Equivalent series resistance

About: Equivalent series resistance is a research topic. Over the lifetime, 5335 publications have been published within this topic receiving 83362 citations. The topic is also known as: ESR.

High‐efficiency (19%) screen‐printed textured cells on low‐resistivity float‐zone silicon with high sheet‐resistance emitters

Abstract: High-efficiency 4cm 2 screen-printed (SP) textured cells were fabricated on 100Ω/sq emitters using a rapid single-step belt furnace firing process. The high contact quality resulted in a low series resistance of 0.79 Ωcm 2 , high shunt resistance of48 836 Ωcm 2 , a low junction leakage current of 18·5 nA/cm 2 (n 2 = 2) yielding a high fill factor (FF) of 0·784 on 100 Ω/sq emitter. A low resistivity (0·6 Ωcm) FZ Si was used for the base to enhance the contribution of the high sheet-resistance emitter without appreciably sacrificing the bulk lifetime. This resulted in a 19% efficient (confirmed at NREL) SP 4cm 2 cell on textured FZ silicon with SP contacts and single-layer antireflection coating. This is apparently higher in performance than any other previously reported cell using standard screen-printing approaches (i.e., single-step firing and grid metallization). Detailed cell characterization and device modeling were performed to extract all the important device parameters of this 19% SP Si cell and provide guidelines for achieving 20% SP Si cells.

MEMS-based series and shunt variable capacitors for microwave and millimeter-wave frequencies

Abstract: This article describes design and modeling of MEMS-based variable capacitors with rf performance acceptable for microwave and millimeter-wave applications. Appropriately designed thermal actuators are used to move the MEMS capacitor plate vertically to change the air gap between the MEMS plate and the signal line of a coplanar waveguide (CPW). Both series- and shunt-mounted capacitors have been demonstrated. Effect of actuator design on rf performance is investigated by electromagnetic simulation. Experimental results show an air gap change resulting in a capacitance variation with a ratio of 2.7:1. For the shunt-mounted capacitor, the capacitance showed no self-resonance and the equivalent resistance is less than 0.5 Ω in the frequency range up to 40 GHz. The MEMS-based variable capacitors are described with an emphasis on rf design and characterization. In particular, the effects of actuator design on rf performance are discussed in details.

Reduction of Series Resistance in Organic Photovoltaic Using Low Sheet Resistance of ITO Electrode

Abstract: The series resistance of organic photovoltaic (OPV) devices was decreased by reducing the sheet resistance (R sh ) of the indium tin oxide (ITO) electrode, which leads to increasing device efficiency. The performance of bulk heterojunction OPVs was critically dependent on R sh of the ITO electrode. Upon reducing R sh of the ITO from 39 to 8.5 Ω/□, the fill factor and power conversion efficiency of OPV was improved (from 0.407 to 0.580 and from 1.63 ± 0.2 to 2.5 ± 0.1%, respectively) under an AM1.5 simulated solar intensity of 100 mW/cm 2 . The dependence of the series resistance on R sh of the ITO suggests the dominance of the bulk resistance of the ITO electrode as a limiting factor in practical cell efficiencies.

Comprehensive Study on Electrical and Hydrogen Gas Sensing Characteristics of Pt/ZnO Nanocrystalline Thin Film-Based Schottky Diodes Grown on n-Si Substrate Using RF Sputtering

Abstract: This paper presents a comprehensive study on the electrical characteristics of Pt/ZnO thin film Schottky contacts fabricated on n-Si substrates by RF sputtering, and its application as a Hydrogen sensor. The basic structural, surface morphological, and optical properties of the ZnO thin film were also been explored. Pt/ZnO thin film junction was characterized using current–voltage (I–V) and capacitance–voltage (C–V) measurements at room temperature, exhibiting rectifying behavior with barrier height, ideality factor and series resistance of 0.71 eV (I–V) /0.996 eV (C–V), 2.5 and ∼95 Ω respectively. The lack of congruence between the values of Schottky barrier heights calculated from I–V and C–V measurements is interpreted. Cheung's method and modified Norde's functions were employed along with the conventional thermionic emission model, to incorporate the impact of series resistance in the calculation of diode parameters. We unveiled, the Hydrogen sensing characteristics displayed by the Pt/ZnO thin film-based sensor to different concentrations (200–1000 ppm) of Hydrogen at 350 °C. The sensor has exhibited good recoverable transient characteristics under a series of Hydrogen exposure cycles with a maximum sensitivity of 57% at 1000 ppm of Hydrogen.

Supercapacitors Improve the Performance of Linear Power-Management Circuits: Unique new design options when capacitance jump from micro-farads to farads with a low equivalent series resistance

Abstract: For over a century, the electronics design community has used electrolytic or polypropylene capacitors with values from 10 pF to 100,000 nF, and they come with voltage ratings from less than 10 V to several thousand volts. They are traditionally used for filters, dc blocking, and very short-term energy storage in electronic circuits. Within the last two decades, a new form of capacitors, electric doublelayer capacitors (EDLCs), entered the electronic marketplace, filling the gap between rechargeable batteries and electrolytic capacitors. Today, these devices are generally known as supercapacitors (SCs), ultracapacitors (UCs), electrochemical capacitors (ECs), and EDLCs.