The PCB industry

By froa0112 Mar 15th, 2009

The PCB industry

The PCB industry consists of the companies that are in the business of designing, manufacturing and marketing printed circuit boards for all sorts of applications. As a subsegment of the global microelectronics industry it accounts for some US$20 billion dollars in yearly revenue. Most of the high volume manufacturing sites are located offshore in the Far East countries, with a tendency to concentrate in cheap labor countries like China, Indonesia, Phillipines and Taiwan.

The Electronic Industries Alliance is a coalition of all of the branches of the Industry. Good place to look for contacts, customers or suppliers.

There are high barriers to entry in this industry as the capital expeditures required to compete efficiently and win businesses are very significant. Pricing has become dominated mostly by materials (many of which are oil derived and therefore subject to continuous increases), labor (therefore the almost stampede-like move to cheap labor countries) and cycle times (driven by access to high volume tools that require very high capital expeditures).

One place to start looking at the modern microelectronics industry, how healthy it is, what trends are shaping up and in general to gain a good understanding of the opportunities available is Las Vegas in January: the international Consumer Electronics Show

On the demand side, the cyclic nature of the global microelectronics industry, creates a double issue for sustainability of the PCB manufacturers: on one side, consumers expect electronic products to have a downward pricing trend, OEMs transfer these requirements to their suppliers, in an effort to remain competitive and viable in the market place, trying to squeeze every penny available. This limits margins for manufacturers and puts a continuous strain on these organizations to look for cost savings opportunities.

On the other side, short product life cycles for most products are typical (commonly referred as Moore's Law) and in the order of months for some applications, specially in the highly competitive handset market. This obviously requires aggressive asset utilization strategies and leverage to be able to return investment.

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Design:

Most design centers are part of the OEM or the EMS company, also most PCB manufacturers have their own internal design capabilities that can be brought to bear if the customer wants to save. Independent design houses are not easy to find as they are not competitive Some examples of independent design houses are:

Express PCB

Cadence can help with design software

PCB 123

Expert PCB

Materials:

moorelaw

The picture shows some of the basic components of a PCB board:

1. Organic resin: this is a polymer, or long chain of carbon atoms mostly forming the backbone that provides most of the mechanical and some electrical and thermal properties to the laminate. It typically accounts for 40-60% of the total weight of the substrate. Suppliers are chemical producers such the likes of DuPont, Shell, Dow, etc.

2. Inorganic filler: Small particles added to the resin to enhance its mechanical properties while allowing less use of the costly material. Many materials are used here, like talc, silica, clay, calcium carbonate, etc. Their selection depending on the specific application. A new class of materials is coming strong in this area: nanoparticles, made with the same raw chemicals but with novedous techniques that allow tremendous size reduction and property enhancement. Here suppliers are companies like Akzo Nobel, Hazcle,

moorelaw

3. Copper: the element directly responsible for electrical properties. Typically deposited as thin film by electrochemical techniques. Copper is mined and processed into bars, ingots or copper sulfate, which is the basic material used in the deposition baths.

Equipment:

To produce PCBs cost efficiently and at the economies of scale that make these ventures viable, requires complex infrastructure, a great deal of automation and significant investments.

One of the most fundamental requirements of this industry are clean rooms: virtually all photosensitive resist exposure and development is done in clean rooms. The reason should be obvious: even a hair diameter is greater that many of the dimensions of traces and vias in a design, averaging 100 microns. Dust, fibers, particles of every nature, all conspire against yield and reliability. To counter these, specially designed rooms where laminar flow is prevalent and extremely fine filters maintain particle concentrations to specified conditions have been developed. The typical specs are shown below (typical clean room classes):

equipment

Next up is the specific equipment used to fabricate the boards. As we said elsewhere, the basic laminate core comes prefabricated and coated from specialty shops like Isola, DuPont, etc. with brand names like FR4 (Fire Retardant NEMA Grade 4 Laminate), BT (Bismaleimide Triazine).

What's left to do is to expose, develop and plate film. There in average 78 individual steps per build up layer. So it's easy to see that cost goes up quickly for complex designs requiring multilayered PCBs.

Automated equipment for board fabrication.