Integrated circuit plastic

The acoustic microscopy s primary application to date has been for failure analysis in the multibillion-dollar microelectronics industry. The technique is especially sensitive to variations in the elastic properties of semiconductor materials, such as air gaps. SAM enables nondestructive internal inspection of plastic integrated-circuit (IC) packages, and, more recently, it has provided a tool for characterizing packaging processes such as die attachment and encapsulation. Even as ICs continue to shrink, their die size becomes larger because of added functionality in fact, devices measuring as much as 1 cm across are now common. And as die sizes increase, cracks and delaminations become more likely at the various interfaces. 

The growth of electroless plating is directiy traceable to (/) the discovery that some alloys produced by electroless deposition, notably nickel phosphoms, have unique properties (2) the growth of the electronics industry, especially the development of printed circuits (see Electronic coatings Integrated circuits) and (i) the large-scale introduction of plastics into everyday life. 

OFETs constructed on a silicon wafer do not lake advantage of one of the main interest of organic materials, namely the possibility of building electronic devices on plastic substrates. A second important drawback of the silicon-based structure is the difficulty to individually address the gale of transistors built on the same wafer, which would prevent the achievement of integrated circuits. 

Also called conformal coating. It encloses a product in a closed envelope of plastic by immersing the product (solenoids, ornament, sensors, motor components, integrated circuits, and other articles.) in an unheated or... 

Figure 13.12. Images and electrical measurements of integrated circuits that use semiconductor wires and ribbons on plastic, (a) Silicon ribbon five-stage ring oscillator and (b) differential amplifier. (Reprinted with permission from Ref. 87. Copyright 2007 American Institute of Physics.) (c) GaAs logic gates. (Reprinted with permission from Ref. 86. Copyright 2006 Wiley-VCH Verlag.)...

Ahn, J. H. et al. 2007. Bendable integrated circuits on plastic substrates by use of printed ribbons of single-crystalline silicon. Appl. Phys. Lett. 90 213501. 

Examples of conductive ABS polymer composites include electromagnetic shielding materials (56,57) and electrically conductive composite plastic sheets, which may be used for packaging of integrated circuit devices (58,59). 

When phosphorus is added to Si02, in addition to gettering mobile alkali ions, it tends to reduce the intrinsic tensile stress in such films, thereby reducing their tendency to crack. Both functions are important when the film is used as a final passivation film for integrated circuits encapsulated in plastic. Phosphorus additions of 7 weight percent seem to be optimum in order to produce the above desirable film characteristics. 

PECVD of silicon nitride has been of commercial importance since 1976.1 The original motivation was to find a final passivation layer for an integrated circuit that would replace the doped silicon dioxide films then in use. The latter were not reliable enough to permit packaging of integrated circuits in plastic. Silicon nitride was recognized as a better final passivation film, but the only available technique for its deposition was the high-temperature thermal process. Since it had to cover an aluminum final metallization layer that would melt at 600°C, this clearly could not work. The solution was to use PECVD at 350° to 400°C. 

The commercial integrated circuit (chip) is normally encapsulated in a thermoset plastic molding compound to protect the chip and permit handling and subsequent assembling without loss of circuit integrity. However, the increasing complexity of the chip has... 

K. Miyake et al., Thermal Stress Analysis of Plastic Encapsulated Integrated Circuits by FEM, lECE Proc., Japan, 1984, p. 2833. 

DIP (Dual Inline Package) A standard housing constructed of hard plastic commonly used to hold an integrated circuit. The circuit s leads are connected to two parallel rows of pins designed to fit snugly into a socket these pins may also be soldered directly to a printed-circuit board. If you try to install or remove dual inline packages, be careful not to bend or damage their pins. 

Studies on thermomechanical stresses in plastic packaged integrated circuits after molding and in encapsulation materials, show the resulting stress distribution on the surface of the die and clarify the fundamental mechanism in the generation of thermomechanical stresses in molding compounds. 

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