CMOS-integrated high-speed MSM germanium waveguide photodetector.

Area of Science:

• Materials Science
• Electrical Engineering
• Optoelectronics

Background:

• Photodetectors are crucial for optical communication systems.
• Integrating photodetectors with CMOS technology is essential for miniaturization and performance enhancement.
• Germanium-on-insulator (GOI) offers a promising platform for optoelectronic devices compatible with silicon fabrication.

Purpose of the Study:

• To demonstrate a compact waveguide-integrated Germanium-on-insulator (GOI) photodetector.
• To achieve high-speed operation at 40Gbps.
• To enable monolithic integration of germanium into the CMOS fabrication process.

Main Methods:

• Monolithic integration of thin single-crystalline germanium (Ge) into a front-end CMOS stack.
• Utilizing rapid melt growth during source-drain implant activation anneal for Ge crystallization.
• Waveguide integration for efficient light coupling.

Main Results:

• A compact waveguide-integrated GOI photodetector was successfully fabricated.
• The photodetector exhibits a low capacitance of 10 +/- 2fF.
• The device operates reliably at a data rate of 40Gbps.

Conclusions:

• The demonstrated GOI photodetector is suitable for high-speed optical communication.
• The monolithic integration method using rapid melt growth is effective for fabricating advanced optoelectronic devices within CMOS processes.
• This work paves the way for next-generation, high-performance integrated photonic circuits.