Masking technique

Visibihty tints are similar to cosmetic tints except that they are significantly lighter ki kitensity. Visible light transmission losses are typically 1—2%. With these tints, the lens is visible ki the lens package and against a variety of surfaces, and the lens is easier to handle. The tint can be added as cosmetic tints, with a masking technique to produce a clear annulus, or the whole lens can be tinted. 

A shadow-mask technique has been applied for the local metal deposition to exclude metal residues on other designs processed on the same wafer (Fig. 4.2b). Such metal residues may be caused by imperfections in the patterned resist due to topographical features on the processed CMOS wafers or dust particles. The metal film is only deposited in those areas on the wafer, where it is needed for electrode coverage on the microhotplates. This also renders the lift-off process easier since no closed metal film is formed on the wafer, so that the acetone has a large surface to attack the photoresist. Another advantage of the local metal lift-off process is its full compatibility with the fabrication sequence of chemical sensors based on other transducer principles [20]. 

Figures 23-28 show the process of producing basic circuit elements of vertically stacked circuits. The use of the three lithographic masking techniques mentioned results in very low loss transitions between optical circuits in different vertical stacks. These techniques can also be used to fabricate the low loss electro-optic modulator configuration shown in Figs. 29 and 30.

Localized reactions at solid/liquid interfaces driven by focused laser light can be phenomenologically divided into deposition and dissolution processes as well as substrate modification. They can be used either for analytical or preparative purposes. An example is a direct writing procedure for the preparation of microstructures on macroscopic substrates without any masking technique. 

After the bottom pole and insulator, a microwinding Cu coil is electrode-posited [121]. The insulator has to be prepared for the electrodeposition of Cu. This preparation involves the deposition of Cr/Cu bilayer by sputtering or evaporation. First, a thin layer (10 nm) of Cr is deposited onto the insulator. The function of the Cr layer is to provide a bonding layer between the insulator and Cu. A thin (50-100 nm) layer of Cu seed layer is then sputter deposited on Cr layer to provide sufficient electrical conductivity for subsequent electrodeposition of Cu. Cu is electrodeposited using deposition-through-mask technique. After electrodeposition of Cu coil, an insulator layer is deposited between the coil and the top pole layer. The top Permalloy pole is electrodeposited in the same way as the bottom pole layer, on thin sputter-deposited Permalloy underlayer (50-100 nm). The top and bottom pole layers are in contact. Finally, Cu interconnect pads, about 25-pm thick, are electrodeposited. The entire structure, poles and coil, is protected by an overcoat, usually sputtered AI2O3. The dimensions... 

In response to requirements and manufacturing approaches, different patterning techniques have been developed. Photolithographic techniques similar to those used in Si technology [42, 43] are used. Shadow mask techniques are well... 

In order to avoid the infiltration of seeds in the support and to develop ultra-thin membranes (typically 500 nm thick) with a high permeability, a masking techniques has been recently developed in Lulea University [111]. A solution of poly methyl methacrylate (PMMA) in acetone was applied and dried on the support top surface. The interior of the support was subsequently filled with wax and the protective PMMA layer was dissolved in acetone. The masked support was then seeded with a monolayer of silicalite-1 crystals before being submitted to the classical hydrothermal and calcination steps. 

Most of the preparation techniques mentioned above allow lateral patterning of thermo-responsive cell culture carriers by simple masking techniques. This includes ultraviolet (Chen et al. 1998) and electron beam irradiation (Tsuda et al. 2005) as... 

Often, the reaction rates of closely related components of a mixture with a common reagent are similar, and the rates cannot be sufficiently separated by either a thermodynamic or a kinetic masking technique to permit the faster or slower reacting component to be neglected. When this specific situation occurs, differential reaction-rate... 

Unlike silicon, the monoxide phase is volatile at the temperature of its formation from elemental components and, therefore tends to make direct thermal oxidation difficult as a passivation and masking technique. 

Absorption Mask Techniques Using Low-Energy Electron Beams... 

Other techniques may be applied. Future high-tech applications can use the advantages of locaKzed passivation and localized breakdown. Electrochemical passivation can be localized by mask techniques, for... 

Fig.l Schematic representations of various masking techniques and sample configurations, (a) Flag electrode (b) wire loop electrode (c) sample painted with protective coating (d) sample mounted in epoxy or other metallographic mount. The wires for electrical... 

IMAGING WITH TWO ANGULAR SCALES USING CODED MASK TECHNIQUES... 

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