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50 PCB007 MAGAZINE I JUNE 2018 tion. Lotgering factor needs to be considered to verify this. The Lotgering factor, f, is for each Miller index (hkl) showing whether it is in the range of the thermodynamic stable Miller in- dex distribution for copper (literature values) or which crystal orientation is more preferred up to a certain degree [10] . The calculation of the Lotgering factor for each Miller index is per- formed according to the following equation (here for the example (00l): Eq. 3 where P 00l is the sum of the relative inten- sities for all (00l) diffractions divided by the sum of the intensities of all (hkl) diffractions (Σ I 00l / Σ I hkl ), and P O is similarly defined for a randomly oriented sample (Σ I 0 00l / Σ I 0 hkl ). The maximum obtainable value for the Lotgering factor is 1. This means that there is a very high preference for this Miller index. Table 4 shows the positive values for (111) plane, indicating that the deposits have a slight preference for (111) plane over others, which is the densest plane of all. The hardness of the copper foils is indepen- dent from the bath age at 79 ± 8 HV 0.05 . Fur- thermore, up to 150 Ah/L the incorporation of carbon, sulfur, nitrogen and chloride into the copper lattices was investigated. The results are shown in Table 6. Impurity analysis was done as follows: C and S using combustion IR method using production analysis equipment, N by using carrier gas hot extraction (CGHE) Figure 10: X-ray diffraction pattern for copper deposit plated using current formula. Eq. 2 Table 2: X-ray diffraction data of the deposit at different bath age. Tabulated in Table 3 is the crystal size cal- culated from the full width at half maximum (FWHM) from the XRD peaks using the Scher- rer equation (Eq.2). The data show no sub- stantial changes in the crystal size, which agrees with the FIB images in Table 5, showing the grain structure of the plated copper at dif- ferent bath age. Beside the relative intensities of the crystal orientations, the crystallograph- ic density and the lattice constant is also of interest whether there is a preferred orienta-

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