Continuous polycrystalline films

Sintering Metal and Semiconductor Nanoparticles into Continuous Polycrystalline Films... 

Island growth also occurs with polycrystalline films, but in epitaxy, the islands combine to form a continuous single-crystal film, that is, one with no grain boundaries. In reality, nucleation is much more complex in the case of heteroepitaxy. Nucleation errors may result in relatively large areas, or domains, with different crystallographic orientations. The interfaces between domains are regions of structural mismatch called subgrain boundaries and will be visible in the microstructure. 

A formulation leading to a continuous polycrystalline MFI film was (molar ratio) ... 

So far, essentially three different approaches have been reported for the preparation of zeolitic membranes [119]. Tsikoyiannis and Haag [120] reported the coating of a Teflon slab during a "regular" synthesis of ZSM-5 by a continuous uniform zeolite film. Permeability tests and catals ic experiments were carried out with such membranes after the mechanical separation of the coating from the Teflon surface [121]. Geus et al. [122] used porous, sintered stainless steel discs covered with a thin top layer of metal wool to crystallize continuous polycrystalline layers of ZSM-5. Macroporous ceramic clay-type supports were also applied [123]. 

X in PDAs and are of continuing interest. However, poly-PTS crystals grown to date do not have optically flat surfaces, and their study has been facilitated by immersion in diiomethane, which has a refractive index comparable to the polymer in the near infrared region (13). Thin polycrystalline films of poly-PTS (16) do not improve the situation in that they have significant transmission losses in the near infrared (17). 

Although cBN is metastable at low pressures, it can be synthesized below 1 bar in a manner similar to the formation of diamond at low pressures. In the early 1980s, a small amount of cBN was claimed to exist with a large amount of hBN (or tBN) in a BN deposited film. At present, a small amount of hBN (or tBN) remains in a cBN polycrystalline film although the cBN crystals forming the film are extremely small (< 0.1 Ltm). Studies of low-pressure methods for producing cBN films are continuing with a view to future applications. 

Hara, A. Takei, M. Takeuchi, F. Suga, K. Yoshino, K. Chida, M. Kakehi, T. Ebiko, Y. Sano, Y. Sasaki, N. 2004. High performance low temperature polycrystalline silicon thin film transistors on non-alkaline glass produced using diode pumped solid state continuous wave laser lateral crystallization. Jpn. J. Appl. Phys., Pt. 1 43 1269-1276. 

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