30 June 2020
VIGO develops its first VCSEL epiwafers
VIGO System S.A. of Ożarów Mazowiecki, Poland (which manufactures photodetector, edge-emitting laser and transistor epitaxial wafers) has expanded its product portfolio to new epi-structures for vertical-cavity surface-emitting lasers (VCSELs). The firm says that it has developed its first VCSEL (the first to be manufactured in Poland) in order to demonstrate its capability for meeting increasing customer demands for disruptive epiwafer technology.
With optical power >4mW, low threshold current of 0.6mA and appropriate spectra characteristics, the 850nm VCSEL epi-structure is suitable for telecom and datacom optical applications.
Compared with other infrared technologies, VCSELs offer a highly efficient optical beam, excellent focusing and a very small footprint. Because they emit light perpendicular to the top surface, a VCSEL chip can be integrated into a single, two-dimensional array, consisting of several hundred individual apertures.
So, in addition to communication systems, applications for VCSEL products include light detection & ranging (LiDAR), printers, time-of-flight (ToF) sensors, autonomous vehicles (AVs), robots and drones.
The laser device was fabricated within the project ‘The technology of the production of innovative epitaxial structures and VCSELs’ as part of the national program ‘Pathway for Mazowsze’ (‘Ścieżka dla Mazowsza’). The project consortium includes VIGO System (as project coordinator), Lodz University of Technology, and Warsaw University of Technology.
Wlodek Strupinski, head of VIGO’s Epitaxy Division, was responsible for development of the epitaxial technology, VIGO’s Marcin Gębski for device processing, and professor Tomasz Czyszanowski of Lodz University of Technology for the laser design. Elements of the processing technology were also verified at Poland’s Institute of Electron Technology (ITE).
“We have been able to launch the production of this complicated structure in just less than six months after starting up the newly purchased [Aixtron] AIX 2800G4 [metal-organic chemical vapor deposition] system,” says Strupinski. “One of the greatest challenges was to achieve extremely high precision – with a single-nanometer accuracy – in layer thickness control (cavity, DBRs, MQWs) in order to rightly position the resonance dip, as required by demanding telecom applications,” he adds. “The whole epi-structure is about 7μm thick (which is regarded quite thick) and it consists of more than 200 layers.”
Following the launch of its first VCSEL epiwafer, VIGO intends to increase the production of VCSEL epiwafers as well as other innovative epi-structures.
“This is another future technology that VIGO System is adding to its product line,” notes CEO Adam Piotrowski. “The production of III-V compound semiconductor epitaxial structures for VCSELs and other photonic and microelectronic devices will enable us to further drive long-term profitable growth.”