Grain-size distribution and texture

Microstructure Design in Thin Metallic Films 6.2.1. Grain-size distribution and texture 

Application of the LIMET method to amorphous or nanocrystalline thin films can lead to changes in their structural properties. The films are molten during the exposure to a laser pulse with intensity above a certain threshold, and solidify again so that crystallization or recrystaUi2ation occurs at the local and periodic heated zones. 

Changes in the film microstructure (e.g. texture and grain-size distribution) of the laser-treated Pt thin films were analyzed using Electron Backscatter Diffraction (EBSD). The determination of the orientation of the crystal ensemble and the grain-size distribution has been performed on the cross-like pattern showed in Fig. 9(c). 

Texture analysis on the cross-like pattern reveals a (111) direction, parallel to the normal of the sample (see pole figure in Figs. 9(a), 9(b), and 9(d)). Two domains were differentiated to perform the texture analysis. In Figs. 14(a) and 14(b), the two analyzed domains of both parts of one interference maximum are shown (see Fig. 9(c)). Analyzing these two domains separately leads to completely different texture as shown in Figs. 9(a) and 9(b). However, the texmre analysis of the overlapped area of two interference maxima (see interrupted line in Fig. 9(c)), presents afiber texture (see Fig. 9(d)). 

The determination of mechanical properties of periodically re-crystallized Pt thin films has been performed using a nanoindentation test. The sample surface was subjected to a loading — unloading cycle with a Berkovich diamond tip. Using the calculation method developed by Oliver and Pharr,local measurements of both hardness H) and Young modulus E) of the thin Pt films have been carried out. 

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It is seen from the discussion above that Cu is electrodeposited in vias and trenches on a bilayer a barrier metaVCu seed layer. When the barrier layer is composed of two layers (e.g., TiN/Ti), Cu is electrodeposited as a trilayer a barrier bilayer/Cu seed layer. This type of underlayer for electrodeposition of Cu raises a series of interesting theoretical and practical questions of considerable significance regarding the reliability of interconnects on chips. In Section 19.1 we have noted that interconnect reliability depends on the microstructural attributes of electrodeposited Cu (for Cu-based interconnects). These microstractural attributes, such as grain size, grain size distribution, and texture, determine the mechanical and physical properties of the thin films. Thus, one basic question in the foregoing series of questions is the problem of the influence of the underlayer barrier metal on the microstructure of the Cu seed layer. The second question is the influence of the microstructure of the Cu seed layer on the structure... 

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