Bonding aluminum layers

Aluminum/Mylar/AIuminum (0.0024 in.) 5 Bond between film and laminate O.K. Very slight wrinkles in film Same as 10% Bond between layers broken— wrinkles in bonded aluminum layer Mylar film broken—bonded aluminum foil cracked... 

It should be noted that a number of aluminum alloys are available (see Table 28-16). Many have improved mechanical properties over pure aluminum. The wrought heat-treatable aluminum alloys have tensile strengths of 90 to 228 MPa (13,000 to 33,000 Ibf/in ) as annealed when they are fuUy hardened, strengths can go as high as 572 MPa (83,000 Ibf/in"). However, aluminum alloys usually have lower corrosion resistance than the pure metal. The alclad alloys have been developed to overcome this snortcoming. Alclad consists of an aluminum layer metaUurgicaUy bonded to a core alloy. 

The Alclad alloys have been developed to overcome this shortcoming. Alclad consists of a pure aluminum layer metallurgically bonded to a core alloy. The corrosion resistance of aluminum and its alloys tends to be very sensitive to trace contamination. Very small amounts of metallic mercury, heavy-metal ions, or chloride ions can frequently cause rapid failure under conditions which otherwise would be fully acceptable. When alloy steels do not give adequate corrosion protection—particularly from sulfidic attack—steel with an aluminized surface coating can be used. 

Another very important group of materials, the clays, are formed from silicon-oxygen sheets. In this case, however, the sheet is not the simple one shown in Fig. XXVI-4, but each sheet is bound by homopolar valences to another sheet of different composition. For instance, in kaolinite, one form of clay, one starts with a silicon-oxygen sheet. Above that, there is an aluminum layer, with as many aluminums as silicons, bonded to the oxygens. The other bonds of the aluminums extend to a... 

The rudimentary IC that Kilby made contained one bipolar transistor, three resistors, and one capacitor, all made in germanium and coimected by wire bonding. For his invention of the IC, Jack Kilby was awarded the Nobel Prize in physics in 2000." The monolithic (monolith means single stone ) IC that Noyce proposed in 1959 was a flip-flop circuit containing six devices, in which the aluminum interconnection lines were obtained by etching an evaporated aluminum layer over the entire oxide surface using a lithographic technique. ... 

Same as above Same as above Wrinlcles in film but film and all bonds O.K. Bonds between layers broken— top aluminum and Mylar layers O.K. 

Aluminum products sometimes are coated on one or both surfaces with a metallurgically bonded, thin layer of pure aluminum or aluminum alloy (Fig. 7). If the combination of core and cladding alloys is selected so that the cladding is anodic to the core, it is called... 

Hollow Fiber with Sorbent Walls. A cellulose sorbent and dialy2ing membrane hoUow fiber was reported in 1977 by Enka Glan2stoff AG (41). This hoUow fiber, with an inside diameter of about 300 p.m, has a double-layer waU. The inner waU consists of Cuprophan ceUulose and is very thin, approximately 8 p.m. The outer waU, which is ca 40-p.m thick, consists mainly of sorbent substance bonded by ceUulose. The advantage of such a fiber is that it combines the principles of hemodialysis with those of hemoperfusion. Two such fibers have been made one with activated carbon in the fiber waU, and one with aluminum oxide, which is a phosphate binder (also see Dialysis). 

Aluminum, the most common material used for contacts, is easy to use, has low resistivity, and reduces surface Si02 to form interfacial metal-oxide bonds that promote adhesion to the substrate. However, as designs reach submicrometer dimensions, aluminum, Al, has been found to be a poor choice for metallization of contacts and via holes. Al has relatively poor step coverage, which is nonuniform layer thickness when deposited over right-angled geometric features. This leads to keyhole void formation when spaces between features are smaller than 0.7 p.m. New collimated sputtering techniques can extend the lower limit of Al use to 0.5-p.m appHcations. 

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