Plastic mold packages

Standardized plastic mold packages are the most cost-effective packages available. Packaging services are offered by large subcontractors, mainly located in South East Asia, which have established a worldwide standard for IC packaging. Therefore, flexibility for sensor-specific requirements is limited or even impossible, because existing manufacturing lines have to be used. Automotive quality is available, but not standard. 

Fig. 5.8.2 Typical plastic mold packages meter right angular rate sensor)...

The most signilieant application for conductive adhesives in the manufacture of microelectronics is the attachment of silicon chips to lead frames. Of the 40 billion integrated circuits (ICs) manufactured each year, approximately 90% are encapsulated in plastic-molded packages, and most of these are assembled with conductive adhesives [4]. A schematic illustration of a plastic-molded IC package is shown in Fig. 2. The conductive... 

A minimum temperature of 230°C is required to ensure adequate wetting and spreading by the Pb-free solder on circuit board pads as well as on component leads and terminations. Temperatures exceeding 245°C increase the likelihood of thermal damage to larger, plastic-molded packages (e.g., BGA and QFP devices). When temperatures exceed 260°C, there is the potential for thermal degradation of passive chip components (chip capacitors, indnctors, or filters) as well as to circuit board structures (e.g., vias) and laminate materials. In the case of Sn-Pb eutectic solder that melts at 183°C, the minimum process temperature of 215°C ensures adequate solderability, which is 15°C lower than that of a nominal Pb-free process. The available Sn-Pb process window is 215°C to 260°C, or a AT equal to 45°C, rather than the AT of 30°C for the Sn-Ag-Cu Pb-free solders (T di = 217°C). 

J. Hirota and co-workers, "The Development of Copper Wire Bonding for Plastic Molded Semiconductor Packages," 35th Electronic Component Conference Proceedings,S3J2Lshm.g. on,E).Q. 1985, pp. 116—121. 

Plastic molded clasps are commonly used to secure tops and lids on different type packages. Their holding power can be obtained from simple friction between the joint surfaces or from positive mechanical engagement. Plastic flexing capability is important because the products must flex in order to... 

As we will see in Chapter 9, multilayer blow molding is sometimes used as a way to incorporate recycled polymer in food-grade bottles. For safety reasons the use of recycled plastics in packaging that comes in direct contact... 

The U.S. Environmental Protection Agency issued a final rule banning the use of CFC s in flexible plastics and packaging foams, among other uses, after February 15, 1993. Exceptions are CFC-11 and CFC-13 which can be used, temporarily, in mold release agents and the production of plastic and elastomeric materials. However, in 1994, no CFC s will be allowed in flexible foams in the U.S., and a tax will be levied on other CFC uses. Total CFC phaseout is mandated in the U.S. for 1995. 

Molded plastic. of packages to processing temp. >350 C (if silver-glass adhesives are used) High strength, low-temperature Silver-filled epoxy, modified... 

Figure 2 Cross section of a plastic-molded integrated circuit package.

There are numerous product standards. For electrical LVD products EN 60950 (Safety of ITE), EN 61010-1 (Safety of Measurement and Lab Devices), EN 60335 (Safety of Household and Similar Appliances). For machinery EN 415 (Safety of Packaging Machines), EN 201 (Safety of Plastics Molding Machines), EN 1010 (Safety of Paper Machines). 

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