Substrate misorientation

The pore growth direction is along the (100) direction and toward the source of holes. For the growth of perfect macropores perpendicular to the electrode surface (100), oriented Si substrates are required. Tilted pore arrays can be etched on substrates with a certain misorientation to the (100) plane. Misorientation, however, enhances the tendency to branching and angles of about 20° appear to be an upper limit for unbranched pores. For more details see Section 9.3. 

The structure of films of zirconia-based solid electrolytes was analyzed in a scanning electron microscope. It was found that both one- and multilayer films (Fig. la, lb) of zirconia, which was stabilized to its cubic modification, up to 10 pm thick had a columnar structure, that is, consisted of mutually adjoining crystallites, which generally were oriented perpendicularly to the film surface. The observed deviation of the crystallites from the normal direction to the film plane was not over 15° and was explained by the mutual misorientation of the target and the substrate. 

Figure 7.6. Dependence of the surface morphology of diamond films on the off-angle (misorientation angle) of the (100) substrate and the CH4 concentration. Diamond films were grown at Ts = 815 and 1200°C [109].

Figures 12.9 (a) and (b) are the XPF spectra from a (11 l)-oriented diamond film grown for 30h on single crystal Pt(lll) (see Figure 12.7 (a)) and a Pt(lll) substrate, respectively [383, 394]. The FWHM of diamond 111 diffraction poles was approximately 4°. This value was similar to the FWHM of highly (100)-oriented diamond films on silicon, i.e. 5°. However, since the FWHM value includes diffraction signals from misoriented diamond particles near the Pt interface, the 4° FWHM should be the upper limit of the misorientation distribution. Note that...

Microcrystalline fabric (Figure 7.6C), not to be confused with the randomly orientated crystals of carbonate mud-micrite textures, has been discriminated from columnar fabric on the basis of the irregular stacking of crystallites and the high density of crystal defects. It has been observed in annually laminated alpine stalagmites, where it forms milky, opaque and porous layers. The misorientation of some crystallites with respect to their substrate yields composite crystals with serrated to interfingered... 

Many TEM studies show that the GB films grown by physical vapor deposition (PVD) on bicrystal substrates are wavy and the typical facet size is about 50 nm [4.35-4.37]. Therefore, the dependence of critical current density on misorientation angle is difficult to study with these films. Recently, liquid-phase epitaxy (LPE) was successfully used to obtain large single-facet grain boundaries. Fig. 4.20 shows a plan-view image of the GB of a YBCO film grown on a 24° MgO bicrystal. It clearly shows that the GB is a symmetrical... 

Fig. 10.1. Critical current densities Jc for grain boundaries in YBCO films grown by epitaxy on suitably treated single crystal or bicrystal substrates, plotted against the [001] misorientation angle [10.4, 10.7, 10.51, 10.59, 10.60].

Fig. 14.2. Critical current density as a function of misorientation angle of [001]-tilt YBCO boundaries on SrTiOs bi-crystal substrates. Data are extracted from [14.1-14.4].

Figure 1. Schematic arrangement of Ga and As atoms on a (111)A surface with a misorientation of the substrate respect to the [211] direction (a), and schematic view of the Hall bridge for measurements of resistance anisotropy (b).

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