis of visible spectrum-active TiO2 thin film induced by RF magnetron sputtering

TiO2 anatase phase has a key role in environmental and photocatalysis research. But, the TiO2 anatase phase is not able to give photocatalytic activity in the visible spectrum as it has a large bandgap, i.e., 3.2 eV which is the main drawback of it. Thus, if some method could decrease the bandgap of anatase, TiO2 - able to photocatalysis in the visible light irradiation. Hence, visible spectrum-active TiO2 (visi-TiO2) thin films on corning glass were deposited using RF magnetron sputtering in the present study. The visi- TiO2 was deposited at various RF powers (60, 120, 180, 200, and 300 W) and characterized using X-ray diffraction (XRD), UV–vis spectroscopy, and dye degradation under visible light. The XRD spectrum confirmed that an increase in RF power was generated phase transformation from rutile to anatase. The bandgap energy was calculated by the Tauc method, and the direct optical band gap of the visi- TiO2 film was observed to decrease from 3.15 to 2.87 eV as an increase in RF power. The visible light absorption edge in all Visi- TiO2 thin films is due to surface morphology. Photocatalytic activity of Visi-TiO2 film has been explored by degradation of direct blue 14 azo dye in aqueous solution as a contaminant of water in presence of visible spectrum irradiation. The photocatalytic degradation potential of Visi-TiO2 film was found to be 99% after 210 min. The newly discovered low bandgap anatase phase can be achieved by changing the sputtering parameters. The synthesis of a TiO2 anatase phase with a bandgap belongs to the visible and more chemical reactivity has implications for its use as a photocatalyst and artificial photosynthesis.

(Invited) High-Speed Plasma Etching of SiC Wafer Toward Backside Thinning

Semiconductor power devices are necessary to convert electric voltage, current, and frequency for efficient electrical energy use. Although most of them are now fabricated using silicon (Si) semiconductors, wide bandgap semiconductors such as silicon carbide (SiC) and gallium nitride (GaN), which have a larger bandgap than Si, are attracting attention for efficient conversion improvement. Continuous research and development of crystal growth, crystal evaluation, and device improvement technologies over many years have led to the commercialization of SiC transistors and inverters. One of the issues of SiC power devices is their comparatively higher cost than Si power devices; therefore, reducing the cost is essential for their wide application. Not only high quality and low-cost crystal growth technology is essential for SiC power devices but also a low-cost processing technique. Most power transistors have a vertical structure. Device wafer substrate thickness must be thin to minimize onstate resistance; however, there is a limiting thickness necessary for handling a wafer during device processing. Therefore, wafer thickness must be reduced from a backside after devices are fabricated on it. Although a mechanical process such as grinding is suitable for the backside thinning of silicon, it is costly for SiC because of extended processing time due to its hardness and the high wear rate of an expensive diamond grinding wheel. Additionally, the process leaves subsurface damage on a processed surface, decreasing device chip strength and reliability.We investigated the applications of plasma chemical vaporization machining (PCVM), a plasma etching method using high-pressure plasma, to the SiC backside thinning process. In conventional plasma etching for device fabrication, reactive ion etching (RIE) is employed to ensure anisotropy, an important requirement for pattern transferability. In the RIE process, applied pressure cannot be increased because the mean-free path of the gas molecules must be long enough for ion acceleration. Owing to the limited amount of gas molecules contributing to the reaction, the processing rate is limited to approximately 1 μm/min. PCVM is a chemical etching process in which neutral radicals are employed as the active species. Although it lacks anisotropy, an etching rate that is difficult to achieve with RIE can be attained by increasing working pressure. We developed a wafer-sized electrode, i.e., an electrode with the same surface geometry as a wafer, with many gas supply holes fabricated for wafer-level thinning. It was found that the SF6 plasma generated over the entire wafer surface by reducing the working pressure from atmospheric pressure to a few tenths of the atmospheric pressure without helium dilution. The results of the experiments showed that the thickness of the entire 2-inch 4H-SiC (0001) wafer could be reduced at a high removal rate of 15 μm/min by increasing rf power. The removal rate mainly depended on power density and was relatively insensitive to the processing parameters such as processing gap and gas flow rate. In addition, it was discovered that almost the same removal rate could be achieved with rf power being proportional to the area of the wafer even if the wafer diameter was increased. It was demonstrated that the thickness of the commercially available two-inch wafer could be thinned to approximately 100 μm by 20-min plasma etching. Furthermore, a commercially available SiC MOSFET chip was used for a backside thinning experiment to evaluate the influence of plasma irradiation on the MOS interface using the C–V characteristic measurements. Although the deterioration of the SiO2/SiC interfacial properties due to ultraviolet (UV) irradiation was reported, there was no change in the C–V characteristic before and after exposure to SF6 plasma. The constant C–V characteristic might be because the amount of UV light reaching from the backside to frontside surface is small owing to the thin penetration depth.PCVM for the backside thinning of a SiC wafer contributes to cost reduction owing to reduction in processing time and the nonuse of an expensive diamond grinding wheel. It also improves the reliability of fabricated devices because it leaves no subsurface damage on the backside of a wafer, resulting in the wide-spread utilization of low-power consumption SiC power devices for a sustainable society.