Plessey Semiconductors

  • Established 2009 (earlier company started in 1957)
  • Head Office Plymouth
  • Employees 165
  • Plessey ownership
    Ownership: Venture capital companies, Michael LeGoff
  • 2015 Sales £10.5m

Scientific breakthroughs make possible a new generation of light sources

The long journey to creating a force in semiconductors

The evolution of Plessey Semiconductors goes back almost a century, during which there have been many twists and turns in the story of what was once a mighty UK manufacturer.

  • Plessey starts in London as a mechanical engineering company
  • Plymouth plant built
  • GEC of the UK and Germany’s Siemens acquire Plessey, valuing company at £1.75bn, and split the operations, with GEC taking semiconductors including plants in Plymouth and Lincoln
  • Michael LeGoff founds Dynex in Canada , a distributor of power semiconductors, used in mobile phones
  • GEC-Plessey Semiconductor acquired by Mitel of Canada
  • LeGoff’s Dynex buys Lincoln semiconductor plant from Mitel
  • X-Fab of Germany buys the Plymouth plant
  • LeGoff leaves Dynex, which is sold to CSR of China in 2006
  • LeGoff buys the Plessey semiconductor assets in Swindon
  • LeGoff buys Plessey’s Plymouth plant and bases the company there. The Swindon operation closes
  • Plessey announces a £60m expansion, based on new venture capital investment and a £30m loan from Deutsche Bank

Engineering innovator sets out his goals

Michael LeGoff has ambitious targets for the company he has created. Plessey’s chief executive wants the business to generate sales of more than £100m by 2018, a near-tenfold increase on the 2015 total. Most of this would come from the company’s new families of LEDs.

“I think we can do this,” LeGoff says. “You can compete on cost here [in Britain] and the engineering talent pool is extremely strong.”

LeGoff says he will be helped by up to £60m of investment in the company – much of this coming from the two unnamed venture capital businesses which are the majority owners, while Deutsche Bank is providing a £30m loan. The money is paying for new equipment that will enable a big jump in output.

Plessey’s current 165-strong workforce is set to triple by the end of the decade when the company hopes to export 90 per cent of its production to the world’s top lighting manufacturers.

LeGoff bases his plans on extensive experience in the electronics industry. After a spell as an engineer in the Canadian Navy, in 1995 he set up a company of his own in Canada, first distributing power semiconductors and eventually moving into manufacturing them himself. This was Dynex, which listed on the Toronto stock exchange in 1998 and two years later bought a British semiconductor plant in Lincoln that had once belonged to “old Plessey” and was now surplus to the requirements of its current owner, the Canadian company Mitel.

He left Dynex in 2005, a year before it was sold to CSR of China. He then spent several years scouting for new opportunities before acquiring the rights to the former semiconductor operations of Plessey in 2009. A year later LeGoff shifted the manufacturing and administrative activities to Plymouth, where Plessey already had a semiconductor plant.

A big part of LeGoff’s strategy is forming relationship with major producers of lighting fixtures such as GE Lighting, Acuity and Aurora of the US, China’s Feilo-Sylvania, Zumtobel of Austria and Switzerland’s Regent.

Britain’s unhappy history in electronics production

Britain has a proud record of innovations in electronics – but has done a poor job of turning these into sustainable businesses that create large numbers of jobs.

After World War Two, UK engineers built some of the world’s first electronic computers, among them Cambridge University’s EDSAC machine (electronic delay storage automatic calculator) which was completed in 1949.

In the 1970s, the UK was responsible for three of the world’s leading electronics companies: Plessey, GEC and the computer manufacturer ICL. In the 1980s, Ferranti, another pioneering UK firm, was responsible for a number of innovations including so-called gate-array chips – a form of “customised” or “application-specific” semiconductor.

Now that these one-time electronics leaders have all disappeared, UK electronics manufacturing is represented mainly by a few sophisticated companies turning out mainly small quantities of high-value products on behalf of bigger businesses on an “outsourcing” basis.

Such “contract manufacturers” include Briton and Paragon, both based in Bedford, and US-owned Plexus, which operates a plant in Bathgate, Scotland. Such companies make products such as medical devices or control equipment, normally sold under other companies’ brands.

Besides Plessey, Britain is home to a handful of other semiconductor manufacturers. One of the few UK-owned businesses is Semefab, based in Glenrothes, Scotland. Infineon of Germany operates a plant at Newport in South Wales, while NXP of the Netherlands makes chips in Stockport, near Manchester.

The area in and around Cambridge has a notable “cluster” of small electronics businesses, many with links to Cambridge University. Bristol and nearby towns are home to about 30 electronics firms – many of which were set up or staffed by skilled engineers and technicians who at one time worked for Inmos, a state-owned semiconductor business started in the city in 1978.

Inmos was responsible for a number of technology successes – including the “transputer” microprocessor. But it failed to meet its commercial targets and was privatised in 1984, disappearing from view a few years later.

The making of a mass-customised chip

One of Plessey Semiconductor’s key technology breakthroughs is its development of what amount to “application-specific LEDs”.

These are based on standard electronic cells but in the final stage of production they are customised for specific purposes. Plessey Semiconductor’s ability to customise LEDs in this way enables the large lighting manufacturers it supplies to avoid having to tailor their light fittings to suit many different uses.

Normally, if an LED is going into a domestic lamp, it will require a different light fitting – or luminaire – than if it were going into a traffic signal or a hospital operating theatre.

“At present, the systems manufacturer has to struggle with creating hundreds if not thousands of different luminaires so that the final product will work as intended. With the Plessey process, we will be able to configure the LED chip to suit the application before it leaves the factory, simplifying the overall manufacturing procedure and reducing costs,” says Michael LeGoff, Plessey’s chief executive.

In essence, responsibility for the key job of ensuring compatibility between the semiconductor and its final use has been switched from the customer to the supplier. Plessey hopes the breakthrough will give it an important advantage.

Plessey Semiconductor was helped in the development of its application-specific LEDs by its 2011 acquisition of CamGaN, a company spun out of Cambridge University.

The Plessey process is based on gallium nitride, which has to be fused on to a base layer made from silicon, the key material used in making most semiconductors. In most comparable LEDs, the base layer is sapphire, a form of single-crystal alumina. Sapphire is more expensive than silicon and more difficult to process – limiting the applications for sapphire-based devices and making them more expensive.