Global work on flexible printed electronics gives smart design and pushes photonics

The rigid electronic printed circuit boards will not in future restrict new product design and will in fact enable the manufacture of an entirely new portfolio of products according to the Technical Research Centre of Finland (VTT).  Design of new products, as the manufacturing develops towards flexible, design-friendly and inexpensive form of electronics, and  new manufacturing methods will change production processes enabling the manufacturing of entirely new product types. VTT sees a bright future in printable and plastic-based electronics and is investing in the research in this area.

Major progress is being made in printed electronics and material research, which will allow the introduction of new electronics manufacturing methods and products. Electronic products differing  substantially from their current features will be launched into the markets in a few years.
                                                                                                                                                                                                                                     3D RF fictional module: VTT

Future applications employing plastic-based electronics will include mobile phones and electronic appliances for home and the automotive industry. By integrating sensors, light sources and light guides, new product types will include lighting and decoration and electronics introduced into everyday products. An example could be a spoon that automatically measures the weight and temperature of it's content.

Smart spoon a VTT's product concept, combines printed electronics and film over mold - measures weight and temperature. The plastic handle has sensors and integrated screen and a photocell as power source

Simple applications can already be manufactured, but it will take five to ten years before more complex devices can be introduced to markets. Electronic products will be designed more freely as the PCBs become printed on flexible foils. The end product will be partly or entirely flexible, streamlined and better address the user's needs.
By printing electronics circuits on plastic film, it is possible to cut down manufacturing cost and use more environmentally friendly manufacturing methods than currently in the production PCBs.

VTT is developing a plastic-based electronics manufacturing technology that will combine research activities in optics, mechanics and printed electronics. Electronic circuits and components are being integrated into plastic mouldings to reduce the total number of device components, lower assembly costs and improve product durability.  This integration will also reduce appliances size, absorbing empty space. Combined manufacturing of printed electronics and injection moulding, are particularly suited for applications where manufacturing volumes are large.

The European electronics industry must specialise to
survive increasingly keen global competition, as
electronics manufacturing is moved to countries with
lower labour costs. Plastic-based electronics technology can be developed into a next-generation manufacturing paradigm, that will simultaneously use of established expertise and machines and the opportunities offered by new technology.

Methods that combine injection moulding and printing are highly cost-effective but call for broad technical planning and expertise, which makes the copying of  these products difficult. In fact, VTT feels that the European electronics industry could fight the China phenomenon by developing electronics manufacturing clusters that gather state-of-the-art expertise and specialise in a limited field of applications.
                                                                            Experimental  PCB with electronic components and film over mold: VTT

The combination of injection moulding technologies with printed electronics is being investigated in VTT's
self-funded SIPS project, which is part of a  Complex Systems Design theme.

Flexible optical PCB developed in Korea
The Korea Photonics Technology Institute (KOPTI) has developed the world's first flexible optical printed circuit boards (PCB) for a variety of mobile applications. The next-generation PCBs are capable of transmitting both electricity and optical signals simultaneously. With high-speed signal transmission at data rates of 100Gbps, the technology is expected to enable high-quality video conferencing applications.

According to KOPTI, unlike the existing optical PCBs which simply transfer optical signals, these newly developed flexible optical PCBs are connected using optical planar lightwave circuits (PLC). The PLCs are stacked on the flexible PCBs to enable transmission of both electricity and optical signals simultaneously.

An optical PCB is a connection system for transferring signals through an optical fiber line within the board using optical devices such as surface radiation lasers mounted on the board. While electrical PCBs deliver electrical signals through copper, the transmission medium for optical PCBs is the ultra-thin film's optical circuits that feature very low noise.

This hybrid technology overcomes the limitations of electrical PCBs on transmission capacity and signal quality, while enabling large capacity transmission at an ultra-high speed from several hundred Gbps up to Tbps. It is regarded as the next-generation technology to replace electrical routing with optical routing systems using optical PLCs between chips, boards and backplanes.

A flexible optical PCB is a manufactured substrate with optical PLCs inserted; flexible PCBs are commonly used in the hinges of notebook PCs, mobile phones and digital cameras. Flexible optical PCBs are required to undergo stringently repetitive winding tests for specific reliability specifications, which are not required for fixed optical PCBs.

As mobile terminals become more multi-functional and the capacities for data to transfer within these terminals increase, developers have struggled to develop next-generation connection technologies such as embedded PCBs and optical PCBs. KOPTI expects this technology to have a significant impact on to the PCB industry, especially in Korea.

Byung Sup Rho, manager of KOPTI's integrated optical module team, said, "These flexible optical PCBs can interactively transfer large-capacity multimedia data at gigabit rates while avoiding EMIs among routings, enabling designers to use core electronic components for mobile applications such as digital still cameras.

"As reliability is such a crucial issue in the technology, it is important to have standard compliances. A variety of tests such as the repetitive winding, heating and impact, and solder reflowing tests for electronic/optical device packaging should be implemented to obtain good reliability," he added.

KOPTI, established in Gwangju, is a research institution devoted exclusively to the development of photonics technologies. With photonics becoming a new knowledge asset and growth engine for the electronics industry, KOPTI will continue to contribute to the local photonics industry by strengthening its R&D capabilities.

Sources: http://www.vtt.fi/
Source:http://techon.nikkeibp.co.jp
Web: www.kopti.kr/