Molecular orientation in physical-vapour deposition of long-chain stearic acid

Orientation of tetragonal lysozyme crystals nucleated on fatty acid thin films

“…The structure of the thin behenic acid films fabricated by physical vapor deposition is strongly influenced by the deposition conditions, such as deposition rate, substrate temperature and substrate materials [5,6]. AFM images, cross-sectional profiles and structure models of behenic acid thin films are illustrated in Fig.…”

Influence of the crystallization solution on orientations of lysozyme crystals nucleated on fatty acid thin films

“…The structure of thin behenic acid films fabricated by physical vapor deposition is strongly influenced by the deposition conditions, such as deposition rate, substrate temperature and substrate materials [5][6][7]. At relatively low deposition rates, the films on a mica surface show twodimensional layers with normally oriented behenic acid dimers, while three-dimensional hillocks with lateral orientation grow at higher deposition rates.…”

Classical nucleation theory applied to molecular orientations in vapor-deposited organic thin films

“…2 The physical vapor deposition ͑PVD͒ method, sometimes termed vacuum evaporation or thermal deposition, can meet the requirements and has been considered as one of the most promising techniques for the preparation of highfunctional organic devices in electronics and optics. 3 For linear long-chain compounds, such as paraffin, [4][5][6] fatty acid, [7][8][9] alkyl diamine, 10 poly͑vinylidene fluoride͒ ͑PVDF͒, 11,12 poly͑p-phenylene͒ ͑PPP͒, 13 molecular orientations of vapordeposited films are strongly dependent on the deposition conditions, especially on the substrate temperature and the annealing temperature. In general, a high substrate temperature or a low deposition rate results in an orientation normal to the substrate surface, whereas a low substrate temperature or a high deposition rate gives rise to a lateral orientation or an amorphous structure.…”

“…Here it should be emphasized that Matsuzaki et al summarized the dependence of molecular orientation on the deposition conditions by using only one parameter, supersaturation, associated with both of the substrate temperature and the deposition rate. 7 Although it can actually produce organic thin films exhibiting such high molecular order, only a few organic devices are commercially produced by this method mainly because the film formation mechanisms of organic thin films are still uncertain or unknown and it is somewhat difficult to control the precise structure in comparison with the Langmuir-Blodgett ͑LB͒ technique. It is therefore necessary to understand the elementary processes and the mechanism of film formation for the precise control of the film structure.…”