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Bulk lifetime studies of crystalline silicon wafers, e.g. with the aim of studying the light-induced degradation and regeneration behavior, require low-temperature surface passivation schemes that do not alter the silicon bulk properties, e.g. through hydrogenation. Aluminum oxide (Al2O3) can provide an excellent and stable surface passivation, however, in order to achieve the best possible surface passivation, an annealing step at ∼400°C is typically required, which has been found to alter the bulk properties of some silicon materials. Hence, in this contribution we examine the possibility of passivating the silicon surface using Al2O3 layers that have seen a much lower thermal budget. We demonstrate that we are able to achieve an excellent silicon surface passivation using atomic-layer-deposited Al2O3 with measured effective surface recombination velocities Seff as low as 1.3 cm/s without exceeding a temperature of 250°C. We are able to achieve such excellent low-temperature passivation by applying a post-deposition annealing step at 250°C in combination with the deposition of negative Corona charges on the Al2O3 surface. For samples annealed at only 220°C, we still reach very low Seff values of 2 cm/s after deposition of negative Corona charges. We demonstrate that the Corona-charged low-temperature Al2O3 passivation shows only a slight degradation from an Seff of 1.6 cm/s to an Seff of 5 cm/s after 218 days of storage. Even without any post-deposition anneal and only negative Corona charges deposited, we achieve stable Seff values of 15 cm/s. As an alternative to Corona charging, a short exposure to intense UV light (λ = 395 nm) also significantly improves the surface passivation quality of low-temperature-annealed Al2O3-passivated silicon samples. However, the best surface passivation for the latter method is limited to an Seff value of 6.6 cm/s, which is still quite reasonable for bulk lifetime studies.

An interfacial regularized Stokeslet scheme is presented to predict the motion of solid bodies (e.g. proteins or gel-phase domains) embedded within flowing lipid bilayer membranes. The approach provides a numerical route to calculate velocities and angular velocities in complex flow fields that are not amenable to simple Fax\'en-like approximations. Additionally, when applied to shearing motions, the calculations yield predictions for the effective surface viscosity of dilute rigid body-laden membranes. In the case of cylindrical proteins, effective viscosity calculations are compared to two prior analytical predictions from the literature. Effective viscosity predictions for a dilute suspension of rod-shaped objects in the membrane are also presented.

Measurements of the dependence of the effective surface recombination velocity Seff at the Si‐SiO2 interface on light‐induced carrier concentration are presented. Contactless lifetime measurements by modulated free‐carrier IR absorption with additional bias light and by photoconductance decay measurements of samples immersed in HF were used to extract Seff for varying illumination levels. For various dopant concentrations the measured surface recombination velocities are compared with theoretical predictions calculated using an extended Shockley–Read–Hall formalism for Si‐SiO2 interfaces. Good agreement was obtained. The consequences for solar cell performance and lifetime measurement techniques are discussed.

The surface Debye temperature of the NiMnSb (100) epitaxial films has been obtained using low energy electron diffraction, inverse photoemission, and core-level photoemission. The normal dynamic motion of the (100) surface results in a value for the effective surface Debye temperature of 145±13 K. This is far smaller than the bulk Debye temperature of 312±5 K obtained from wave vector dependent inelastic neutron scattering. The large difference between these measures of surface and bulk dynamic motion indicates a soft and compositionally different (100) surface.

This project has been supported by the Australian Government through the Australian Solar Institute, part of the Clean Energy Initiative.

A micropump based on a pair of liquid marbles coated with various powders and connected with a capillary tube is presented. The idea of the micropump is based on the difference of the Laplace pressures in the marbles. The initial stream was supported by the pressure instability developed under water overflow. The reported experiments validate the concept of the effective surface tension of liquid marbles. The micropump could be used for precise delivery of small quantities of liquids, the design of microreactors and microfluidics applications.

The measurement equations for the capacitive probe, dissectable capacitor, and vibrating capacitor methods of determining the effective or apparent surface charge density on a dielectric are derived as special cases of a single theory. The results agree with those of other authors.

The effects of dose, implantation temperatures, and annealing on the electrical properties of Zn‐implanted GaAs0.62P0.38 were measured. Zinc ion implantation was performed with 20‐keV ions at temperatures between room temperature and 450 °C. The abnormal property that the effective surface concentration exceeds the implanted Zn dose was obtained for the samples implanted at room temperature.

High-low (HL) junctions form a part of many semiconductor devices, including back surface field solar cells. A first experimental determination and interpretation of the voltage across the HL junction under low- and high-injection conditions is presented as a function of the voltage across a nearby p/n junction. Theoretical analysis from first principles is shown to bear well on the experimental results. In addition, a test structure is proposed for measurement of the effective surface recombination velocity at the HL junctions.

Measurements of capacitance, dc surface conductance, and photoconductivity vs fieldplate voltage on metal‐insulator‐semiconductor (MIS) structures on 0.09‐eV bandgap HgCdTe are reported. Surface‐state density, effective surface charge, and field‐effect mobilities for electrons and holes are obtained and discussed. Below 100°K the electron field‐effect mobility is relatively high, and the field‐effect mobility ratio is comparable to the mobility ratio in bulk material.

The results of thermally stimulated depolarization current and effective surface charge‐density measurements indicate that magnetic fields do not produce carnauba wax electrets and that previously reported data can be attributed to nonmagnetic effects.

A rotating probe assembly suitable for effective surface‐charge decay‐rate measurements is described. Utilizing computer acquistion of data, low resolution charge distribution measurements can be made.