Film uniformity

In the following sections we describe simulation results providing new Insights Into general MOCVD reactor behavior as well as the two major practical considerations, film uniformity and Interface width. 

Self-assembly methods have been used to form zinc bisquinoline assemblies with high refractive index and film uniformity.287... 

Is the film uniform in composition, or is there more than one layer ... 

The final film thicknesses were increased either by increasing the deposition time or by multilayer deposition. Although the film thickness increases with longer deposition time, the film morphology tends to be poor, as shown in Fig. 7.9. A two-layer technique that used two layers of TBSBCCO films, with an intermediate layer of Ag, improved the film uniformity and morphology, as shown in Fig. 7.10. The deposition process for the multiple layer is as follows (1) Single-crystal substrates are coated with 300 A of Ag (2) TBSBCCO films (0.4-1.3 pm) are prepared by electrodeposition (ED) on Ag/LAO (3) 300 A of Ag are deposited on ED-TBSBCCO/Ag/LAO (4) the second layer of TBSBCCO is electrodeposited (0.4-1.3 pm) on Ag/ED-TBSBCCO/Ag/LAO and (5) the complete two-layer system is reacted. 

Full generation poly(amidoamine) (PAMAM) dendrimers possessing amino surface groups are easily spread by spin coating on a mica surface to form films. Interdendrimer assembly events appears to influence these operations. Regardless of the generation levels examined, the film uniformity is determined primarily by the concentration of the dendrimer solution. 

LINEWIDTH CONTROL Lens imperfections Source stability Mask dimensions Beam shape Mechanical stability Developing Etching Baking Plasma descum Film thickness Film uniformity Swelling... 

The platens on which wafers are polished have also evolved over time. Traditional polishing, as is done on first- and second-generation CMP tools, is done on a hard platen. The reason for a hard platen, of course, is to present as close to absolutely flat a surface as possible against which the wafer is pressed. Ideally, platens rotate perfectly. In practice, however, there is a small amount of run-out, or wobble, which limits the ability of the tool to polish films uniformly, especially at high rotation speeds. 

They calculated heats of adsorption from the measured rise in temperature of the glass on which their metal films were deposited. This rise was about 0.1 °C. Their procedure was to admit an increment or shot of gas sufficient to cover the atomic surface to about one fifth of a monolayer (i.e., one adatom for five metal atoms). They assume that each shot covers the metal film uniformly throughout its depth. We believe that... 

Low-Pressure CVD Processes. Low-pressure CVD (LPCVD) (—101 Pa) is the main tool for the production of polycrystalline Si dielectric and passivation films used in Si IC (integrated-circuit) manufacture (1, 20, 21). The main advantage of LPCVD is the large number of wafers that can be coated simultaneously without detrimental effects to film uniformity. This capability is a result of the large diffusion coefficient at low pressures, which... 

Mathematical models that incorporate both flow and evaporative-loss mechanisms have been prepared (158). Non-Newtonian features have been introduced recently to refine the modeling efforts and have resulted in models with quantitative predictive abilities (159). Hence, data comparison between films spun on different spinners, with nominally identical final rotation speeds, may reveal differences in film uniformity. 

As long as the film is not reflective (i.e., specular aluminum) and is deposited on a reflective substrate (i.e., Si02 on silicon), optical techniques are available. It was recognized early that the color of a thin film could be correlated to its thickness. Although not very precise, such information is very useful for quick evaluation in the laboratory. For example, silicon dioxide films on silicon substrates can be evaluated with the data of Table 1. In fact, one of the more useful aspects of this technique is that one can make rapid judgements as to film uniformity. 

The lubricant dynamics can alter the nanoscale aerodynamics of the slider. Conversely, the lubricant morphology and dynamics may be altered because of the presence of the slider. For these types of applications, a molecule-level understanding of the lubricant interaction with nanoscale airbearing and solid surfaces is critical. The HDD industry must cope with problems of lubricant film uniformity, roughness [5], durability [6], and stability [7] in order to achieve its goal of increasing areal density. 

Plasma deposition and etch rates are affected by a large number of process parameters and physicochemical processes, illustrated schematically in Fig. 2, making the development and operation of plasma processes difficult. Moreover, given a particular process chemistry, it is not obvious how readily accessible parameters (e.g., feed rate, pressure, power, and frequency) should be manipulated to obtain the desired film uniformity and material properties. Glow discharge physics is complex, and the chemical mechanisms are not well known, in particular those underlying the plasma-surface interactions. Consequently, there is considerable incentive for gaining... 

Low-pressure CVD [187] of inexpensive materials such as plastics as substrate Improved film uniformity... 

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