Properties Of Silicon Layers Research Articles

Nano-Indentation for Measurement on Mechanical Property of Building Integrated Amorphous Silicon Thin-Film PV Cell

Amorphous silicon thin-film PV cell(AST) generally consists of a few – micron thick silicon film on a glass substrate, which has difficulty for being accurately measured by using a conventional testing method to obtain its elastic modulus and hardness. In our study, we are applying nanoindentation for the measurement purpose and divide the sample into five regions for studying. Both of peak load - and loading rate - dependences supervise us to more accurately measure the mechanical properties of silicon layer through defining the peak load at 9000μN and loading rate at 1000μN/s. It was also observed that across the whole sample measurements on the elastic modulus have much better consistence than those on the hardness. We therefore propose a method of partitioning the sample into two parts for counting the different hardness measurements.

Luminescent and Structural Properties of Self-Implanted Silicon Layers in Relation to their Fabrication Conditions

Luminescent and structural properties of silicon layers with dislocation-related luminescence have been studied. Silicon ions (100 keV) were implanted into n-FZ-Si wafers at a dose exceeding the amorphization threshold by two orders of magnitude. The implantation was not followed by amorphization of the implanted layers. A post-implantation annealing resulted in the formation of luminescence centers and extended structural defects. Some fundamental aspects and specific features in the properties of dislocation-related luminescence lines and extended structural defects were revealed in relation to the annealing conditions.

Electrical properties of silicon layers implanted with erbium and oxygen ions in a wide dose range and thermally treated in different temperature conditions

The electrical properties of silicon implanted with Er and O ions in a wide dose range have been studied. The dependence of electron mobility on the concentration of electrically active centers is determined for Si:Er layers with Er concentrations in the range of 9×1015–8×1016 cm−3. Sharp bends related to specific features of Er segregation in solid-phase epitaxial recrystallization are observed in the concentration profiles of electrically active centers, n(x), and Er atoms, C(x), at Er ion implantation doses exceeding the amorphization threshold. The n(x) and C(x) profiles virtually coincide near the surface. A linear rise in the maximum concentration of electrically active centers at approximately constant effective coefficient of their activation, k, is observed at Er implantation doses exceeding the amorphization threshold. At an Er concentration higher than 7×1019 cm−3, the concentration of electrically active centers levels off and k decreases.

Electrical properties of silicon layers implanted with ytterbium ions

It is ascertained that implantation of 1-MeV ytterbium ions with a dose of 1013 cm−2 into silicon with subsequent annealing at temperatures of 600–1100°C gives rise to donor centers. The donor-center concentration is higher in the samples implanted additionally with oxygen ions. The results show that at least two types of donor centers are formed; these centers contain either ytterbium or oxygen impurity atoms. The dependence of electron mobility on the concentration of electrically active centers in the silicon layers implanted with the ytterbium rare-earth ions is determined in the concentration range of 7×1015–1017 cm−3.

Ionization-enhanced crystallization of phosphorus implanted silicon layers

Abstract The influence of ionization density on the annealing properties of silicon layers implanted with 1.2 × 1014-l × 1015 cm−2 of phosphourus ions has been studied. The ionization background was created by high energy electrons from a Van de Graaff accelerator with the beam density on a sample in the range of 2.5–25 μA/cm 2. The dependence of the crystallization growth rate vg on the e-h recombination rate has been observed. An exponential dependence of the growth rate vg on the ionization density was observed for amorphized and nonamorphized Si layers. No change of the activation energy Ea . in the used beam density range was noticed.