Supplementary MaterialsSupplemental Material TSTA_A_1536679_SM7424. three-stage co-evaporated CIGS slim films. Passivation from
Supplementary MaterialsSupplemental Material TSTA_A_1536679_SM7424. three-stage co-evaporated CIGS slim films. Passivation from the voids internal surface area may reduce their detrimental results. at room temp. SEM cross areas indicate that bigger, well described grains are shaped when the CIGS film converts from Cu-poor (Test 1) to Cu-rich (Test 2). That is in keeping with the recrystallization process observed following the first stoichiometry point  typically. The grain size and consistency of Test 2 act like those typically noticed for finished CIGS growths (e.g. in research ). Two prominent XRD peaks are found for both examples at ~?27 and ~?28, related towards the anticipated positions from the (112) and (103) reflections from the CIGS alpha-phase. The XRD design of Test 1 Maraviroc cost exhibits an additional little peak at ~?25 and a big shoulder between your 112 and 103 peaks. Both of these features have already been referred to as the Maraviroc cost personal for a big denseness of stacking faults in CIGS movies that didn’t go through a Cu-rich stage . These features aren’t visible in Test 2. That is in keeping with the re-crystallization from the CIGS film and annihilation of stacking faults in the Cu-poor to Cu-rich changeover in low-T multi-stage deposition without alkali components [15,23,25]. Shape 1. Selected parts of XRD patterns of Examples 1 (development interrupted prior to the 1st stoichiometry stage) and 2 (development interrupted soon after the very first stoichiometry stage) with related cross-sectional SEM micrographs. XRF measurements indicate that both examples have nearly stoichiometric or stoichiometric Cu amounts (CGI 0.98??0.02 for Sample 1 and 1.00??0.02 for Sample 2). It is not surprising that Sample 2 exhibits Cu-Se phase segregation despite the stoichiometric Cu concentration. Phase diagrams indicate in fact that Cu-Se phases may segregate already at CGIs above 0.95 . 3.2. Evolution of the compositional distribution and grading A HAADF-STEM micrograph and STEM/EDX compositional mappings of Sample 1 are demonstrated in Shape 2. Cu can be distributed over the specimen homogeneously, aside from the particular region encircling from the opening in the right-hand part from the specimen, where some variants from the Cu focus are because of the specimen planning, which may bring about Cu migration in the certain specific Maraviroc cost areas from the specimen closest towards the unprotected edges. Also, CGI maps indicate a homogeneous Cu distribution in the lateral path. GGI maps display the anticipated GGI grading over the thickness from the film up to the low-GGI area at the front end (top of the image). The intentional GGI grading observed by STEM/EDX across the sample thickness was confirmed by SIMS depth profiling (not shown). Maraviroc cost This is consistent with the interruption of the deposition before the Cu-rich stage. The sample presents some randomly distributed GGI inhomogeneities. The lateral variations of the GGI values are 0.10-0.15. The inhomogeneous areas have granular shapes and diameters of 100C200?nm. Figure 2. Sample 1: STEM-HAADF (top left), EDX Cu at.% map (top-right), GGI map (bottom-left) and CGI map (bottom-right). Figure 3 shows HAADF-STEM micrographs and STEM/EDX compositional mapping of Sample 2. Cu-Se phases accumulate at grain boundaries and at crevices between CIGS grains, as shown by the Cu at.% and CGI maps. Very similar patterns have been observed in all other analyzed sections of the same specimen (Figure 3 supp.). The Cu-Se filled openings can reach sizes of Maraviroc cost to many a huge selection of nanometers up. These locations can be found in general, however, not solely, at the top of Cu-rich CIGS film. In and Ga aren’t within the crevice areas (helping information Body 4 supp.). The current presence of small voids may also be seen in the HAADF-STEM micrograph in correspondence of Cu-Se segregation squares in Body 3 (one void region continues to be enlarged for better watch). Body 3. Test 2: STEM-HAADF (best left), EDX Cu at.% map (top-right), GGI map (bottom-left), and CGI map (bottom-right). The GGI map of Sample 2 shows laterally uniform Ga to In ratios in the lower half TMEM8 of the film. In the upper half of the film some regions can be observed where the GGI values are laterally inhomogeneous, with widths of 100C200?nm and average GGI variations of approximately 0.05C0.10. Higher GGI values can be observed only in the regions surrounding those where.