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Figure 1: Solar cell efficiency distribution of a mc-Si ingot (wafer number increases from bottom to top).
Yet if one has to deal with very large areas (a standard mc-Si wafer is 156mm x 156 mm) and large number of samples the traditional technique is clearly inadequate.
In the image of the etched wafer, on the other hand, grain structure is less visible.
Long and thin structures like general grain boundaries possess large elongation factor.
We developed an etching recipe, and an image capture and processing algorithm to deal with large sample sizes and numbers.

The scanning electron microscope images of the films formed at 473 K showed the leaf like structure with grain size of 1.2 μm.
When substrate temperature increased to 573 K the size of the grains enhanced to 2.4 μm.
As a result, a large number of nuclei formed which coalescence at higher temperatures to form uniform films.
The films deposited at 473 K showed the leaf like grain structure with the area of the grain size of about 1.5 x 1 μm2.
Scanning electron micrographs of the films exhibited the leaf like grain structure and the size of the grains increased with the increase of substrate temperature.

Gd3+ doping has shown a significant effect on the grain growth.
To improve the electrical and piezoelectric properties of the material, a number of BNT based solid solutions and a number of processing methods have been studied extensively [5].
It shows that Gd doping causes a significant change in the grain size.
Gd3+ doping has shown a significant effect on the grain growth.
Kimura, Effect of Potassium Concentration on the Grain Orientation in Bismuth Sodium Potassium Titanate, J.

After remelting, YSZ also have no phase transformation, but the grain of the preferential growth orientation changed.
The substrate grain size is within 10 to 30 μm after spraying, and it is the same as the original substrate, grain size basically remains stable.
But grain size significantly grown larger after remelting, distribution in the range of 20 to 50 μm.
From the above analysis, oxygen diffusion channels increase by the change of substrate grain size after remelting.
After oxidation for 100 h, the number of diffraction peak of m phase increased, diffraction peak above 70° of t' phase almost disappeared.

Although the concentrations of Pb and Cd in grains were lower than other organs, Pb and Cd concentrations of grains under higher heavy-metal treatments exceeded the national guidance limit for three varieties of maize, suggesting heavy metal pollution may pose risks to human health.
The total number of subplots in the experiment was 15 (i.e. 5 heavy metal treatments × 3 varieties of maize).
In addition, the Pb concentration of the roots was higher than other parts, and the grain was the lowest (Table 3).
In higher Cd treatment, the concentrations of Cd decreased in the order tassels > roots > leaves > stalks > grains in variety A, whereas the order was roots > tassels > stalks > leaves > grains in variety B, and roots > tassels > leaves > stalks > grains in variety C (Table 3).
In lower Cd treatment, the concentrations of Cd decreased in the order roots > stalks > tassels > leaves > grains in all three varieties (Table 3).

However, the size of these zones and the sub-structure and orientations within them are important for predicting the number and orientations of nuclei around the particles.
The number of microstructural parameters and related descriptors that are important to track is high.
Structure Grain structure Constit.
Structure Grain structure Constit.
Halving the grain size to 50 µm has an even smaller effect.

In the area of interest about 200 grains were checked by SEM regarding the appearance of persistent slip bands (PSBs).
After both half cycle as well as full cycle loadings, the area of interest was scanned in the SEM searching grains with newly formed slip steps.
Table 1: Equations for calculation of the local slips during full cycle and the irreversible plastic slip in accordance to Fig. 2 Thickness of active areas within PSB Local slip variation during full cycle Irreversible plastic slip Case 0 Case A Thickness Dfc Thickness Dhc-Dfc Case B Thickness Dirrev Thickness Dhc-Dirrev Case C Thickness Dirrev Thickness Dfc Table 2: Summary of results from AFM measurements Half cycle loading Full cycle loading Preferred side of PSB for active slip (number of grains) Side A (obtuse angle) Side B (acute angle) 4 12 4 20 Investigated grains by AFM 12 (out of 16) 24 (out of 34) Slip irreversibility (number of grains) Complete reversibility (case 0) Complete reversibility + additional fc step (case A) Partial reversibility (case B) Complete irreversibility (case C) 2 6 3 1 Mean PSB slip variation (averaged on 12 grains and 24 grains, respectively) 3.4 % 3.8 % Mean PSB irreversible slip of PSBs
(averaged on 12 grains) 3.1 % Slip Irreversibility factor 0.8 The calculated mean slip variations occurring either during half cycle or full cycle loading are very close, which means that the limited number of studied grains and PSBs should nevertheless give meaningful results.

The nanoparticles has the role of crystalline grain refinement and better nucleation.
In the codeposition process, the highly active surface of nano-particles provide a large number of the deposition cores.
So, the coating is fine grain reinforcing. (2) Hard particle dispersion reinforcing.
It is known from Fig.3b that a small number of white phases are a little larger, it is due to agglomeration of some nano-particles.
The coatings are fine grain, smooth surface, uniform and dense of tissue.

Grain size distribution.
In Fig. 6, white bars exhibit the number fractions of all the grains, while black bars exhibit those of the grains within 15° from (0001) orientation.
The grain size decreases after deformation, and about half of grains smaller than 20μm has (0001) orientation.
All the grains greater than 70μm are (0001) grains.
Moreover, mean grain size of (0001) is larger than other grains.

EBSD analysis allows for the determination of microstructural parameters at a refined scale including grain size, grain misorientation, crystallographic and morphologic texture, and phase ratios, which can be employed to establish a correlation between microstructural changes and deformation mechanisms with temperature.
Mappings were post-processed via the spherical indexing process, which yields high-quality indexation (with a reduced number of points exhibiting a Confidence Index of less than 0.1), even at high strain levels.
However, it remains difficult to clearly predict the hierarchy of the different deformation mechanisms, which is strongly dependent of the microstructure (texture, grain size, phases…) and the temperature.
The processing workflow included re-indexing (combining spherical and neighbour pattern averaging indexing), followed by two clean-up steps (grain dilation and Confidence Index (CI) standardization).
This approach enabled high-quality EBSD maps, significantly reducing the number of points with CI values below 0.1, even at high strain levels [9].