Polymer interlayer insulating interlayers

Manufacture of Printed Wiring Boards. Printed wiring boards, or printed circuit boards, are usually thin flat panels than contain one or multiple layers of thin copper patterns that interconnect the various electronic components (e.g. integrated circuit chips, connectors, resistors) that are attached to the boards. These panels are present in almost every consumer electronic product and automobile sold today. The various photopolymer products used to manufacture the printed wiring boards include film resists, electroless plating resists (23), liquid resists, electrodeposited resists (24), solder masks (25), laser exposed photoresists (26), flexible photoimageable permanent coatings (27) and polyimide interlayer insulator films (28). Another new use of photopolymer chemistry is the selective formation of conductive patterns in polymers (29). 

Insulating interlayers separates the inclusions from each other and from the matrix polymer in such system degradation catalyzed by nanoparticles starts within the interlayer. This layer should provide less combustible degradation products. A new method for the formation of PEP resin has been proposed recently [21]. A detailed analysis of PEP revealed the combined (gas and solid phase) mechanism of FR action in this material [41], This polymer was selected for forming an interlayer around clay nanoparticles. The monomer components were introduced during the compounding process and the interlayer was formed by in situ curing. 

Chapters 1 and 2 introduce the CMP process and historical motivations. The present status of CMP is discussed in Chapter 2, which focuses on establishing the need of advanced metallization schemes and planarization. There are a large number of variables that control the process these are discussed in Chapter 3. Chapter 4 presents the science of CMP— mechanical and chemical concepts important in understanding the CMP fundamentals. The CMP of the Si02 films, the most commonly used insulator interlayer dielectric, is discussed in Chapter 5. Chapters 6 and 7 cover the CMP of the two most studied metals, W and Cu, respectively. Chapter 8 examines the applicability of CMP to new materials, e.g., Al, polymers, and Si3N4 photoresists. Finally, Chapter 9 covers post-CMP cleaning science and technology. 

High-temperature resists have been formulated from a group of polyesters based on styrylpyridine, which are thermally stable up to 450°C. Such resists have found applications as fine-line solder masks or when the polymer is intended as a permanent eomponent of the final deviee, he it as insulator, interlayer dielectric, or a-particle harrier. ... 

The percolation theory [5, 20-23] is the most adequate for the description of an abstract model of the CPCM. As the majority of polymers are typical insulators, the probability of transfer of current carriers between two conductive points isolated from each other by an interlayer of the polymer decreases exponentially with the growth of gap lg (the tunnel effect) and is other than zero only for lg < 100 A. For this reason, the transfer of current through macroscopic (compared to the sample size) distances can be effected via the contacting-particles chains. Calculation of the probability of the formation of such chains is the subject of the percolation theory. It should be noted that the concept of contact is not just for the particles in direct contact with each other but, apparently, implies convergence of the particles to distances at which the probability of transfer of current carriers between them becomes other than zero. 

Since the invention of integrated circuits (ICs), polyimides as heat-resistant organic polymers have been applied to insulation materials in electronics devices such as flexible printed circuit boards (FPCs), interlayer dielectrics, buffer coatings, and tape automated bonding (TAB). A polyimide thin layer is easily... 

The electrical properties of polymers are important in many applications [1]. The most widespread electrical application of polymers is the insulation of cables. In recent years, high-performance polymers have become important in the electronics industry as encapsulants for electronic components, as interlayer dielectrics, and as printed wiring board materials. The dielectric constant (or permittivity) and the dissipation factor (or power factor or electrical loss tangent) tan 8, which are dimensionless quantities, are the key electrical properties. 

Capacitive interference, the signal delay caused by the permittivity of insulating layers, the minimum required interlayer dielectric thicknesses, and the power dissipation, can all be decreased by designing polymers with lower values of e. The synthesis of polymers which simultaneously have low values of and outstanding thermal and mechanical properties is therefore crucial for applications in the electronics industry. 

The polymers considered for these applications are primarily polyimides. Although polyimides have been used as electrical insulation for the past 15 years, and a considerable know-how has been generated about these polymers and their applications as insulation, their use in microelectronic devices provides new challenges. Because the interlayers are approximately 2um thick. 

Polyimide is one of the fastest growing materials in polymers for electronic applications. During the past couple of decades, there has been a tremendous interest in this material for electronic applications. The superior thermal (up to 500 °C) mechanical and electrical properties of polyimide have made its use possible in many high performance applications, from aerospace to microelectronics. In addition, polyimides show very low electrical leakage in surface or bulk and form an excellent interlayer dielectric insulators and excellent step coverage in multilayer IC structures. They... 

Organic polymers have attracted much interest in electrical and electronic applications because of their electrical insulating nature. Polyimides have gained much attention because of their excellent thermal stability and low dielectric constant. Polyimides have found applications in matrix resins for circuit boards, encapsulants, adhesives, passivation coatings, alpha particle barriers, ion implant masks and interlayer dielectrics."10... 

---