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34 The PCB Magazine • June 2017 typical processes: mechanical drilling, mechan- ical and chemical milling, routing, photoimag- ing, screen printing, electroless and electroplat- ing of different metals, and etching. These are considered as the enabling steps to produce a wide range of products. As a result, many in- novative solutions are offered for various in- dustries such as automotive and industrial elec- tronics, lighting technology, measurement and medical technology, as well as the home auto- mation sector. The following typical products are manufac- tured: • Conventional printed circuit boards (PCBs) • Active Multi Layer (AML) • Active and passive front plates • Printed board assemblies • Metal core substrates (MCPCB or IMS) • Printed circuit boards with embedded components • Mechanical components and mechatronics • Conventional front panel applications, front panels with integrated components (intelligent front panel) The Trend in Device Embedding Technology Embedding of passive components has been used in ceramic hybrid circuits since this tech- nology was introduced in the beginning of the 1970s. Polymer thick film paste was used. Oh- megaPly® a resistor foil was available for PCBs as well. However, in mass production, only hy- brid circuits are used. From the material point of view, this is an expensive technology selec- tion. In cases where it is needed for reliability reasons, the higher cost has been justified. In mass production, the industry is looking for a more cost-effective solution based on organic PCB technology. Here the PCB fabrication tech- nology has a clear advantage. Large panel pro- duction and standard multilayer processes offer an outstanding technology basis for embedding active and or passive components in the organ- ic FR-4 material. As technology has evolved, smaller compo- nents made it easier to embed active and or pas- sive components inside of PCBs by using the stan- dards soldering or other component attachment technologies like gluing, sintering or plating. In 2011, the integration of embedded con- nector was evaluated by Hofmann Leiterplat- ten in Germany and introduced in the standard production of the latest design for device em- bedded technology. Examples are shown in Fig- ures 16, 18 and 19. The Process for Fabricating Device Embedding Technology PCBs The surface mount device technology was an enabling way to place SMD parts on the sur- face of FR-4 CCL material on solder land layer of the PCB. This was then the important step to take the surface mount components to the in- side of printed circuit boards (Figure 3, Step 1). For this process, a thin core CCL (0.36 mm) is used for mechanical stiffness during com- ponent placement. Thinner FR-4.0 and FR-4.1 laminate can be used. In our company, we have experience with both brominated flame retar- dant that is used in FR-4.0 and the different flame retardant that are used in FR-4.1. We have gained experience with the resin flow, press condition and curing behavior of the important resin systems used in FR-4.0 and FR-4.1 CCL. By placing the components inside the PCB, the electronic components and the conductors are better protected against mechanical damage, shock, dust impact and the influence of humidi- ty and of any liquids like water, cleaning agents, solvents, oil and others liquids that could dam- EMBEDDING ACTIVE AND PASSIVE COMPONENTS IN ORGANIC PCBS Figure 1: View of the factory—28 years of quality made in Regensburg.