Current Paths over Grain Boundaries in Polycrystalline Silicon Films

Abstract

An optoelectronic system is described for making quasi-simultaneous recordings of muscle transparency at orthogonal beam polarisations. A Pockels cell is used to oscillate the €-vector of a laser beam ( j . = 632.8, 514.5, 488 and 457.9 nm) through n12 radians (at 7.4 kHz), between 0 and 90 relative to the muscle long axis. The intensity of light transmitted by the muscle is detected using a photomultiplier tube. The photomultiplier output is fed to a sample-hold device which generates two analogue signals, each of which records the transmitted intensity at one of the two incident €-vector orientations. The data are captured using a dual-channel transient recorder and are stored on floppy discs. The ability of the system to make time-resolved (millisecond scale) measurements of muscle conservative dichroism is illustrated with recordings made during 'ramp' stretches applied to fully activated frog muscles.

Electric Current-Induced Liquation Features of Cast Pure Tin

“…On the other hand, an electric current may traverse grain boundary in a less-cross-section-area, more perpendicularpath manner to ensure that an electric current passes through the lower electrical-resistivity paths as possible as it can. These results are also consistent with the analysis by Kimura et al 3) which concluded that the current tends to flow over grain boundary perpendicularly and avoid passing through grain boundary triple junction. Since the two grain boundaries through which a fusion path crosses to adjacent grains are usually nonparallel, geometrical constraint of normal intersection requires the fusion path to be curved inside the grain.…”

“…In a two-dimensional simulation of silicon thin film taking grain boundaries as the trapping site of charge carriers, Kimura et al 3) have concluded that the current density is the highest in the center region of a grain. This phenomenon of non-uniform current distribution is more pronounced when the grain size is getting smaller (Fig.…”

Analysis of Hall Voltage in Micro Poly-Si Hall Cells

“…Here, I flows through zigzag paths to avoid the high potential barriers at the triple points of the grain boundaries. 22,23 In other words, V H has an offset voltage because the Hall terminals are not electrically located just at the center of the zigzag paths, although they are spatially located just at the center of the current terminals. For example, the maximum offset voltage of 590 V in cell A corresponds to the difference between the electrical and structural centers of 240 nm because L = 40 m and V = 0.1 V. Therefore, the offset voltage is mainly caused not by the pattern variation but by the zigzag path.…”

Extraction of Trap States at the Oxide-Silicon Interface and Grain Boundary for Polycrystalline Silicon Thin-Film Transistors

“…The first assumption is that current paths flow perpendicular to the grain boundaries, and the validity has been confirmed elsewhere. 63) The second assumption is that the number of grain boundaries in a device can be known, and it can be determined as follows. The average grain size is observed using techniques such as scanning electron microscopy and tunneling electron microscopy, and the average number of grain boundaries is acquired.…”