Subject thin films

A belief that solid interfaces are easier to understand than liquid ones shifted emphasis to the former but the subjects are not really separable, and the advances in the one are giving impetus to the other. There is increasing interest in films of biological and of liquid crystalline materials because of the importance of thin films in microcircuitry (computer chips ), there has been in recent years a surge of activity in the study of deposited mono- and multilayers. These Langmuir-Blodgett films are discussed in Section XV-7. 

Metals that depend on a relatively thick protective coating of corrosion product for corrosion resistance are frequently subject to erosion-corrosion. This is due to the poor adherence of these coatings relative to the thin films formed by the classical passive metals, such as stainless steel and titanium. Both stainless steel and titanium are relatively immune to erosion-corrosion in most cooling water environments. 

On the broad subject of thin films generally, a well-regarded early text is by an Indian physicist, Chopra (1969), while a very broad, didactic treatment of thin films in all their aspects is by Ohring (1992). A recent survey of the effect of structure on properties of thin films relevant to microelectronics is by Machlin (1998). 

Thin films of oil in pipework can explode without a previous fire if subjected to sudden shock, for example, by rapid opening of a valve [20]. 

The combined effects of a divalent Ca counterion and thermal treatment can be seen from studies of PMMA-based ionomers [16]. In thin films of Ca-salts of this ionomer cast from methylene chloride, and having an ion content of only 0.8 mol%, the only observed deformation was a series of long, localized crazes, similar to those seen in the PMMA homopolymer. When the ionomer samples were subject to an additional heat treatment (8 h at 100°C), the induced crazes were shorter in length and shear deformation zones were present. This behavior implies that the heat treatment enhanced the formation of ionic aggregates and increased the entanglement strand density. The deformation pattern attained is rather similar to that of Na salts having an ion content of about 6 mol% hence, substitution of divalent Ca for monovalent Na permits comparable deformation modes, including some shear, to be obtained at much lower ion contents. 

Now consider the case of two-dimensional flow subjected to the lubrication geometry assumptions that result from analyzing the order of magnitude for the velocities in thin film flow ... 

Liquid lubricant confined in molecularly thin films would experience dramatic changes in its physical properties, such as increased viscosity, slow relaxation, and solidihcation. Progress in studies of thin film rheology has greatly improved our understanding of boundary lubrication, which is the subject to be discussed in this section and in the next. 

Meanwhile, study on ultra-thin film gas lubrication problems has become one of the most attractive subjects in the held of tribology during the past three decades. 

May, P. W. 2000 Diamond thin films a 21st-century material. Phil. Trans. R. Soc. Lond. A, 358, 473-495. This gives a much more thorough and detailed scientific account of the subject. 

The conformation of polymer chains in an ultra-thin film has been an attractive subject in the field of polymer physics. The chain conformation has been extensively discussed theoretically and experimentally [6-11] however, the experimental technique to study an ultra-thin film is limited because it is difficult to obtain a signal from a specimen due to the low sample volume. The conformation of polymer chains in an ultra-thin film has been examined by small angle neutron scattering (SANS), and contradictory results have been reported. With decreasing film thickness, the radius of gyration, Rg, parallel to the film plane increases when the thickness is less than the unperturbed chain dimension in the bulk state [12-14]. On the other hand, Jones et al. reported that a polystyrene chain in an ultra-thin film takes a Gaussian conformation with a similar in-plane Rg to that in the bulk state [15, 16]. 

Electric breakdown of growing alumina films limits their maximum attainable thickness. It also causes degradation of thin film electronic devices with alumina films. Hence, it is a subject of intensive research and a large number of papers have been published and further reviewed. A good deal of controversy exists on various aspects of alumina oxide breakdown, and a variety of models have been proposed in attempts to fit experimental findings. 

Subject of our investigations became thin films of tin deposited under high vacuum on different current collectors. 

A seminal contribution by Mansky et al. on the preparation of oriented thin films of PS-PBD block copolymers that were then subjected to ozonolysis degradation conditions to give porous thin films for use as nanolithography... 

Information on the dielectric properties of a material might also be obtained using noncontact scanning techniques. These can include rf or microwave measurements made with an electrode that is held in the vicinity of the surface. This approach has the advantage that samples remain undamaged by the measurement and thus can be reevaluated or subjected to other studies as needed. However, this approach cannot provide accurate values for the capacitance, in very thin films such that d/e < 4 A. Moreover, the current-voltage measurements are still needed in order... 

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