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Trimming thin films

A final alternative for metal patterning is the use of lasers to selectively and accurately etch small metal areas. Lasers are routinely used to trim thin-film resistors (126) they may also be used to repair defects or etch conductor lines by direct ablation in an inert atmosphere (127,129) or by laser-initiated etching in a reactive gas or liquid (128). [Pg.493]

The milled stock (111 parts) was dispersed in CH2C12 and a solution of f-butylphenolic resin (40 parts) in CH2C12 was stirred in. Additional CH2C12 was added so that the final slurry had 20% solids. The solvent was then evaporated and a thin film was produced. This film was pressed against the prepared substrate and covered with a sheet of finely-woven cotton cloth. The final sandwich was first pressed in a mold for 30 min at room temperature and 25,000 lb on a 5 in. ram and then cured for 40 min at 150°C and 30,000 lb on a 5 in. ram. The thickness of the elastomer layer in the resulting cloth-elastomer-substrate sandwich was 0.4 mm. Peeling experiments were carried out on strips of cloth-backed elastomer layer after trimming them to a uniform width on the substrate of 2 cm. [Pg.579]

To circumvent the limitations described above, Plummer et al. have used a different method, suitable for observation of plastic zones in bulk samples [30]. They embedded a DCB sample in a low viscosity epoxy resin with the razor blade in place. The crack tip was therefore maintained under stress while the resin was left to cure at room temperature. The sample was then trimmed for thin sectioning, stained by immersion in a Ru04 solution, and microtomed in thin sections in the region of the plastic zone for observation by TEM. While this method gave particularly good results on ductile semicrystalline systems where a deformed thin film would not have been representative of the plastic deformation mechanisms taking place in bulk samples, it should in principle be applicable fairly generally. [Pg.68]

Figure 5.2.1 shows a photograph of an integrated surface-micromachined accelerometer, and Figure 5.2.2 is a close-up of the surface-micromachined polysilicon MEMS structure near the center of Figure 5.2.1. The structural material is 3 pm thick polysilicon and the IC process is bipolar and CMOS (BiCMOS) with thin film resistors. This structure thus combines bipolar transistors, CMOS, precision laser-trimmed resistors, and mechanical polysilicon [4],... Figure 5.2.1 shows a photograph of an integrated surface-micromachined accelerometer, and Figure 5.2.2 is a close-up of the surface-micromachined polysilicon MEMS structure near the center of Figure 5.2.1. The structural material is 3 pm thick polysilicon and the IC process is bipolar and CMOS (BiCMOS) with thin film resistors. This structure thus combines bipolar transistors, CMOS, precision laser-trimmed resistors, and mechanical polysilicon [4],...
For thin-film resistors the heat diffusion into the substrate is dominant for aU but extremely short pulses. The effective heat capacity is proportional to the surface area thus, large resistors here ako are at an advantage. Breakdown usually occurs at spots where the current density is high, for instance at the end of trimming groove. Irregularities in the film may compHcate matters even more. Nevertheless, it k possible to make mathematic models of the pulse behavior of such resistors that accurately predict the maximum allowed pulse power under specified conditions. An example of such a calculated curve is given in Fig. 2.23. [Pg.162]

Resistor Trimming Comparison ofThick Film and Thin Film Technologies The Hybrid Assembly Process... [Pg.1259]

BeryUia may be metalUzed with thick film or thin film, or by one of the copper processes. However, thick-fihn pastes must be specially formulated to be compatible. Laser or abrasive trimming of BeO must be performed in a vacuum to remove the dust. [Pg.272]

The finishes produced have very good light fastness and corrosion resistance, and, unlike integral colour finishes, the shade is largely independent of the aluminium alloy and the anodic film thickness used. The whole range of shades can be produced on films as thin as 5 /im, so the finishes are also being used in trim applications. Many patents and publications in the electrolytic colouring field now exist and they have been reviewed by many authors . [Pg.702]

If excess material were added to the bank without lateral transport the bank would grow in size but in fact material is transported towards the edges of a film, beyond the edges of the feed and so increasing the width of the product. Usually, after the ultimate nip, an excess width of film is trimmed away as waste if this is not done care must be taken to make sure there is no variation in the surface finish in the areas of extended width. Occasionally a thin line of roughness will indicate the end of the width of material on Roll 3, and in the extended area flow marks are more likely to be found. [Pg.56]

The equipment used for extrusion coating is similar to that used for the extrusion of flat film. Figure 2.30 shows a typical extrusion coating setup. The thin molten film from the extruder is pulled down into the nip between a chill roll and a pressure roll situated directly below the die. The pressure between these two rolls forces the film on to the substrate while the substrate, moving at a speed faster than the extruded film, draws the film to the required thickness. The molten film is cooled by the water-cooled, chromium-plated chill roll. The pressure roll is also metallic but is covered with a rubber sleeve, usually neoprene or silicone rubber. After trimming, the coated material is wound up on conventional windup equipment. [Pg.187]

Applications automotive, bottles, Christmas tree, conduit, corrugated clear roofing, electrical and electronic appliance honsing, exterior trim, fence/deck/rail, glossy surface, injection molded prodncts, packaging film, pipe, ribbed pipe, roofing, siding, sheet, thin-wall parts, window profiles... [Pg.60]

Using QCM detection, a wide variety of conditions with respect to MIP material, preparation method and film thickness had been applied successfully few nm thin titan dioxide imprinted for azobenzene derivatives [46] (cf. Section III.C.l), 10 nm thin electropolymer imprinted for glucose [75] (cf. Section IH.C.2), 100 nm thin PUR imprinted for polar organic solvents [59] (cf. Section HI.C.2), 2 pm thin PMAA-co-TRIM imprinted for 5 -propanolol [54] (cf. Section HI.C.2), 50 pm thick porous PAN-co-AA imprinted for caffein [35] (cf. Section III.D.2), and 30 pm thick macroporous nylon imprinted for L-glutamin [36] (cf. Section III.D.2). [Pg.472]


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See also in sourсe #XX -- [ Pg.139 ]




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