21 Jul 2006
Tampere in the west of Finland is renowned for being a centre of research and industry. Jacqueline Hewett visited the city to find out why its photonics industry is flourishing.
Tampere in Finland is a hub for the country's photonics industry and is thriving thanks to the close links between academia and industry. Not only does the city boast an eminent research facility in the form of the Optoelectronics Research Centre (ORC), it is also home to a number of start-up firms who have successfully transferred research from the ORC into commercially viable products.
Particular specialities of the region are diode lasers - including everything from the fabrication of the compound semiconductor material right through to the packaging of the final device – and ultrafast high-power fibre lasers.
These two areas have boomed thanks to the ORC's focus on semiconductor physics as well as ultrafast and intense optics (see "Activity at the Optoelectronics Research Centre") combined with an investment of over €16 m in scientific equipment. Although the ORC is keen to advance both basic and applied research, it is clear that employees have their eyes open for work with commercial potential.
The area surrounding the ORC is home to Coherent Finland, Modulight, Corelase, EpiCrystals and Reflekron. All of these companies are at different stages of development but fall broadly into two categories: those that concentrate on diode lasers and those that focus on fibre lasers.
Markus Pessa, the director of the ORC, told OLE that the total revenue from these five firms amounted to around €17 m in 2005. "I expect this to rise to between €20 m and €23 m in 2006 and in the region of €40 -50 m by 2010," he added.
ORC spin-offs: diode lasers
The oldest spin-off from the ORC, Tutcore, is now the Finnish arm of Coherent and specializes in epi wafers and laser applications. Tutcore was founded in 1991 and Coherent bought 80% of the shares in 1996 before acquiring the remainder in 1998. Today Coherent Finland employs 57 people and recorded a revenue of €15 m in fiscal 2005.
"We start with 2- and 3-inch GaAs substrates and have four MBE reactors in-house to do the front-end processing," Ilkka Tiainen, managing director of Coherent Finland, told OLE. "Some of the back-end processing such as coating and cleaving is then done here in Finland and some in California, US. We can grow a variety of III–V materials right through to producing packaged sources emitting from 600 to 1500 nm in-house."
In 2005, Coherent Finland donated a V90-type MBE reactor to the ORC, bringing the number at the centre to six and the total number in the Tampere region to 11. "Students need to understand the limits and capabilities of production tools," said Tiainen. "It is important that postgraduate education provides a readiness to work in production. This donation will help build that link between university and industry."
To survive the telecoms downturn, Coherent had to find new applications and customer segments and the answer was the graphic arts market. "We are not going back to telecoms - even if the market comes back," said Tiainen.
One firm continuing to produce diodes for certain telecoms applications is Modulight. Founded in 2000, it employs 22 people and is headquartered in a 32,000 ft2 facility that also houses a class 100 cleanroom. In February 2005, the company opened an office in the San Francisco Bay area, US.
Modulight's products are divided into three lines: high-power lasers, transmitter lasers and custom products and services. "We provide 6xx, 8xx, 9xx and 15xx nm lasers emitting powers between 150 mW and 150 W for the industrial, medical and defence/space markets," Petteri Uusimaa, president and CEO of Modulight, told OLE. "For example, we have a 15xx nm pulsed laser diode that is used for range-finding and our 6xx nm lasers find uses in medical markets. Other high-power applications include welding, marking, reprographics and spectroscopy. We also believe that our €95 nm unmounted quasi-continuous-wave bars will find a fit in the markets."
Turning to transmitter lasers, Uusimaa explains that these devices are used in the telecom/datacom, CATV and space markets. "Our target applications include short-reach 10 Gbit/s Ethernet, optical-time-domain reflectometers, intra-satellite communication and RF-over-fibre," he said.
One of Modulight's custom applications is to develop narrow linewidth lasers for the European Space Agency (ESA) to use in atomic clocks on satellites. Having secured a $364,000 (€286,000) contract from the ESA in May 2006, Modulight is producing a compact 894 nm DFB laser that can survive the harsh environment both at launch and in space.
According to Uusimaa, Modulight's business is roughly split into 40% high-power lasers, 40% transmitter lasers and 20% from custom products. "Our main markets are the commercial high-power market and selected telecom markets," he said.
Fellow ORC spin-off EpiCrystals is developing novel semiconductor laser components for medical and industrial applications. Founded in April 2003, the firm closed its first round of venture capital funding in April 2004 and is looking to raise a second round this year to help purchase equipment and factory space.
"EpiCrystals' core competence is laser wafer fabrication using conventional and new semiconductor materials," company CEO Tomi Jouhti told OLE. "We have a strong emphasis on next-generation edge-emitting and vertical cavity lasers and participate in two EU FP6 research projects, one of which is NATAL."
Jouhti explains that EpiCrystals is working on a family of high-power diode lasers that emit between 6xx and 12xx nm. These can be supplied as discrete chips, chips on C-mounts or bars. "We also have several R&D projects ongoing, one with an American and three with Japanese customers," Jouhti added. Although unable to give details at this time, Jouhti hinted that another product platform was in the pipeline.
ORC spin-offs: fibre lasers
The success of spin-offs commercializing the ORC's semiconductor physics research is mirrored by those working on fibre lasers. Corelase, which was founded in 2003 by former Coherent Finland employees, is focusing on three main product families.
The first product family is a fibre-coupled laser-diode pump array module (PAM) that is ideal for pumping and direct diode materials processing. The second product family is a direct diode laser system called D-LASE for soldering, welding and heat treatment.
"Our third product family is an ultrashort pulsed fibre laser, X-LASE, for micromachining and depositing thin-films," said Corelase's managing director Harry Asonen. "Our new product, the X-LASE 20-5, emits 20 ps pulses at repetition rates between 1 and 4 MHz. Average output power is a maximum of 20 W and pulse energy is a maximum of 5 µJ."
Corelase has used the X-LASE for a range of micromachining applications such as structuring ITO on glass and polymer and cutting grooves in cylinder steel, dielectrics and PMMA fibres. "Picosecond pulses allow you to process material with minimal thermal effects, a process known as cold ablation," explained Asonen. "Low pulse energies ensure high-quality cutting whilst high repetition rates lead to rapid processing speeds."
As well as removing material, the X-LASE can add material in the form of thin-film coatings. "X-LASE is a flexible way to deposit thin-films such as diamond-like carbon and TiO2 at room temperature," said Asonen. "This process can deposit a hard, scratch-resistant protective coating on a mobile phone screen or on spectacle lenses, for example."
The youngest spin-off from the ORC is a company called Reflekron, which has just celebrated its first birthday. "Thanks to several research projects that we carried out at ORC during the last six years, we have developed the knowledge to produce SESAMs for fibre lasers," Mircea Guina, managing director of Reflekron told OLE. "We realized that there was room for a company that specializes in both ultrafast semiconductors and fibre lasers. We started at 1.55 µm but now our primary focus is 1 µm sources."
The team behind Reflekron has been working in partnership with ultrafast fibre laser expert Fianium, supplying components for the UK-based firm to build into products. Starting with a compact oscillator, Guina explains that there are many end results such as high-power amplifiers, supercontinuum sources and using frequency conversion to access the ultraviolet. As well as acting as a component supplier, Reflekron is also involved in early stage fibre laser development. "We are continuously looking to identify niche applications where our expertise could provide competitive advantages. For example, we can do custom SESAMs for Q-switched microchip lasers," said Guina. "These require a completely different set of characteristics compared with mode-locked lasers."