Adoption of Silicon Photonics is Reaching an Inflection Point

发表时间:2020-08-31 15:48

June 4, 2020

LightCounting releases 6thedition ofIntegrated Optical Devices Report

Many in the industry have predicted thatsilicon photonics (SiP) will enable inexpensive, mass-produced opticalconnectivity, radically changing the optical components and modules industry.Forecasting the timing of such transitions is most challenging. Just like withmany other radical changes, nothing seems to happen for a while until suddenlythe change is here for everyone to see. We might be reaching such an inflectionpoint in adoption of SiP and transformation of our industry now.

Figure below shows our latest forecastfor optical transceivers, AOCs and EOMs, illustrating the growing share ofSiP-based products. It is projected to increase from 14% in 2018-2019 to 45% by2025, as the market returns to double digit growth over the next 5 years. Theindustry seems to be set for such a radical transition. The customers want itand suppliers are ready to deliver.

Figure: Global market for opticaltransceivers, AOCs and EOMs by technology

Why now? It took almost a decade for amajority of customers to warm up to SiP technology and recognize thelimitations of InP and GaAs optics in terms of speed, reliability andintegration with CMOS electronics. Massive adoption of optical enginesco-packaged with switching ASICs and FPGAs seems to be just around the corner.Even if it continues to be “just around the corner” for the next decade, thereare several optical transceivers on the market now, enabled by 2.5D and 3Dmulti-chip integration. Not all of these co-packaged chips are based on CMOStechnology, but the share of CMOS is growing, and this is impacting the opticsas well.

Acacia’s latest version of high-speedcoherent DWDM transceivers is a great example. It combines a SiP-based photonicintegrated circuit (PIC) with a CMOS-based DSP into a single 3D-stackedassembly, which also includes a modulator driver and TIA chips. The chips areinterconnected by vertical copper pillars, to reduce power losses on RFconnectors and increase speed. It is powered by an external narrow-linewidthtunable laser, which requires temperature stabilization, but the SiP-based PICworks fine in one stack with the hot ASIC.

The first 3D stacked design of anEthernet transceiver was introduced by Luxtera (now Cisco) a few years ago.2.5D integration combines multiple chips by placing them on a common substraterather than staking them vertically. This approach is more suitable forintegrating chips made of different materials, while offering similar benefitsof higher speed and lower power. However, the better performance andreliability of high-speed SiP-based modulators tilts the scale in favor of thistechnology for both 2.5D and 3D integration.

The first 400GbE transceivers, sold in2019-2020, use InP-based devices, but we expect that SiP-based 400GbE productswill gain share in 2021-2025. LightCounting’s list of TOP 10 transceiversuppliers included three switch vendors in 2019: Broadcom, Cisco and Intel. Allthese companies are committed to CMOS and SiP technologies and they will beamong the leading suppliers of 400GbE transceivers.

Some of the first coherent DWDM 400ZRmodules will also use InP modulators, but a majority will be based on SiP, assales of this product will start in 2020. Apart from Acacia, which is becomingpart of Cisco now, Ciena, Huawei, Infinera, Nokia and ZTE also plan tomanufacture 400ZR and ZR+ modules. Most of these companies are likely to useSiP for 400ZR/ZR+ designs.

LightCounting’sIntegratedOptical Devices Report provides an in-depth analysis of the impact made byintegration on the market for optical transceivers and related components in2010-2019. It also presents a forecast for shipments and sales of discrete andintegrated products based on InP, GaAs and SiP technologies for 2020–2025. Theforecast is segmented by main applications, including Ethernet, WDM, ActiveOptical Cables (AOCs) and Embedded Optical Modules (EOMs) and a few others.Products are sorted by data rate, reach, and form factor into more than 150categories. The report also discusses the supply chain for SiP products andprofiles many of the start-up companies developing integrated optical devices.A forecast for the adoption of co-packaged optics in 2023-2028 is alsoincluded.

More information on the report isavailable