Van der Pauw method

About: Van der Pauw method is a research topic. Over the lifetime, 1682 publications have been published within this topic receiving 25364 citations.

Rapid thermal and pulsed laser annealing of boron fluoride‐implanted silicon

Abstract: Characteristics of rapid thermal and pulsed laser annealing have been investigated in boron fluoride‐ (BF+2 and BF+3) ‐implanted silicon using cross‐section and plan‐view electron microscopy. The amorphous layers recrystallize by the solid‐phase‐epitaxial growth process, while the dislocation loops below the amorphous layers coarsen and evolve into a network of dislocations. The dislocations in this band getter fluorine and fluorine bubbles associated with dislocations are frequently observed. The secondary‐ion mass spectrometry techniques were used to study concomitant boron and fluorine redistributions. The as‐implanted Gaussian boron profile broadens as a function of time and temperature of annealing. However, the fluorine concentration peak is observed to be associated with dislocation band, and the peak grows with increasing time and temperature of annealing. The electrical properties were investigated using van der Pauw measurements. The electrical activation of better than 90% and good Hall mobilit...

Ca-substituted, A-site deficient perovskite La0.2Sr0.7TiO3 as a potential anode material for SOFCs

Abstract: Samples from across the solid solution series La0.2Sr0.7−xCaxTiO3, were successfully synthesised by solid state reaction. Structural properties were determined at room temperature using X-ray powder diffraction and conductivity measurements were performed using the four probe DC and van der Pauw techniques at different temperatures and atmospheres. On increasing x, the perovskite phase lattice symmetry changes from cubic Pmm to tetragonal I4/mcm at x = 0.05 and tetragonal to orthorhombic Pbnm at x = 0.425. The lattice also shrinks as x increases. Samples showed only a slight 0.3% increase in lattice volume after reduction at 900 °C in 5% H2. On increasing calcium doping, conductivity in reduced samples and equilibrated at 900 °C in 5%H2 increased markedly reaching 27.53 S cm−1 at x = 0.45, but decreased as x increased further.

Effects of aluminum content and substrate temperature on the structural and electrical properties of aluminum-doped ZnO films prepared by ultrasonic spray pyrolysis

Abstract: Transparent conductive aluminum-doped zinc oxide (AZO) films were prepared by an ultrasonic spray pyrolysis method. A vertical type hot wall furnace was used as a reactor in the deposition system Zinc acetate dissolved in methanol was selected as a precursor. The substrate temperature was varied from 180 °C to 240 °C. Aluminum (Al) was doped into ZnO films by incorporating anhydrous aluminum chloride AlCl3 in the zinc acetate CH3CO2)2Zn solution. The proportion of the Al in the starting solution was varied from 0 wt % to 3.0 wt %. The crystallographic properties and surface morphologies of the films were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The resistivity of the films was measured by the Van der Pauw method, and the mobility and carrier concentration were obtained through Hall effect measurements. Transmittance was measured in the visible region. The effects of substrate temperature and aluminum content in the starting solution on the structural and electrical properties of the AZO films are discussed.