Multichip modules, application

Rigid-rod polymer films made from PBO and PBZT are being developed because they provide important performance improvements over competing materials such as fiber reinforced composites and metals. Table I summarizes some of the highest payoff applications. Thin PBZT films combined with low dielectric constant resins are being developed for multilayer circuit boards and multichip modules to increase interconnection density and speed with matched circuit impedance and reduced crosstalk. 

Structuring of polymers today is industrially used for the production of nozzles for inkjet printers [19] and to prepare via holes in multichip modules through polyimide (PI) by IBM [20], as well as for many other applications, for example, fabrication of microoptical devices [21] and microfluidic channels [22-25],... 

Qualihcation tests for adhesives are dehned in Method 5011 of MlL-STD-883 and requirements for qualifying sealed hybrid microcircuits or multichip modules that contain adhesives are specihed in MlL-PRF-38534. Space, automotive, and medical applications generally use the military specihcations, but are modihed or supplemented with additional tests and requirements for their particular application. 

The major applications of LCP films in electronics are multilayer boards and multichip modules, and flexible printed circuits. Current materials used in the.se applications include polyimide film, high performance thermoplastic film such as polyphenylene sulfide and polyetherether ketone, and fiber reinforced composites such as quartz fiber-polyimide. The price of these materials for electronic packaging is in the range of. 50 to. l(K)/lb, so LCPs can compete very effectively at their current prices. Based on a two to three times increase in price... 

MAJOR APPLICATIONS Polyquinolines C2m be processed into films and fibers and can be spin coated. An ideal choice for high-performance films, electronic coatings, as a matrix for high-performance composites, and as an interlayer dielectric substrate in multichip modules. 

Some adhesive materials and processes are used across many applications. For example, adhesives used to attach bare die and substrates in hybrid or multichip modules may be used for a wide variety of ground-based military... 

The major use of CE resins is in the electronic industry, including printed wiring circuit boards, thin cards, multichip module laminates and ship encapsulants. CE resins have replaced epoxy and bismaleimide resins to a great extent for such microelectronic application due to their comparatively lower moisture absorption and dielectric dissipation factor. 

Liu, Y., Bristow, J., Marta, T., Bounnak, S., Johnson, K., Liu, Y., and Cole, H., Polymer waveguide applications in multichip modules (MCMs) and board level optical interconnects. Organic thin films for photonics applications, OSA Tech. Digest Sen, 21, 14 (1995). 

This flip chip bonding technique has high potential to replace conventional solder flip chip techniques for sensor and actuator systems, optical microelec-tromechanical systems, optoelectronic multichip modules, and electronic system applications (55). 

The use of bare die in chip on board (COB) and multichip module (MCM) apphcations is increasing with designers looking for end item size and weight reduction (automotive applications have bond wires going directly from the die to a connector). The use of bare die eliminates the timing delays (caused by stray inductance and capacitance) associated with the leadfi ames and the device input/outputs (1/Os). For burst mode static RAMs, 1/2-2 ns or a 20% improvement in access time is achieved with bare die product. Small portable devices can also use flip-chip bonding. 

Reliability. The performance ofthe electronic devices implanted in the body is extremely important. Malfunctioning can result in death. For hybrid microcircuits and multichip modules, the qualification tests and accelerated tests required of military and space applications also apply, although some shock and vibration tests are not realistic for humans. In addition, the Food and Drug Administration (FDA) becomes involved in testing and reviewing... 

This multichip module was designed for military airborne communications applications where small size, high density, and low weight were critical to system performance. The module shown in Figure 1.20 is a 25.4-mm (1-in.) square package with a multilayer thick-film substrate with 125-pm (5-mil)... 

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