Intel has built a laser array using its 300-millimeter silicon photonics manufacturing process.
A silicon wafer-based, eight-wavelength DFB laser array with an output power uniformity of +/- 0.25 decibels (dB) and a wavelength spacing uniformity of 6.5 percent has been demonstrated by Intel Labs! This makes it possible to produce optical sources with the necessary performance for high-volume applications in the future, such as optical computation interconnect for developing network-intensive workloads like AI and ML and co-packaged optics.
Optical communications, an important area of study for Intel Labs, is a component of their integrated photonics work and involves three key components of their entire silicon-photonics effort. These core pieces include “a light source or a laser, as well as being able to modulate it,” says James Jaussi, senior principal engineer and director of Intel Labs’ PHY Research Lab.
“Another key piece is to amplify it, as well as to detect and receive the optical signal and convert it to an electrical signal on the CMOS chip. And the other key piece is CMOS electronics, which are used primarily to control or interface with the photonics—both in terms of modulation as well as detection and amplification within the electrical domain. These components are key to this vision, but what really brings this technology together is ability to integrate into a single package.”
Recent DWDM-based co-packaged optics technologies have showed the potential to increase bandwidth while considerably shrinking the size of photonic circuits. The production of DWDM light sources with consistent wavelength spacing and power has proven challenging. This innovation meets the criterion for optical compute connection and DWDM communication by ensuring consistent wavelength separation of light sources while keeping uniform output power.
Prior to the III-V wafer bonding procedure, Intel used advanced lithography to define the waveguide gratings in silicon for this study. When compared to conventional semiconductor lasers made in 3-inch or 4-inch III-V wafer fabs, this method produced improved wavelength uniformity.