Domestically produced chips in optical modules

Domestically produced optical chips are increasingly capable, supporting high-speed data transmission while enhancing supply chain independence and technological sovereignty.

Overview and Motivation

Domestic optical chips are designed for use in optical modules, which are critical for high-speed data transmission in data centers, telecom networks, and high-performance computing (HPC) systems . The push for domestic production is driven by the need to reduce reliance on foreign suppliers, control costs, and foster local innovation in optical communication technologies . Countries like China have focused on developing modules supporting 400G, 800G, and even 1.6T transmission rates, covering form factors such as SFP, QSFP, QSFP-DD, OSFP, and CFP .

Types of Optical Chips

Optical chips are primarily categorized into laser chips and detector chips . Laser chips, including VCSELs (Vertical-Cavity Surface-Emitting Lasers) and DFB (Distributed Feedback) lasers, generate light for data transmission, offering high data rates, low power consumption, and reliability . Detector chips convert incoming optical signals back into electrical signals, enabling data processing in optical receivers . These chips are integrated with driver ICs, TIAs, and DSP ICs to form complete optical modules .

Production Process

The fabrication of domestic optical chips involves several precise steps :

• Wafer Growth: High-purity epitaxial crystals are grown using MOVPE reactors to form multilayered semiconductor structures.
• Chipping and Assembly: Wafers are cut into bars, cleaved, coated, and separated into individual chips. Automatic die and wire bonders ensure high positional accuracy.
• Testing and Aging: Chips undergo rigorous testing and aging to ensure reliability and performance before integration into modules.

Advantages of Domestic Chips

Domestic optical modules offer several benefits:

• High-speed performance: Support for 100G, 400G, 800G, and beyond .
• Power efficiency: Optimized thermal management reduces energy consumption .
• Monitoring and diagnostics: Integration of DDM/DOM ICs provides real-time feedback on temperature, voltage, current, and optical power .
• Cost-effectiveness: Domestic production lowers procurement costs and enables large-scale deployment .
• Supply chain resilience: Local production reduces dependency on imported components .

Challenges

Despite progress, domestic optical chips face challenges:

• High-speed performance: Achieving multi-channel 400G/800G and 1.6T transmission with low error rates requires advanced design and manufacturing .
• Process technology: Advanced fabrication techniques like silicon photonics (SiPh), EML, and TFLN demand precise wafer-level processes .
• Supply chain maturity: Some materials and specialized IC components still rely on imports .
• Standards compliance: Modules must meet IEEE, ITU-T, and OIF standards for interoperability .

Future Trends

The domestic optical chip industry is moving toward:

• Higher data rates: Development of 1.6T and 3.2T modules with advanced modulation schemes like PAM4 and QAM .
• Co-packaged optics (CPO): Placing optical chips closer to switch ASICs to reduce latency and power consumption .
• Scenario expansion: Applications in automotive optical modules, satellite internet, and other emerging fields .
• Technological independence: Localization of high-end optical chips and DSP ICs to achieve full control over the supply chain . In summary, domestically produced optical chips are rapidly advancing, offering competitive performance and strategic advantages while continuing to overcome technical and supply chain challenges. Their development is crucial for high-speed optical communication and the broader goal of technological self-reliance.