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Showing papers on "Diode published in 2010"


Journal ArticleDOI
TL;DR: In this paper, high efficiency solar cells with up to 6.8% efficiency were obtained with absorber layer thicknesses less than 1μm and annealing times in the minutes.
Abstract: High efficiency Cu2ZnSnS4 solar cells have been fabricated on glass substrates by thermal evaporation of Cu, Zn, Sn, and S. Solar cells with up to 6.8% efficiency were obtained with absorber layer thicknesses less than 1 μm and annealing times in the minutes. Detailed electrical analysis of the devices indicate that the performance of the devices is limited by high series resistance, a “double diode” behavior of the current voltage characteristics, and an open circuit voltage that is limited by a carrier recombination process with an activation energy below the band gap of the material.

588 citations


Journal ArticleDOI
TL;DR: In this paper, an organic light-emitting diodes featuring layers with a spontaneously formed buckled geometry are demonstrated to offer at least a twofold improvement in light extraction efficiency across the entire visible spectrum.
Abstract: Organic light-emitting diodes featuring layers with a spontaneously formed buckled geometry are demonstrated to offer at least a twofold improvement in light extraction efficiency across the entire visible spectrum.

560 citations


Journal ArticleDOI
TL;DR: In this paper, a numerical model for the efficiency analysis of organic light-emitting diodes (OLEDs) was proposed and compared with experimental data measured on red state-of-the-art p-i-n devices containing the red phosphorescent emitting dye iridium(III)bis[2-methyldibenzo-(f, h)quinoxaline](acetylacetonate) [Ir(MDQ)2(acac)].
Abstract: The external quantum efficiency of organic light-emitting diodes (OLEDs) is limited by several loss mechanisms. By applying a numerical model for the efficiency analysis of OLED devices, we analyze the distribution of the different energy loss mechanisms in bottom and top emission organic light-emitting diodes. We validate the findings by the comparison with experimental data measured on red state-of-the-art p-i-n devices containing the red phosphorescent emitting dye iridium(III)bis[2-methyldibenzo-(f, h)quinoxaline](acetylacetonate) [Ir(MDQ)2(acac)]. The model is used to design extremely efficient bottom and top emission diodes with 21% and 27% external quantum efficiencies, respectively.

293 citations


Journal ArticleDOI
TL;DR: In this paper, a graded emitter and thin barriers were introduced in GaInAs/AlAs double-barrier resonant tunneling diodes for reducing the transit time in the collector depletion region and the tunneling time, respectively.
Abstract: Fundamental oscillations up to 1.04 THz were achieved in resonant tunneling diodes at room temperature. A graded emitter and thin barriers were introduced in GaInAs/AlAs double-barrier resonant tunneling diodes for reductions of the transit time in the collector depletion region and the resonant tunneling time, respectively. Output powers were 7 μW at 1.04 THz and around 10 μW in 0.9–1 THz region. A change in oscillation frequency of about 4% with bias voltage was also obtained.

277 citations


Journal ArticleDOI
TL;DR: In this paper, a 250 and 262 nm deep-ultraviolet (DUV) AlGaN multi-quantum well (MQW) light-emitting diodes (LEDs) fabricated on AlN/sapphire templates by introducing multiquantum-barrier (MQB) electron blocking layers (EBLs).
Abstract: We demonstrated high-efficiency 250–262 nm deep-ultraviolet (DUV) AlGaN multi-quantum well (MQW) light-emitting diodes (LEDs) fabricated on AlN/sapphire templates by introducing multiquantum-barrier (MQB) electron-blocking layers (EBLs). A marked enhancement in efficiency, by as much as 2.7 times, was observed for a 250 nm AlGaN LED by replacing the usual "single-barrier" EBL with a MQB-EBL. The maximum external quantum efficiencies and output powers of LEDs with MQB-EBLs measured under room temperature (RT) cw operation were 1.18% and 4.8 mW, and 1.54% and 10.4 mW, for the 250 nm and 262 nm LEDs, respectively, which are the highest values ever reported.

260 citations


Journal ArticleDOI
TL;DR: In this article, a moth-eye structure was fabricated on the back side of the sapphire substrate, and on-wafer output power measurement indicated a 1.5-fold improvement of light extraction.
Abstract: We report on the fabrication and characterization of AlGaN-based deep ultraviolet light-emitting diodes (LEDs) with the emission wavelength ranging from 255 to 280 nm depending on the Al composition of the active region. The LEDs were flip-chip bonded and achieved external quantum efficiencies of over 3% for all investigated wavelengths. Under cw operation, an output power of more than 1 mW at 10 mA was demonstrated. A moth-eye structure was fabricated on the back side of the sapphire substrate, and on-wafer output power measurement indicated a 1.5-fold improvement of light extraction.

247 citations


Journal ArticleDOI
TL;DR: In this paper, the impact of device size scaling on the light output, spectral shift, and self-heating of 400 nm InGaN light-emitting diodes (LEDs) was systematically investigated.
Abstract: We have systematically investigated the impact of device size scaling on the light output, spectral shift, and self-heating of 400 nm InGaN light-emitting diodes (LEDs). Devices with diameters in the range 20-300 µm have been studied. It is shown that smaller LED pixels can deliver higher power densities (despite the lower absolute output powers) and sustain higher current densities. Investigations of the electroluminescence characteristics of differently sized pixels against current density reveal that the spectral shift is dominated by blueshift at the low current density level and then by redshift at the high current density level, owing to the competition between the bandgap shrinkage caused by self-heating and band-filling effects. The redshift of the emission wavelength with increasing current density is much faster and larger for the bigger pixels, suggesting that the self-heating effect is also size dependent. This is further confirmed by the junction-temperature rise measured by the established spectral shift method. It is shown that the junction-temperature rise in smaller pixels is slower, which in turn explains why the smaller redshift of the emission wavelength with current density is present in smaller pixels. The measured size-dependent junction temperature is in reasonable agreement with finite element method simulation results.

232 citations


Journal ArticleDOI
TL;DR: In this paper, a carrier loss process modeling density-activated defect recombination can reproduce the experimentally observed droop of the internal quantum efficiency in GaN-based laser diodes.
Abstract: It is shown that a carrier loss process modeling density-activated defect recombination can reproduce the experimentally observed droop of the internal quantum efficiency in GaN-based laser diodes.

211 citations


Journal ArticleDOI
TL;DR: In this paper, a graded-composition electron blocking layer (GEBL) with aluminum composition increasing along the [0001] direction was designed for c-plane InGaN/GaN light-emitting diodes (LEDs) by employing the band-engineering.
Abstract: A graded-composition electron blocking layer (GEBL) with aluminum composition increasing along the [0001] direction was designed for c-plane InGaN/GaN light-emitting diodes (LEDs) by employing the band-engineering. The simulation results demonstrated that such GEBL can effectively enhance the capability of hole transportation across the EBL as well as the electron confinement. Consequently, the LED with GEBL grown by metal-organic chemical vapor deposition exhibited lower forward voltage and series resistance and much higher output power at high current density as compared to conventional LED. Meanwhile, the efficiency droop was reduced from 34% in conventional LED to only 4% from the maximum value at low injection current to 200 A/cm2.

210 citations


Journal ArticleDOI
TL;DR: A new level of control over electrical carrier injection is achieved, reducing power dissipation by a factor of up to 1,000, and resulting in zero threshold current, negligible self-heating and high carrier-to-photon conversion efficiencies.
Abstract: Electrically induced light emission from an individual carbon nanotube p–n diode is both more efficient and has a narrower spectrum than previously demonstrated, allowing emission from free and localized excitons to be identified.

207 citations


Journal ArticleDOI
Bo Zhu, Yijun Feng1, Junming Zhao, Ci Huang, Tian Jiang 
TL;DR: In this article, a controllable electromagnetic wave reflector/absorber for different polarizations with metamaterial involving electromagnetic resonant structures coupled with diodes was demonstrated, which can switch the structure between nearly total reflection and total absorption of a particularly polarized incident wave.
Abstract: We demonstrate a controllable electromagnetic wave reflector/absorber for different polarizations with metamaterial involving electromagnetic resonant structures coupled with diodes. Through biasing at different voltages to turn ON and OFF the diodes, we are able to switch the structure between nearly total reflection and total absorption of a particularly polarized incident wave. By arranging orthogonally orientated resonant cells, the metamaterial can react to different polarized waves by selectively biasing the corresponding diodes. Both numerical simulations and microwave measurements have verified the performance.

Journal ArticleDOI
TL;DR: In this article, a lateral Schottky-based rectifier called the charge-plasma diode realized on ultrathin silicon-on-insulator was proposed, which utilizes the workfunction difference between two metal contacts, palladium and erbium, and the silicon body.
Abstract: We present a new lateral Schottky-based rectifier called the charge-plasma diode realized on ultrathin silicon-on-insulator. The device utilizes the workfunction difference between two metal contacts, palladium and erbium, and the silicon body. We demonstrate that the proposed device provides a low and constant reverse leakage-current density of about 1 fA/μm with ON/OFF current ratios of around 107 at 1-V forward bias and room temperature. In the forward mode, a current swing of 88 mV/dec is obtained, which is reduced to 68 mV/dec by back-gate biasing.

Journal ArticleDOI
TL;DR: In this paper, a new silicon depletion-mode vertical p-n junction phase-modulator implemented in Mach-Zehnder modulator configuration, enabling an ultralow measured V? L of only ~ 1 V·cm.
Abstract: Through rigorous process, electrical, and optical simulations, we develop a new silicon depletion-mode vertical p-n junction phase-modulator implemented in Mach-Zehnder modulator configuration, enabling an ultralow measured V ? L of only ~ 1 V·cm. Further, in a 500-?m-long lumped element device, we demonstrate a 10-Gb/s nonreturn-to-zero data transmission with wide-open complementary output eye diagrams without the use of signal preemphasis.

Posted Content
TL;DR: In this paper, a new level of control over electrical carrier injection is achieved, reducing power dissipation by a factor of up to 1000 and resulting in zero threshold current, negligible self-heating, and high carrier-to- photon conversion efficiencies.
Abstract: Electrically-driven light emission from carbon nanotubes could be exploited in nano-scale lasers and single-photon sources, and has therefore been the focus of much research. However, to date, high electric fields and currents have been either required for electroluminescence, or have been an undesired side effect, leading to high power requirements and low efficiencies. In addition, electroluminescent linewidths have been broad enough to obscure the contributions of individual optical transitions. Here, we report electrically-induced light emission from individual carbon nanotube p-n diodes. A new level of control over electrical carrier injection is achieved, reducing power dissipation by a factor of up to 1000, and resulting in zero threshold current, negligible self-heating, and high carrier-to- photon conversion efficiencies. Moreover, the electroluminescent spectra are significantly narrower (ca. 35 meV) than in previous studies, allowing the identification of emission from free and localized excitons.

Journal ArticleDOI
TL;DR: In this paper, a single-switch non-isolated dc-dc converter with high voltage transfer gain and reduced semiconductor voltage stress is proposed, which utilizes a hybrid switched-capacitor technique for providing a high voltage gain without an extreme switch duty cycle and yet enabling the use of a lower voltage and RDS-ON MOSFET switch.
Abstract: In this paper, a new single-switch nonisolated dc-dc converter with high voltage transfer gain and reduced semiconductor voltage stress is proposed. The proposed topology utilizes a hybrid switched-capacitor technique for providing a high voltage gain without an extreme switch duty cycle and yet enabling the use of a lower voltage and RDS-ON MOSFET switch so as to reduce cost, switch conduction, and turn-on losses. In addition, the low voltage stress across the diodes allows the use of Schottky rectifiers for alleviating the reverse-recovery current problem, leading to a further reduction in the switching, and conduction losses. The principle of operation and a comparison with other high step-up topologies are presented. Two extensions of the proposed converter are also introduced and discussed. Simulation and experimental results are also presented to demonstrate the effectiveness of the proposed scheme.

Journal ArticleDOI
TL;DR: In this paper, the design and demonstration of polarization-engineered GaN/InGaN/GaN tunnel junction diodes with high current density and low tunneling turn-on voltage was reported.
Abstract: We report on the design and demonstration of polarization-engineered GaN/InGaN/GaN tunnel junction diodes with high current density and low tunneling turn-on voltage. Wentzel–Kramers–Brillouin calculations were used to model and design tunnel junctions with narrow band gap InGaN-based barrier layers. N-polar p-GaN/In0.33Ga0.67N/n-GaN heterostructure tunnel diodes were grown using molecular beam epitaxy. Efficient interband tunneling was achieved close to zero bias with a high current density of 118 A/cm2 at a reverse bias of 1 V, reaching a maximum current density up to 9.2 kA/cm2. These results represent the highest current density reported in III-nitride tunnel junctions and demonstrate the potential of III-nitride tunnel devices for a broad range of optoelectronic and electronic applications.

Journal ArticleDOI
TL;DR: In this article, a review of recent advances in p-type ohmic-contact technology for GaN-based LEDs is presented, where a variety of methods for forming transparent and reflective ohmic contacts are introduced.
Abstract: GaN-based semiconductors are of great technological importance for the fabrication of optoelectronic devices, such as light-emitting diodes (LEDs) and laser diodes. The further improvement of LED performance can be achieved through the enhancement of external quantum efficiency. In this regard, high-quality p-type ohmic electrodes having low contact resistance and high transmittance (or reflectivity), along with thermal stability, must be developed because p-type ohmic contacts play a key role in the performance of LEDs. In this paper, we review recent advances in p-type ohmic-contact technology for GaN-based LEDs. A variety of methods for forming transparent and reflective ohmic contacts are introduced.

Journal ArticleDOI
TL;DR: In this paper, a single phase of ZnO microring with outer diameter ranging from 2.2μm to 1.72μm and inner diameters ranging from 125nm to 470nm was obtained.

Journal ArticleDOI
TL;DR: In this paper, a Ti/TiO2/Pt oxide diode with excellent rectifying characteristics was fabricated by the asymmetric Schottky barriers at the Ti/ TiO2 (0.13 eV) interfaces.
Abstract: We have fabricated a Ti/TiO2/Pt oxide diode with excellent rectifying characteristics by the asymmetric Schottky barriers at the Ti/TiO2 (0.13 eV) and the TiO2/Pt (0.73 eV) interfaces. Instead of homogeneous conduction, the current transport is governed by the localized oxygen-deficient TiO2 filaments. In addition, the reproducible resistive-switching exists in the same structure, triggered by the forming process. The transition between two modes is ascribed to the destruction of the interface barriers at forming. The rectification stable up to 125 °C and 103 cycles under ±3 V sweep without interference with resistive-switching shows satisfactory reliability of TiO2 diodes for one diode-one resistor memory devices.

Journal ArticleDOI
TL;DR: In this article, an interconnecting unit between two vertically stacked OLEDs, consisting of an abrupt heterointerface between a Cs2CO3-doped 4,7-diphenyl-1,10-phenanthroline layer and a WO3 film, is investigated.
Abstract: The mechanism of charge generation in transition metal oxide (TMO)-based charge-generation layers (CGL) used in stacked organic light-emitting diodes (OLEDs) is reported upon. An interconnecting unit between two vertically stacked OLEDs, consisting of an abrupt heterointerface between a Cs2CO3-doped 4,7-diphenyl-1,10-phenanthroline layer and a WO3 film is investigated. Minimum thicknesses are determined for these layers to allow for simultaneous operation of both sub-OLEDs in the stacked device. Luminance–current density–voltage measurements, angular dependent spectral emission characteristics, and optical device simulations lead to minimum thicknesses of the n-type doped layer and the TMO layer of 5 and 2.5 nm, respectively. Using data on interface energetic determined by ultraviolet photoelectron and inverse photoemission spectroscopy, it is shown that the actual charge generation occurs between the WO3 layer and its neighboring hole-transport material, 4,4',4”-tris(N-carbazolyl)-triphenyl amine. The role of the adjacent n-type doped electron transport layer is only to facilitate electron injection from the TMO into the adjacent sub-OLED.

Journal ArticleDOI
TL;DR: In this article, the Schottky barrier height of 0.42 V and ideality factor of 1.6 at room temperature was obtained for a single ZnO nanowire with a response time of ∼55 s.
Abstract: Vertically aligned ZnO nanowires were grown on c-plane sapphire substrate by metal organic chemical vapor deposition technique. The nanowires were single crystalline and structurally uniform and did not exhibit any noticeable defects. Pt/ZnO single nanowire Schottky diodes were fabricated by using e-beam lithography and then characterized by measuring temperature-dependent I−V characteristics. The diode exhibited a low Schottky barrier height of 0.42 V and ideality factor of 1.6 at room temperature. Temperature-dependent hydrogen-sensing measurements were carried out with different hydrogen concentrations. A good sensing characteristic (S ≈ 90%) has been observed at room temperature with a response time of ∼55 s.

Patent
24 Nov 2010
TL;DR: In this article, a light-emitting diode with good heat radiation property and light emission characteristics, and capable of realizing high productivity and yields, is proposed to provide a light emitting diode having good heat radii and light emissions characteristics.
Abstract: PROBLEM TO BE SOLVED: To provide a light-emitting diode having good heat radiation property and light emission characteristics, and capable of realizing high productivity and yields.SOLUTION: A light-emitting diode 100 has a wiring layer 31, and a semiconductor light-emitting element 10 on the wiring layer 31. The semiconductor light-emitting element 10 has a semiconductor light-emitting layer 6, a transparent conductive layer 8, a metal reflective layer 9, a transparent insulation film 11, and a first electrode part 21 and a second electrode part 22 provided on the wiring layer 31 side of the transparent insulation film 11 via separation regions 18 and 19 and electrically connected to the wiring layer 31. The first electrode part 21 is electrically connected to a first semiconductor layer 5 via the transparent conductive layer 8 by a first contact part 14. The second electrode part 22 is electrically connected to a second semiconductor layer 3 by a second contact part 15 provided to penetrate through the transparent insulation film 11 and to be insulated from and penetrate through the transparent conductive layer 8, the first semiconductor layer 5, and an active layer 4.

Journal ArticleDOI
TL;DR: In this paper, the degradation of bottom-emitting organic light emitting diodes with different polymeric hole injection layers was investigated using impedance spectroscopy, and it was shown that the loss of luminance and increase in drive voltage of stressed devices is accompanied by a deterioration of hole injection and the formation of positively charged quenching centers at or close to the organic heterojunction.
Abstract: Impedance spectroscopy is a powerful method for characterizing the electrical properties of materials and their interfaces. In this study we use capacitance measurements to investigate the degradation of electrically aged bottom-emitting organic light-emitting diodes with different polymeric hole injection layers. The devices comprise a heterojunction between a hole transporting triphenyl-diamine and an electron transporting and green emitting aluminum chelate complex [Alq3, tris-(8-hydroxyquinoline) aluminum]. A detailed analysis of the capacitance as function of frequency and dc bias yields information about trapped and interfacial charges as well as the dynamics of injected charges. We find that the loss of luminance and the increase in drive voltage of stressed devices is accompanied by a deterioration of hole injection and the formation of positively charged quenching centers at or close to the organic heterojunction. Using a new polymeric hole injection layer leads to improved device stability.

Journal ArticleDOI
Akira Fujioka1, Takao Misaki1, Takashi Murayama1, Yukio Narukawa1, Takashi Mukai1 
TL;DR: In this article, a 280-nm light-emitting diodes (LEDs) were fabricated by employing high-crystal-quality AlN templates and optimized epitaxial structures.
Abstract: We fabricated high-output-power 280-nm light-emitting diodes (LEDs) by employing high-crystal-quality AlN templates and optimized epitaxial structures. The emission wavelength, output power, forward voltage, spectral linewidth, and external quantum efficiency of the fabricated device measured at 20 mA were 281.0 nm, 2.45 mW, 7.53 V, 10.6 nm, and 2.78%, respectively. In the case of DC operation, the output power increased with time probably resulting from enhanced p-type activation by junction heating. We also fabricated a multi-chip device which consisted of 26 small-chip LEDs. It produced 223 mW at a pulse injection current of 1850 mA.

Journal ArticleDOI
TL;DR: In this paper, an epitaxial design and material quality on a c-plane GaN substrate was proposed for green laser diodes with an emission wavelength of 531.7 nm and wall plug efficiency up to 2.3% at 50 mW optical output power.
Abstract: We pushed direct green laser diodes towards longer wavelengths at 524–532 nm based on improvements of epitaxial design and material quality on c-plane GaN substrate. Mounted ridge laser diodes show significant performance improvement in cw operation. For 524 nm laser, wall plug efficiency up to 2.3% at 50 mW optical output power is achieved. In pulse mode operation we demonstrate broad-area test lasers with an emission wavelength of 531.7 nm. Nonpolar and polar substrates are compared with respect to indium content in InGaN quantum wells. The limiting factors for achieving longer wavelengths and better performance of green lasers are discussed from this viewpoint.

Journal ArticleDOI
TL;DR: In this article, a superluminescent diodes were fabricated using active multimode interferometers that emit at a wavelength of 1.55? m. The output power as high as 115 mW was obtained with a wide 3dB bandwidth of 50 nm and low spectral ripple of 0.03 dB.
Abstract: We have designed and fabricated, for the first time to our knowledge, novel superluminescent diodes by using active multimode interferometers that emit at a wavelength of 1.55 ? m. An output power as high as 115 mW was obtained with a wide 3-dB bandwidth of 50 nm and low spectral ripple of 0.03 dB. In addition, they showed stable single-transverse-mode outputs up to the maximum output power.

Journal ArticleDOI
TL;DR: It is shown here that it is possible to access a suffi ciently low intensity regime to be of relevance to the operation mechanism of OPVs under solar illumination and that charge lifetimes are extended under reverse bias, revealing that the mechanism of photocurrent generation is the electric fi eld-assisted separation of Coulombically bound charge pairs in kinetic competition with geminate charge recombination.
Abstract: Efforts to improve OPV cells must be underpinned by a clear and quantitative understanding of photocurrent generation and loss mechanisms, in particular the mechanism by which the electric fi eld determines the current-voltage characteristics of OPV cells. While the processes of photon absorption to create excitons, and exciton dissociation to create electrons and holes across donor-acceptor interfaces are well understood and independent of electric fi eld, [ 3 ] there are confl icting models for what happens subsequently. On the one hand, if interfacial charge pairs are Coulombically bound, the effect of an electric fi eld would be to dissociate geminate charge pairs and allow them to contribute to photocurrent. [ 4–10 ] On the other hand, if photoinduced charge transfer leads to fully separated electrons and holes, independent of electric fi eld, then the observed effect of the electric fi eld must be to suppress bimolecular recombination during charge extraction. [ 11–16 ] Here, we present the biasdependence of time-resolved optical absorption spectroscopy in a working OPV device. This technique allows us to distinguish between the two models of photocurrent generation by directly observing the effect of an electric fi eld on charge dynamics. This is a challenging experiment because, as we demonstrate below, the high instantaneous excitation densities generally required in transient optical absorption spectroscopy can greatly reduce PV effi ciency. Yet, the extent to which pulse energies can be attenuated to mitigate the effect of strongly modulated excitation densities is constrained by the sensitivity of signal detection. We show here that it is possible to access a suffi ciently low intensity regime to be of relevance to the operation mechanism of OPVs under solar illumination. We fi nd that charge lifetimes are extended under reverse bias, revealing that the mechanism of photocurrent generation is the electric fi eld-assisted separation of Coulombically bound charge pairs in kinetic competition with geminate charge recombination. The pertinent details of the sample OPV device and the experimental capabilities we have established are detailed in Figure 1a . Direct optical probes of photoexcitations in OPV

Journal ArticleDOI
TL;DR: It is expected that this type of Schottky diode effectively suppresses the sneak current without adverse interference effects in a nano-scale resistive switching cross-bar array with high block density.
Abstract: This study examined the properties of Schottky-type diodes composed of Pt/TiO2/Ti, where the Pt/TiO2 and TiO2/Ti junctions correspond to the blocking and ohmic contacts, respectively, as the selection device for a resistive switching cross-bar array. An extremely high forward-to-reverse current ratio of ~ 109 was achieved at 1 V when the TiO2 film thickness was 19 nm. TiO2 film was grown by atomic layer deposition at a substrate temperature of 250 °C. Conductive atomic force microscopy revealed that the forward current flew locally, which limits the maximum forward current density to < 10 A cm − 2 for a large electrode (an area of ~ 60 000 µm2). However, the local current measurement showed a local forward current density as high as ~ 105 A cm − 2. Therefore, it is expected that this type of Schottky diode effectively suppresses the sneak current without adverse interference effects in a nano-scale resistive switching cross-bar array with high block density.

Journal ArticleDOI
TL;DR: In this article, a new thermal model based on the Fourier series solution of heat conduction equation has been introduced in detail, which can provide high simulation speed with high accuracy, which has proved to be more favorable in dynamic thermal characterization on power semiconductor switches.
Abstract: In this paper, a new thermal model based on the Fourier series solution of heat conduction equation has been introduced in detail. 1-D and 2-D Fourier series thermal models have been programmed in MATLAB/Simulink. Compared with the traditional finite-difference thermal model and equivalent RC thermal network, the new thermal model can provide high simulation speed with high accuracy, which has been proved to be more favorable in dynamic thermal characterization on power semiconductor switches. The complete electrothermal simulation models of insulated gate bipolar transistor (IGBT) and power diodes under inductive load switching condition have been successfully implemented in MATLAB/Simulink. The experimental results on IGBT and power diodes with clamped inductive load switching tests have verified the new electrothermal simulation model. The advantage of Fourier series thermal model over widely used equivalent RC thermal network in dynamic thermal characterization has also been validated by the measured junction temperature.

Journal ArticleDOI
TL;DR: The electrical and photovoltaic properties of the nanostructure ZnO/p-Si diode have been investigated in this paper, where the ideality factor and barrier height of the diode were found to be 3.18 and 0.78 eV respectively.