Layers, epitaxial inorganic

Atomic layer deposition (ALD), originally termed atomic layer epitaxy, was pioneered and patented by T. Suntola and coworkers for growing ZnS (Suntola and Antson, 1977). Initial motivation for the development of ALD came from thin film electroluminescent displays. After extensive research advances in the past 40 years, ALD, which allows deposition at the atomic or molecular level, can be used for a variety of thin films such as metal oxides and nitrides, polymers, and inorganic—organic... 

It is known from the well-documented inorganic epitaxy studies that substrates play a crucial role in determining the adlayer structures. Related rules have been established for organic layers [215]. Parameters Uke the atomic lattice constant, crystalline orientation, and atomic steps have to be taken into... 

Table 4.2. Epitaxial deposition of inorganic crystals on insoluble substrates in which the final orientation is established through intermediate layers of different orientation ...

Molecular-beam epitaxy is a technique that has mainly been used by the semiconductor industry for producing thin hlms of compound semiconductors (e.g., GaAs and InP) used in the fabrication of LEDs, laser diodes, etc. Because these inorganic semiconductors are ceramics it should not be surprising that the technique can also be used to grow other ceramic thin hlms, such as the high-temperature superconductor YBaiCusOy. In fact, MBE is ideal for ceramics that have layered structures because it allows precise sequential deposition of single monolayers. 

Monolayers provide a two-dimensional matrix to mimic the biomineralization process for growing inorganic thin films or crystals [187]. The main concept behind this approach is the view pioneered by Lowenstam [188] that protein layers like, for example, the b-sheets in nacre, have an epitaxial arrangement of functional groups to specific crystal faces. The influence of surfactant headgroups with different functionalities on the crystallization of CaCOs [189-191] and BaS04 [192-194], under control of monolayers which are formed from saturated long alkyl chain carboxylates, sulfates, amines, and alcohols, has been studied. 

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