Shadowing effects on the microstructure of obliquely deposited films

Abstract

Two spatial dimension front tracking simulations have been performed to study the growth of polycrystalline, faceted films from randomly oriented nuclei by varying the deposition angle of the incident flux during physical vapor deposition. The orientation of grain columns, the porosity, the crystallographic texture, and grain size are sensitive to the deposition angle. The origin of this effect is widely believed to be associated with shadowing. In order to isolate the effects of shadowing from other physical effects ͑such as surface diffusion, deposition species size, flux divergence, etc.͒, we have constructed a simulation where all of these effects are completely removed. These simulations demonstrate that while many of the observed structural properties of obliquely deposited films are controlled by shadowing, a few key properties cannot be attributed solely to shadowing.

On the relevance of large scale pulsed-laser deposition: Evidence of structural heterogeneities in ZnO thin films

“…An empirical relationship between the incidence angle a and the inclination of texture b "tg a ¼ 2 tg b" has been previously reported for films grown by various methods. [33][34][35] The reverse situation is observed here. The position of the maximum of the main peak in Fig.…”

“…Generally, under oblique angle deposition at RT by thermal evaporation or sputtering, the film texture is inclined towards the incident species direction, due to the shadowing effect and limited atom diffusion. [33][34][35] For the films grown by PLD at RT, we always observe an inclination of the c-axis in the forward direction, i.e., the reverse of the shadowing effect.…”

“…This is the reverse of the orientation classically reported in the case of the shadowing effect associated with oblique incidence deposition films. [33][34][35] Actually, under an oblique angle deposition a at room temperature (low adatom mobility), due to the self-shadowing effect, a columnar growth is observed inclined towards the incoming flux of species. An empirical relationship between the incidence angle a and the inclination of texture b "tg a ¼ 2 tg b" has been previously reported for films grown by various methods.…”

Size and shape dependence study of magnetization reversal in magnetic antidot lattice arrays

“…This angle leads to shadow effect during deposition and finally produces an in-plane magnetic anisotropy. It has been already shown by other groups that such shadow deposition usually leads to a uniaxial anisotropy [25,26]. A post-deposition lift off with acetone was performed on the prepared films to prepare the MAL arrays.…”

Mitigating the geometrical limitations of conventional sputtering by controlling the ion-to-neutral ratio during high power pulsed magnetron sputtering

“…(1)) is not well-defined since the width of 16 the race track is significant with respect to the target-substrate distance. Taking into account the curvature of the race track, and the cosine distribution of the sputtered material flux it can be estimated that  varies effectively between 70° and 78°, thus somewhat outside of the applicability limits of the tangent rule [7]. Nevertheless, in the case of reference DCMS sample the average column tilt is 57° which upon application of the tangent rule (Eq.…”