Aluminum film etching

Chlorine-based plasma etching of aluminum films causes serious degradation of photoresist materials. To some extent, these effects are a result of the etch product, AICI3. Aluminum trichloride is a Lewis acid used extensively as a Friedel-Crafts catalyst. Therefore, it is hardly surprising that this material reacts with and severely degrades photoresists (74). 

Copper additions to aluminum films enhance electromigration resistance. However, copper does not form volatile chlorides or other halides, and therefore its removal during aluminum plasma etching is difficult. Two methods can be used to promote copper chloride desorption increase the... 

A second coating of nickel is then electrodeposited onto the mother disc. This nickel layer, the stamper master, is peeled off and used to stamp the data impression onto melted polycarbonate plastic discs. The polycarbonate disc now has all of the pits found on the original glass master disc etched by the laser. Because polycarbonate is clear, it is vacuum coated with a thin aluminum film to produce the reflective layer required by the laser. This delicate aluminum layer is covered with a protective layer of polycarbonate to prevent aluminum oxidation and marring of the data surface. The back of the CD can now be covered with information in the form of art and lettering. 

PAA films were formed b y anodization of A1 foil o f 100 im thickness i n o xalic (40 g/1, sample 1) and tartaric (60 g/1, sample 2) acids at constant current density of 10 mA/cm. According to the measurements in optical microscopy and SEM the thickness and period of structure averaged for the sample 1 were about 42 pm and 100 run for the sample 2-about 6 pm and 500 nm, respectively. After the oxide formation a non-oxidized aluminum was etched selectively to produce a transparence window for optical measurements. Finally, the samples were rinsed in DI during 10 min and then dried in air at 150 °C. 

Pore etching allows to rich the porosity up to 60 % and the pore entrances up to 20-30 nm (Fig. lc). In this case the LC alignment has vertical orientation as shown in Fig. Id. The top left part in Fig. Id is planar non anodized area of the initial aluminum film with the horizontal LC alignment. It should be noted that LC penetration in the alumina porous structure with 60 % porosity was almost complete. 

FM73 (rubber modified 120 °C curing film Etched aluminum 2,107 [14]... 

Electrical measurement of the dielectric constant is done through the fabrication of metal—oxide—semiconductor capacitor structures, where the ULK serves as the dielectric of the capacitor. A doped Si wafer is used as the substrate, on which the ULK film is deposited. This ULK film is subjected to CMP, say, or any other process whose impact on ULK characteristics needs to be quantified. An aluminum film is deposited on the backside of the Si wafer to form one of the capacitor contacts. Using a shadow mask, aluminum dots of varying diameters are evaporated onto the surface of the ULK film, to form the other terminal of the capacitor. Each aluminum dot is probed to measure its capacitance (at about 100 kHz). Evaporation through a shadow mask allows for the formation of metal contacts without altering the dielectric further— as would be the case if reactive-ion-etch were used to form the contacts. (It should be noted that more complex process flows can be used to eliminate concerns such as dot-size variation, the effect of probe-tip impact on the dielectric being tested, etc.) The results of electrical measurement of the k-value increase post-CMP of the variety... 

Consider the isotropic aluminum film on sihcon substrate, which is discussed in problem 4. If this film is etched into unidirectional fines, of tfie same thickness as the film, and with I fim width and 2 m spacing. 

In order to prevent aluminum from spiking through shallow junctions, 1-2% silicon is often added to the film. Since SiCl4 is volatile at room temperature, aluminum-silicon films can be readily etched in chlorine-containing gases. 

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