IN Brief:
- Polar Light and Foxconn have agreed to investigate pyramidal microLED technology for optical interconnects.
- The initial work focuses on 5 µm green InGaN emitters produced through Polar Light's Swedish pilot line.
- The company reports reduced piezoelectric effects and demonstrated CMOS integration, but has not disclosed interconnect data rates.
Polar Light Technologies has signed an agreement with Foxconn Technology to investigate the use of pyramidal microLED emitters in optical interconnects for data centres and high-performance computing systems.
The Swedish semiconductor developer will initially focus on green microLEDs measuring 5 µm, corresponding to devices already being produced through its manufacturing pilot line. Announced on 12 November 2026, the agreement represents Polar Light's first formal cooperation programme targeting optical interconnects rather than display applications.
Optical interconnects transmit information using light, providing an alternative to electrical signalling over copper connections. The approach is being developed for computing architectures in which increasing data rates, communication density, and power requirements create constraints on conventional electrical connections between processing and networking components.
At high data rates, electrical interconnects must manage attenuation, reflections, crosstalk, and other signal integrity effects. Signal conditioning can compensate for some of these limitations, but introduces additional circuit complexity and power consumption. Optical transmission can move the communication path into a different physical medium, although it introduces requirements for light generation, optical coupling, detection, and associated electronics.
Polar Light's technology uses indium gallium nitride semiconductor structures grown into microscopic pyramids. The company employs a bottom-up fabrication approach in which the pyramidal geometry is formed during semiconductor growth rather than defined through the etching processes commonly used to separate individual emitters.
The architecture has principally been developed for microLED displays, where individual emitters must be manufactured at high density and integrated with electronic circuitry. Polar Light has also demonstrated the integration of its pyramidal structures with CMOS backplanes, establishing a route for combining the emitters with the circuits needed to control them.
Optical communication places different demands on the same semiconductor architecture. A display pixel must produce the intended brightness and colour within a visual system, while an optical transmitter must respond rapidly and predictably to changes in its electrical drive signal. Modulation speed, optical output, coupling efficiency, and long-term stability consequently become important device characteristics.
The company's pyramidal design reduces the influence of strain-related piezoelectric fields within the InGaN structure. Polar Light reports a 40% reduction in this effect compared with conventional planar InGaN LEDs, a characteristic associated with faster carrier recombination and shorter emission decay times.
Internal electric fields in an InGaN emitter influence the spatial relationship between electrons and holes. Their behaviour affects the rate at which carriers recombine and release photons, which in turn can limit how quickly the optical output follows changes in the electrical input. Reducing the internal field provides a possible route towards faster modulation.
The reported improvement is a semiconductor device characteristic rather than a measured data rate for the proposed interconnect. Polar Light and Foxconn have not disclosed an operational transmission link, modulation bandwidth, bit-error rate, or energy consumption per transmitted bit. Those measurements will be necessary to establish whether the device-level advantages translate into a useful communications system.
Polar Light also identifies the emission pattern of its pyramidal microLEDs as relevant to optical coupling. The company describes a Lambertian light distribution, in which emission intensity varies with angle rather than being concentrated into a narrow beam.
The efficiency with which this light enters an optical fibre or waveguide will depend on the complete coupling arrangement, including emitter dimensions, numerical aperture, alignment, and any additional optical structures. A favourable emitter geometry does not remove the need to manage coupling losses and mechanical tolerances within the finished assembly.
CMOS integration provides another development route. Combining light emitters with silicon-based electronics could allow the drive circuitry to be positioned close to the optical source, reducing some external connections and supporting compact emitter arrays. The electrical design must nevertheless account for switching speed, drive current, heat generation, and interference between adjacent channels.
High-density arrays introduce further manufacturing requirements because individual optical channels must deliver sufficiently consistent characteristics. Variations in emitter dimensions, output intensity, and electrical response may require calibration or adjustments within the associated drive electronics. Production testing will also need to identify defective or marginal devices before they are incorporated into larger optical assemblies.
Foxconn Technology's participation provides an industrial partner for investigating the integration of these emitters into information and communications technology hardware. The agreement does not identify a particular processor, accelerator, networking platform, or customer system that will adopt the technology.
The collaboration also creates a second potential application for Polar Light's semiconductor manufacturing work. Its pilot line already produces green emitters in the size range selected for the optical interconnect programme, although manufacturing devices for evaluation is distinct from qualifying a complete communications product for volume deployment.
Future development will need to establish repeatable optical modulation performance, coupling efficiency, operating temperature limits, and reliability under continuous use. The companies have not announced engineering qualification dates, production commitments, or commercial availability for an optical interconnect product.
The initial programme will evaluate whether Polar Light's 5 µm green microLEDs can satisfy the optical and electrical requirements of high-density communication links. Demonstrated link-level performance, rather than emitter dimensions alone, will determine the technology's suitability for future computing platforms.
