Series resistance structure

The ohmic series resistance is determined by the geometrical layout of the capacitor as well as by the conductance of its electrodes. The electrochemically etched array of straight pores produces a comb-like electrode structure and gives very low values of electrical series resistance (ESR) for the capacitor chip. 

We report here plasma etch rate data for a series of vinyl resist polymers with a wide range of side chain substituents. The results of this study are valuable because they provide, when combined with other radiation chemical test data. Improved design criteria for making improved high performance radiation resists. Structural fomulae and chemical nomenclature plus acronyms for the vinyl polymer systems studied are compiled below ... 

Fig. 26. Characteristic I-U curves of S-NDR systems (a) under potential control for vanishing ohmic series resistance, Rq (b) under potential control for intermediate values of Rq. The dashed vertical lines indicate that S-NDR systems might oscillate in an intermediate interval of U, but corresponding parameter values are very unlikely such that in general an experimental cyclic voltammogram will look like the solid curve (c) under current control, where the sandwiched branch is unstable with respect to spatial variations and an I/U measurement exhibits a hysteresis, as indicated by the arrows. The middle, thick curve corresponds to a spatially structured state (see Section 4.2.2).

The aperture area of a solar module is defined by the inner boundary of total laser scribed area. For every kind of series-connection, the active solar cell area is reduced by the area of the interconnection structure. Area losses increase if the cell width is reduced. On the other hand, electrical losses in contact layers become more severe with increasing cell width due to increasing cell current. Hence, optimization of the cell width must consider both area losses (dead area) due to patterning and series resistance losses due to TCO sheet resistance. These power losses can be described by the loss factors /, which is the sum of the loss factors /d (area losses) and /tco (resistive losses in front TCO) [69] ... 

A major degradation mechanism of modules is the decrease in fill factor. This is caused by an increase in the diode quality factor of the cells making up the module and by an increase in series resistance. The former is related more to the absorber and heterojunction properties and less to the ZnO properties. The series resistance increases because the conductivity of the ZnO drops and because the interconnects are deteriorating. Wennerberg et al. have assessed the individual contributions to increased series resistance [50]. Klaer et al. [52,53] have described a transmission-line test structure that allows to separate the contributions of contact and sheet resistance, respectively. The test structure is prepared by the same scribing techniques as those used in module manufacturing. 

The other approach to valve noise problems is the use of quiet trim. Two basic strategies are used to reduce the initial production of noise—dividing the flow stream into multiple paths and using several flow resistances in series. Sound pressure level Lp is proportional to mass flow and is dependent on vena contracta velocity. If each path is an independent source, it is easy to show from Eq. (8-120) that p is inversely proportional to the number of passages additionally, smaller passage size shifts the predominate spectral content to higher frequencies, where structural resonance may be less of a problem. Series resistances or multiple stages can reduce maximum velocity and/or... 

Figures 4 and 5 show typical I-V curves and electroluminescence spectra collected by ARL for 280nm UV LEDs. Analysis of the 1-V curve for the 280nm UV LED gives a series resistance of only 9D, indicating excellent electrical properties of the n- and p-type layers of this structure. An optical power output of 0.6 mW was obtained at 20mA and an operating voltage of 5.39V. This gives a wall-plug efficiency of 0.56% for this...

Recently, Cree Research Inc. reported on the first p-channel 6H-SiC MOSFET [6]. The device structure and output characteristics are shown in FIGURES 8 and 9, respectively. The device current and transconductance are very small (76 pA mm 1 at 40 V of drain bias and 16 pS mm 1, respectively, for a 7 pm gate length device). The performance of this device was limited by a large parasitic series resistance. Nevertheless, even these preliminary results show the feasibility of SiC CMOS technology, capable of operating at elevated temperatures. 

Contact resistance (Rc) includes all series resistance that does not scale with channel length. Contact resistance will include resistance attributable to the source and drain composition, the interface between the semiconductor and the contacts, and edge induced morphological or other structural changes which change the channel resistance but do not operate in the center of the channel. 

Figure 8.12a and b shows the frequency dispersion in the C-V characteristics of MOS capacitor structure after series resistance correction. The frequency dispersion at accumulation is mainly due to the presence of interface traps at the semiconductor insulator contact region. The capacitance of such a layer acts in series with the insulator capacitance causing frequency dispersion. However, negligible frequency dispersion is observed in the inversion region. 

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