PIN Junction Diodes Research Articles

High-performance alpha-voltaic cell based on a 4H-SiC PIN junction diode

Alpha-voltaic cells have great potential in military, biomedical, and infrastructure applications due to their characteristics of long operating life, small volume, and superior adaptability. However, improvements in power conversion efficiency (PCE), and the balance between power density and stability have been a challenge owing to the ‘poor-matching’ between energy conversion transducers and alpha-emitting isotope sources, as well as the radiation damage to semiconductor devices. In this study, we report the electrical properties of a high-performance alpha-voltaic cell based on a 4H-SiC PIN junction diode energy conversion transducer (active area of 1 cm2) that has been experimentally validated by a He ions electrostatic accelerator. Remarkably, the alpha-voltaic cell displayed an excellent PCE of 0.88%, exhibiting a nearly 7-fold enhancement compared to alpha-voltaic cells of previous studies, with a strikingly high open-circuit voltage of 1.99 V, a short-circuit current of 13.64 nA/cm2, and a maximum output power density of 16.78 nW/cm2.

WSe2 Homogeneous in-Plane Pin Junction Diode with Electric Double Layers

Transition metal dichalcogenide (TMDC) materials are in the spotlight as next-generation semiconductor materials because of their advantages over other semiconductor materials. Research on WSe2 among the materials is underway, and the feature of WSe2 has an ambipolar characteristic, and the fermi level change and the doping effect are different according to the electrode type.In the present study, we have fabricated a homogeneous WSe2 PIN junction diode. Our in-plane multilayer WSe2 p-i-n homogeneous diode exhibited photovoltaic properties by asymmetric physical contact doping effect with electric double layer(EDL). Owing to the EDL placed between the cathode and anode, local charge carrier type and density profile are modulated in the same layers.Compared to general diode mode, PIN mode enhance the photo response of the device in our visible measurement range. The diode exhibits excellent rectifying behavior with a current rectification ratio of 104 or higher. Photovoltaic performance of short circuit current and open circuit voltage achieved 3.2 nA, 0.55 V, respectively under the 550 nm green light. And spectrum responsivity is about ~100 mA/W (max point) at 3.2 eV to 1.6 eV. Figure 1

Improved electrical performance of MOCVD-grown GaN p-i-n diodes with high-low junction p-layers

We report that using a high/low p-type junction anode structure results in improved hole injection over a uniformly-doped p-anode layer in GaN pin junction diodes. Quasi-vertical diodes with a 20 nm thick, magnesium concentration of 2 × 1020 cm−3 layer on top of a 480 nm thick layer with a magnesium concentration of 1018 cm−3 show greatly increased forward current density – >100× higher – than those with a 500 nm thick uniformly 3 × 1019 cm−3 Mg-doped p-layer. Forward knee voltage and ideality factor are reduced by a factor of more than two, and reverse leakage current density is also reduced. Additionally, the specific differential series resistance is reduced significantly. With photoluminescence measurements, we found that these improvements are largely due to improved p-GaN material quality of the high/low junction sample with lower average Mg concentration.

Density Functional Theory Study on Defect Behavior Related to the Bulk Lifetime of Silicon Crystals for Power Device Application

Among the insulated‐gate bipolar transistors (IGBTs) and PIN junction diodes, there are devices that the recombination centers, namely lifetime‐control defects, are introduced into phosphorus (P) doped n‐type silicon (Si) crystals by electron beam irradiation. The lifetime‐control defects are considered as they form deep levels such as the vacancy–vacancy (V–V) pair and vacancy–phosphorus (V–P) pair. In the case of using Czochralski Si wafers, it is considered that some pairs of carbon (C), oxygen (O), and their complexes are believed to have a negative impact to the lifetime‐control defects. In this study, density functional theory (DFT) calculations are performed to understand the formation behavior of lifetime‐control defects and the formation behavior of complexes composed of C and O atoms believed to interact with lifetime‐control defects. On the basis of these results, DFT calculations related to the structural change of lifetime‐control defects are performed. The most important result is that instead of the interstitial carbon–substitutional carbon (Ci–Cs) pair, the interstitial Ci atom and interstitial carbon–interstitial oxygen (Ci–Oi) pair are the strong candidates to affect controllability of lifetime by interacting with V composed of lifetime‐control defects.

CHARACTERIZATION AND MODELING OF INTEGRATED DIODE IN 1.2kV 4H-SiC VERTICAL POWER MOSFET

We have characterized and modeled the integrated diode of a 1.2kV 4 H - SiC power MOSFET. We have measured its static and dynamic characteristics up to 200°C and extracted relevant SPICE model parameters. From the extracted turn-on voltage and ideality factors, we conclude that the integral diode is not a pin junction diode, but a unipolar diode.

Direct Conversion of High Energy Protons to Electricity Using a Solid-State Pin Junction Diode

Using a single junction PIN (p-type, intrinsic, n-type) diode, made of silicon, and doped with boron and phosphorus, high energy protons have been converted to electricity, through ionization from electronic stopping in the silicon, at an efficiency of 0.2%. A simulation of 3.02 MeV D-D protons has been performed, using a 3 MeV linear accelerator. Proton fluxes of ∼3x1010 protons·cm-2s-1 were incident on a PIN diode with 0.7 cm2 of surface area facing the incident protons. Losses in efficiency as a function of proton fluence are compared with dpa (displacements per atom) rates calculated using the Monte Carlo ion transport code TRIM (Transport and Ranges of Ions in Matter).

Thick and large area PIN diodes for hard X-ray astronomy

Thick and large area PIN diodes for the hard X-ray astronomy in the 10–60 keV range are developed. To cover this energy range in a room temperature and in a low background environment, Si PIN junction diodes of 2 mm in thickness with 2.5 cm 2 in effective area were developed, and will be used in the bottom of the Phoswich Hard X-ray Detector (HXD), on-board the ASTRO-E satellite. Problems related to a high purity Si and a thick depletion layer during our development and performance of the PIN diodes are presented in detail.

Electrical characterization of GaAs PiN junction diodes grown in trenches by atomic layer epitaxy

We report the electrical characterization of GaAs PiN junction diodes grown over the sidewalls of patterned trenches by atomic layer epitaxy. The diodes exhibit excellent rectifying behavior demonstrating that high quality GaAs was grown on the entire trench structure including sidewalls and corners. The sidewall material is characterized electrically through reverse bias diode leakage from thermal generation in the depletion region. 2-μm-deep trenches contribute a leakage current of less than 60 μA/cm2 of sidewall area under 1 V reverse bias at 144 °C, which is satisfactory for most device applications.

Computer Modeling of Batteries from Nonlinear Circuit Elements

Circuit analogs for a single battery cell have previously been composed of resistors, capacitors, and inductors. This work introduces a nonlinear circuit model for cell behavior. The circuit is configured around the PIN junction diode, whose charge‐storage behavior has features similar to those of electrochemical cells. A user‐friendly integrated circuit simulation computer program has reproduced a variety of complex cell responses including electrical isolation effects causing capacity loss, as well as potentiodynamic peaks and discharge phenomena hitherto thought to be thermodynamic in origin. However, in this work, they are shown to be simply due to spatial distribution of stored charge within a practical electrode.