With the ascent of Industry 4.0, the urgency of connecting to equipment on a manufacturing line is increasing. This article focuses on the electronics industry and summarizes what that interaction can entail, how it occurs, and the potential benefits. Interaction is broken into six areas: 1) automating transactions, 2) pulling data, 3 determining efficiency 4) sending settings/recipes, 5) dynamically changing settings and 6) applying machine learning. Seven communication techniques are also described: REST, SOAP, network socket, SECS/GEM, IPC Hermes and IPC CFX, and file transfer. Guidelines and current state-of-the-industry for each are given. Potential benefits for each are outlined along with suggested ways in which ROI can be calculated.

Within-application reliability and fail-safe processes paramount, aerospace applications present unique challenges for materials suppliers. As aerospace electronic devices increase in power density to accommodate higher function, and energy-efficient, high operating temperature wide bandgap (WBG) semiconductors become more prevalent, new materials with robust thermal management capabilities and higher operating temperature ranges are required.

Recently, a hybrid technology that marries the high thermal performance of pure silver sintering materials with the reliability of epoxy-based die attach pastes has been developed and is a promising solution to address these challenges. This hybrid technology offers similar electrical and thermal performance as sintering pastes but has exhibits less voiding and is process-friendly, much like that of traditional die attach pastes. This paper presents the results of an application study aimed at developing this unique technology in the field of high-power density devices for aerospace applications.

Conformal coatings are essential components for the microelectronics packaging industry. These functional coatings aim to protect electronic circuits from environmental factors such as heat and moisture. Typical coating formulations involve the use of epoxy, urethane and acrylic chemistries on polymer printed circuit boards (PCBs) leading to poor adhesion and failure to form void-free uniform coatings that follow the PCB skyline contour.

Plasma treatment is a novel method to increase the adhesion strength of the conformal protective coatings to PCBs through the removal of residual organic contaminants and surface activation. Poor adhesion can be a result of: i) incompatible materials, such as bonding polymers, ii) process residue: contaminants from fluxing, soldering and chemical treatments and iii) handling and storage conditions: fingerprints and dust. Plasma treatment under atmospheric pressure plasma (APP) conditions has emerged as an alternative solution for completely assembled PCBs which does not require a vacuum-based system. APP processes are fast and can be used for the treatment of selective areas of the board. The technology utilizes a dry gaseous medium and does not involve any harsh liquid solvent chemistries.  Air-based APPs contain gaseous species that can react and remove organic surface contaminants very rapidly.  Furthermore, they can be instrumental in the chemical functionalization and activation of the surface.  In this paper, case studies from the application of air-based APPs for the cleaning of PCBs and the improved adhesion of conformal coatings will be presented. 

The demand for smaller, faster and smarter electronic devices that can communicate to each other via wireless networks is stretching current communication systems to their limits. This rapid paced evolution is the driving force for the development of the next generation of network systems, the so-called 5G, to give the increased speed of communication and data capacity required.

One of the key factors, which will influence the development in 5G, is the range of frequencies at which data is transferred. Current 4G systems operate in relatively low frequencies of <6GHz. With the introduction of 5G systems, the requirement will be to run at much higher frequency band width; typical range will be from 6 up to >100GHz to enable faster mobile broadband, with low latency (the time taken for devices to respond to each other or a signal from another device) and the “internet of things” where compatible devices “talk to each other”.

With this transition to higher frequencies, the path of the electrical signal moves towards the edge of the copper traces into the so-called “skin” or the extreme outer edges of the copper trace. If this “skin” has been heavily roughened or etched, such as is the case in conventional multi-layer bonding enhancement processes, then there is an unacceptably high loss of the electrical signal.

To overcome this high signal loss material suppliers have been developing reliable high-speed dielectrics with low dissipation factors and dielectric constants. In combination with this, the contribution to signal loss from the bonding enhancement chemistry is under great scrutiny. Here, the challenge is to provide the most functionally reliable bonding process with the minimal surface roughening; but as the widely used Oxide Replacement bonding enhancement systems rely heavily upon surface roughening to give good bond strength this creates something of a challenge.

This paper highlights the challenges, developments and modifications made with conventional Sulphuric-Peroxide based Oxide Replacement bonding enhancement system to meet the low signal loss requirements for High Frequency applications, whilst maintaining the highest functional performance and bonding integrity needed for manufacture of reliable multi-layer PCB’s.

The migration to large panel substrates in advanced packaging applications is principally motivated by cost considerations. However, it is occurring at a time when package processing is becoming more complex and demanding. New package architectures featuring heterogeneous integration (HI), such as Intel's EMIB, TSMC's INFO, and many others, present challenging new requirements in the fabrication process. With feature sizes less than 10 microns, increasing number of patterned layers, and vias between layers, these demanding process steps must be realized on wafer and panel substrates alike.

The traditional equipment set for large panel substrates typically uses bulk processing and is not designed for wafer-like process requirements. Thus, a new class of process tool is required to bridge this technology gap, maintaining the economy of scale of large panel tools while meeting the requirements of current and future package architectures. For electroplating process steps, a vertical tool architecture running a single panel per process cell makes it possible to directly apply advanced wafer plating technology to panel substrates.

Individual panels are loaded in a rigid holder to minimize warpage and provide the large currents necessary for plating large areas. An overhead transport conveys the loaded panels to a series of cells which carry out the necessary steps in the deposition process. The initial step is a vacuum prewet, which prevents the occurrence of air bubbles in deep features when the panel is introduced into a plating bath. A series of plating cells allows a stack of different metals to be deposited in a single pass through the tool. Each cell is customized for a particular metal and, with features such as multiple anode zones and pattern-specific shields, can be customized for each device. Efficient agitation is also adapted from wafer plating tools to provide the fastest and best quality deposition processes.

This paper will show that the improvements in feature density, deposition uniformity and void free via filling that are required for heterogeneous integration can be achieved in large panel processing, providing the desired cost reduction relative to wafer processing for interposers and other package structures.

The electroless deposition of Copper is widely used within the printed circuit board industry as it offers a simple and reliable method for metallizing holes, which subsequently enable multilayer PCBs. While the process as a whole continues to develop since its adoption, one point that has remained common is the need to activate those materials on which the Copper does not naturally deposit, namely the glass fiber bundles and epoxy matrix. Such activation processes are typically based on Palladium as this has been long proven to be a reliable method, however its use does not come without some penalties. The activation step is acknowledged to be one, and in some cases, the most expensive step within the electroless Copper process as a whole, and this is due to the cost of the Palladium metal itself. Historically this has always been a concern, but with the current cost of Palladium exceeding that of Gold, the desire for a “low cost” activator has increased dramatically in recent years.

Over the years, many suppliers have developed alternative processes utilizing conductive polymers or variations of carbon, and while these have been accepted within the market and have generally been found to operate at a lower cost, with decades of reliability data, and countless installations worldwide, the metallization of through holes with electroless Copper remains the preferred method for many applications. Hence the need for a “low cost” but high performance, Palladium based activator step remains as strong as ever.

This paper summarizes experiences gained while developing a new cost effective Palladium containing ionic activation system, we review the successes and issues found with early generations and then show that building on these experiences, a successful, low Palladium activation system can be provided that satisfies both the technical and commercial demands of today’s PCB market.