Keeping the innovation streak going, while maintaining and improving reliability

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Building resilience into the handset designs of the future


Dr Nick Rimmer, VP – Technology and Product Strategies at P2i

After years of standing still and identikit aesthetics, 2017 was a positive year for smartphones.

There were plenty of varied designs and more visually striking devices than ever before, with more phones using curved and bezel-less displays. With numerous innovative designs taking the stage at this year’s Mobile World Congress in Barcelona, the future looks bright, and things are only going to get better for consumers, manufacturers and engineers alike.

Recent GSMA figures show that the number of people connected to mobile services surpassed five billion globally last year, with two out of three people in the world having a mobile subscription at the end of 2017. Improvements in global connectivity, fostered by more advanced mobile networks and growth in the global subscriber base, means that mobile design is finally being pushed to the limits of what is possible today. Powerful emerging technologies are being democratised, increasing consumer choice and diversifying the mobile market.

Take bezel-less displays. Once the preserve of high-end flagship devices, these will trickle down to be included in more affordable mid-range handsets. Flexible screens, pioneering camera technology and elegant USB-C connections are all being utilised and will increasingly become commonplace features.

Keeping the innovation streak going, while maintaining and improving reliability

But as exciting as new features and technologies are, there are inherent risks associated with adding complexity to the hardware deployed in smartphones. Namely, how do you protect the more complex internal workings of a smartphone from everyday wear and tear, as well as the environment?

Liquid ingress, for example, is a significant factor in the millions of smartphones that are damaged beyond repair each year. Today’s consumers expect to be always connected, so any threats to connectivity need to be mitigated as standard. But the mechanical gaskets and seals often used by manufacturers to protect against liquid ingress can also place limits on handset design.

With more and more devices being deployed with USB-C connector systems, the amount of damage that can be caused by water ingress can be significant. Pin density is almost double what it is on older USB ports, with pins that are smaller and closer together, giving rise to an increased risk of short circuit in the presence of water.

Water ingress via USB-Cs, which are capable of carrying 20 volts and 5 amps of current, can result in instantaneous and catastrophic corrosion. Even if circuit breakers kick-in to shut a smartphone down, users are then left with a device they can’t use at all in the short term, and one that will require some immediate attention to assess long term damage.

Newer build techniques and components have also made the process of repairing a smartphone harder. Devices with OLED screens – found on the likes of the iPhone X – can be incredibly tricky to dismantle because of the adhesive that is used, and the repair process can risk further damage when carried out. So even if a broken screen has nothing to do with water damage, the process of repairing it can easily compromise the gaskets and seals designed to protect devices against water ingress.

Following the rise in consumer expectations and increase in market demand for ground-breaking design, functionality, and reliability, more and more handset manufacturers are now turning to hydrophobic nano coating solutions to better protect smartphones, regardless of the components used in their design.

The growing case for nano coating tech

Unsurprisingly, the market for nano coating tech is booming. Zion Market Research indicated last year that demand for waterproofing and, specifically, for nano coating technologies from the electronics industry is going to grow rapidly over the next two years, with the global market for nano coating projected to be worth $6.85 billion by 2020.

Many premium OEMs are currently working on the problem of water resistance by using both hydrophobic coatings as well as gaskets and seals in their products. However, as the level of protection provided by nano coatings increases, it’s likely that innovative manufacturers will bypass physical barriers altogether. This will allow them to use cost effective alternatives to mechanical solutions that don’t restrict their aspirational designs.

How does nano coating technology work?

Nano coating differs from more traditional waterproofing solutions, in which physical seals are built into devices to stop water ingress. They are applied through a low-pressure plasma deposition process that coats the device inside and out with a nano-scale polymer chemically bonded to the surface.

The nano coating can be applied at the end of a production cycle, but increasingly manufacturers are integrating it at multiple stages of the production process. Crucially for the smartphone market, nano coating also enables greater design freedom than physical gaskets and seals.

Rogue traders

Unfortunately, not all nano coatings are created equal and nor do all solution providers operate to the same standards. We’ve already talked about type-C USB connectors, but they are worth a closer look to illustrate the point. As is standard practice, OEMs will typically use 2-4 suppliers for this type of component. Most components are of an adequate standard, but others may use lower grade materials, which leads to more frequent component failures. This kind of problem is not one which can be solved by the application of a nano coating, as the problem lies within the connector.

The conductive surfaces on high quality USB-C components are made of gold and don’t require a nanocoating, although the components inside the device that they are connected to will. But those made using inferior quality gold-plate have been seen to corrode from the inside out and, depending on the nano coating solution offered, could render a device with a degraded level of protection at the point of most vulnerability in a device.

Today, some providers are offering solutions to protect USB-C connectors that are little more than fool’s gold. A coating is not necessary to protect premium quality USB-Cs and can’t protect inferior products.

To ensure reliable and consistent protection, manufacturers need to work with nano coating technology providers who are open and transparent about their products’ capabilities and offer clear consultancy on which component suppliers and materials they should be using.

Evolving capabilities

In the future, we expect to see OEMs start to build in early warning systems to their handsets that alert users to water ingress. The Liquid Detection Indicators (LDIs) that are currently commonly used are only exposed when a device has already starting malfunctioning and is sent off for repair – particularly in devices with built-in batteries.

Humidity sensors and voltage regulators could better detect and alert users in real-time to water ingress, enabling them to dry out their smartphone, or get the seal that has been damaged repaired. This is only possible though when a device is protected by a hydrophobic coating, because once water has bypassed a physical seal and found its way to an unprotected Printed Circuit Board (PCB), the corrosion will start immediately.

Consumers want to own and manufacturers want to build handsets that push the boundaries of design and are aesthetically impressive. But the functionality and reliability of these devices is also important due to our increased reliance on them for everyday tasks in our work and personal lives. Nano coating technologies provide a way for OEMs to tick all of these boxes and create devices that will revolutionise the smartphone market.

Components in Electronics – P2i  May 2018