High Density Interconnect Structures

IPC-2315 Design Guide for High Density Interconnecting Structures and Microvias ... 

IPC-6016 Standard for Qualification and Performance Specification for High Density Interconnection Structures ... 

IPC-4104 This standard identifies materials used for high-density interconnection structures. A series of specifications (slash sheets) are defined for specific available materials. Each sheet outlines engineering and performance data for materials used to fabricate high-density interconnecting structures. These materials include dielectric insulator, conductor, and dielectric/conductor combinations. The slash sheets are provided with letters and numbers for identification purposes. For example, if a user wishes to order from a vendor and reference the specification sheet number 1, the number 1 would be substituted for the S ... 

The core, defined as [C], can be identified as an A, B, or C type core. Thns, [CA] is a core with internal vias only redistribntion makes contact with the snrface. [CB] is core with internal and external (throngh microvia strnctnres). High-density interconnecting structures make contact with the innerlayers of the core. [CC] is passive core, in which there are no interconnections. 

Meiko-BU. Meiko Circuits of Japan takes a photoresist and coats it onto a stainless steel panel. This starts the process to produce high density interconnect structures (HDIS) in a remarkable way. The advantages of this process is that surface geometries are not determined by etching or full additive metallization, the vias are under the surface lands, and the circuits are all flush with the dielectric, permitting the elimination of solder masks. On the negative side, this is a more expensive process that involves carriers. 

PolyHIPE materials possess many peculiar properties as a result of their unique cellular structure. Referring specifically to open-cell polymers (which have received the most attention in the literature), they are characterised by a very low dry bulk density, typically less than 0.1 gem-3, due to their highly porous, interconnected structure. 

On one side the development is based on thin film and micro-patterning technologies. Wafer level and foil processes used to produce high density interconnect electronic modules, and wafer level packaging was adapted to micro fuel cell development to achieve the required miniaturisation and cost reduction. By using reactive ion etching, high aspect ratio capillary structures of the anode and cathode side flow fields were achieved. 

The major advantages of this technology include the ability to provide high-density interconnections with relatively short path lengths, which lead to higher-speed computers excellent thermal dissipation the ability to operate at elevated temperatures, excellent structural strength provision for a hermetically sealed transistor enclosure, excellent dimensional stability, and an overall low thermal coefficient of expansion. 

Structure This factor determines the number of signal layers and the combination of through and buried vias that permit interconnection between layers and the complex blind, stacked, and variable depth vias available in high-density interconnection (HDI) technologies. 

The Structure of the high-density interconnection is by type Type I,Type II,Type III,Type IV, Type V, and Type VI (see Table 22.2). However, some of these type constructions are based on which micro via material is to be used. Thus, the following definition applies to all high-density interconnect substrates (HDIS). 

Multilevel structures consisting of alternating metal and dielectric layers are necessary to achieve Interconnection in high density or VLSI circuits using either MOS or bipolar technology. 

In the Tbilisi area, the Middle Eocene sequence is a volcanic erupted structure with a very high density of interconnected micro fractures and a relatively smaller number of macro fractures with apertures in the mm range. The matrix rock is of low porosity and low permeability and is not considered to contain any significant reservoir volume. The fields have been producing since 1974 by open-hole wells of which a large number have experienced water break through. 

Figure 1.53 Thermal runaway vicious circle. Shrinking of TaMP leads to an increasing defect density due to a higher bulk oxygen concentration. The high associated leakage currents result in high temperatures, which induce further dislocations. Additionally, thermal runaway can occur due to the reduced thermal conductivity (lowersinter temperature leads to degradation ofthe interconnect structure, which reduces the thermal conductivity).

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