Papers by Keyword: Capacitance-Voltage

Abstract: Electrically active defects at the SiO₂/SiC interface can have detrimental effects on the device performance of SiC MOSFETs. Capacitance-or conductance-based analysis techniques are commonly used to extract the density of interface defects, despite having the disadvantage of requiring dedicated test structures for the analysis. Here, we discuss confocal sub-bandgap photoluminescence (PL) microscopy as a fast and reliable alternative to conventional electrical characterization techniques. For this purpose, the quality of the SiO₂/SiC interface after post-oxidation annealing in N₂O is studied both by confocal imaging as well as by the high-low and C-Ψ capacitance technique. We find excellent agreement between the optical and electrical analysis and observe a significant increase of the interface defect density for annealing temperatures below 1050 °C. Keywords: interface defect density, photoluminescence, capacitance-voltage

Abstract: MeV level aluminum implants into 4H-SiC were performed as part of superjunction diode fabrication. Measurement of resistance test structures produced resistivities well above expected values with large decreases at elevated temperatures. Capacitance-voltage measurements indicate a high activation rate of the implanted aluminum. Temperature dependent Hall measurements produce reasonable hole mobilities with acceptor ionization energies of approximately 330meV, well above the 200meV expected for low concentration aluminum doping in 4H-SiC.

Abstract: Nitride-based light emitting diodes (LEDs) is an attractive material due to its high temperature tolerance and suitable to be used in extreme environment. The irradiation process of Gallium Nitride (GaN) diode was carried out by electron irradiation with 1000 kGy and 1500 kGy doses with a conveyor speed of 50 kGy per pass. Capacitance-voltage (C-V) and current-voltage (I-V) characterization for both pre and post irradiation samples was done. Both current and capacitance show decreasing while reverse leakage current increased after irradiation. The reverse leakage current revealed that the current were start leakage at 1.0 x10 ^-7 A and 1.0 x10^-9 A for 1000 kGy and 1500 kGy irradiations respectively. The current-voltage graph indicated that the effect of electron irradiation on diode produced weak spots as defect cause leakage current. The traps and bulk defect is believed to contributed to the leakage current increased.

Abstract: The purpose of the paper is present the new result of electrical properties of Pt-doped silicon Schottky diodes that are fabricated by using CMOS technology. The results show the comparison of electrical properties namely current-voltage and capacitance characteristics between undoped and Pt-doped Schottky diode. The current characteristics of Pt-doped diode are decreased about 2 to 3 orders in term of reverse bias. As well as in case of forward bias, the current is slightly decreased. Schottky barrier height after Pt doping was increased from 0.84 eV to 0.86 eV. The built-in voltage of Pt-doped diodes was increased from 0.38 V to 0.42 V. The C-V characteristics after Pt doping is decreased about 5 pF. The change of electrical properties are caused by Pt because Pt atoms in silicon can occupy interstitial sites and change the trapping center. This paper will study and analyze the effect of Pt atom in silicon bulk of Schottky diode.

Abstract: The electrical and optical characteristics of indium doped Se₂Sb₂Te₆ phase-change alloy are studied. It is found that adding indium to Se2Sb2Te6 alloy (In_0.3Se₂Sb₂Te₆) increased the crystallization temperature and reduced the electrical conduction activation energy. The capacitance-temperature measurements showed a drastic change in the capacitance of the modified film when the temperature approaches the crystallization temperature, and eventually the capacitance becomes negative and nonlinear. The negativity and nonlinearity in the capacitancevoltage dependence can be attributed to the growth of conductive crystalline islands by increasing the temperature.

Abstract: This paper studies the electronic properties of MOS capacitors fabricated on double positioning boundary free 3C-SiC/6H-SiC where the 3C-SiC films were grown using the Vapour- Liquid-Solid mechanism. The temperature- and frequency-dependent electrical properties of SiO2/3C-SiC/6H-SiC structures have been studied. Capacitance measurements indicate that the single-domain 3C-SiC film is doped near the surface with an average concentration of 8.3 × 1016 cm-3. The measured interface state density near the conduction band edge of 3C-SiC is below 1011cm-2⋅eV-1 and increases towards mid-gap as obtained from conductance and capacitance measurements. Our results are consistent with the assumption that the interfaces of SiO2/ n-type SiC consist of two different kinds of interface traps – the carbon clusters located at the interface and the intrinsic defects located within the oxide layer.

Abstract: Dielectric charges and charge stability were compared in different dielectrics formed on SiC by different processing techniques. The concentration and transient behavior of the interface and trapped charges were investigated. Strong hysteresis and flat-band voltage drift under applied bias were observed in some of the samples. They are attributed to the trapping of the charge injected in the dielectrics. Differences in charge injection, charge trapping, and capture/emission of carriers by interface traps were pronounced for the investigated SiO2 and Si3N4 dielectrics.