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High‐density interconnect (HDI) continues to be the fastest growing segment of the printed circuit board (PCB) market. The purpose of this paper is to discuss the differences in designing HDI compared to conventional PCB multilayers. This is important for the challenging aspects of very high‐speed electronics that require care to control signal integrity and power integrity.

Eight new design principles were studied and illustrated with emphasis on how these differ from conventional PCB design.

HDI implementation can be improved 2X to 4X by employing these new design principles. Densities from 6‐12 in. per sq. inch to 18‐48 in. per sq. inch have been reported. Design time reductions of 50 percent and cost reductions of 30 percent were also seen.

This work was focused on the basic design principles and does not address electronics design automation tools or specific design steps. PCB design is a complex activity and readers are encouraged to obtain and use the references cited.

The paper describes various design and layout procedures that the authors have learned over the last 29 years involved in printed circuit design and fabrication. These principles can be combined with other innovations to enable a much more beneficial use of HDI technologies.

The purpose of this paper is to present an updated overview of printed circuit manufacturing equipment from the perspective of “mechanization strategies and systems” in order to enable printed circuit board (PCB) manufacturers to select the appropriate equipment.

Ten process mechanization strategies were studied and illustrated with emphasis on the new conveyorized vertical plating and traditional horizontal conveyors, with some highlights of reel‐to‐reel chip on flex conveyorized plating equipment.

Novel mechanization continues to be created to enhance the technology, quality, and productivity of printed circuit manufacturing.

Mechanized equipment has the most controlled conditions for research and another publication referenced will supply information on sensors and controllers for modern high‐speed PCB processes.

The paper describes various mechanization strategies for equipment used in printed circuit manufacturing, combined with process sensors, automatic control, statistical design of experiments, and automation strategies that will present the best scenario for optimal PCB production.

This paper describes the power mesh architecture (PMA), a new interconnection topology which leverages the production technologies of microvias, via‐in‐pads and fine‐line lithography to allow planar power distribution and dense signal interconnection, on only two or four metal layers. The PMA was derived from the interconnected mesh power system (IMPS) developed and patented by the High Density Electronics Center (HiDEC) of the University of Arkansas. The IMPS topology was created to reduce the cost and metal layers on thin‐film and ceramic multichip modules. Power distribution characteristics of IMPS are presented as measured from various test vehicles. The PMA for PCBs is presented as well as impedance tables. The initial application of PMA is shown as well as an application that helps develop the wiring density model for PMA. Finally, the eight step design process is outlined to create a PMA board and an example of a notebook computer.

Microvias or high density interconnects (HDI) printed circuits are now being designed in ever increasing quantities. HDI brings some interesting new solutions to age‐old signal integrity (SI) concerns, and concerns that will grow as rise‐times continue to drop.This article focuses on five major areas of SI concerns—(1) noise: (a) noise‐reflections, (b) noise‐crosstalk, (c) noise‐simultaneous switching; (2) electro‐magnetic interference (EMI); (3) interconnect delays.In each case, HDI offers improvements and alternatives—but it is not a panacea. A couple of “cautions” are listed that can be a major stumbling block to HDI implementation, fortunately, they are not SI based. Important to SI is the materials used in HDI. Although not the focus of this article, the materials selected, as well as the dimensional stack‐up and PCB design rules, will influence SI and electrical performance (impedance, crosstalk and signal conditioning). Miniaturization provided by HDI will be a major contributor to SI performance.Finally, the SI example is also a case study in cost reduction. The “before” and “after” conditions are reviewed to emphasize the cost reduction and “time‐to‐market” advantages of HDI technology.

This paper reveals a new methodology for predicting the most efficient design rules to follow for high density printed wiring boards prior to physical layout. The only input is from a schematic diagram, parts list and proposed board size. The methodology attempts to a priori determine the wiring capabilities of different PWB designs for a given product application. The particular focus is the difference between through‐hole and HDI designs.

High density interconnect (HDI) printed circuits are now being designed in ever‐increasing quantities for very high‐speed applications. The challenge of opto‐electronics and integration of photonics into the printed circuit has started to take off. In the next 7 years, expectations are that photonic printed circuit boards will grow to a $2.5 billion industry. This paper looks at the issues, materials and current processes being researched by European, Japanese and North American organizations to create this integrated opto‐electronic circuit board. In addition to reviewing the global players in polymer photonics, this paper will review the current programs of four of the six groups globally, namely EOBC‐OptoFoil (University of Ulm, Fraunhafer Inst., Daimler‐Chrysler, Siemens), PolyGuide (Dupont, HP), TOPCat (NIST, 3M, Goodyear), Truemode™ (Terahertz), NTT and JIEP.