Surface micromachined tunable 1.55 μm-VCSEL with 102 nm continuous single-mode tuning

Area of Science:

• Photonics and Laser Technology
• Semiconductor Devices
• Micro-Electro-Mechanical Systems (MEMS)

Background:

• Vertical-cavity surface-emitting lasers (VCSELs) are crucial components in optical communication and sensing.
• Achieving wide, single-mode wavelength tuning in VCSELs remains a significant challenge for advanced applications.
• Existing tuning methods often involve complex fabrication or limited tuning ranges.

Purpose of the Study:

• To demonstrate a VCSEL with unprecedented single-mode wavelength tuning range.
• To utilize micro-electro-mechanical actuation for tunable laser fabrication.
• To enable cost-effective, on-wafer mass production of tunable VCSELs.

Main Methods:

• Fabrication of a tunable VCSEL incorporating a micro-electro-mechanical system (MEMS) actuated mirror membrane.
• Utilizing low-cost dielectric materials (SiOx/SiNy) deposited via low-temperature Plasma Enhanced Chemical Vapor Deposition (PECVD).
• Integration of surface micro-machining techniques for on-wafer manufacturability.

Main Results:

• Demonstration of a VCSEL with a single-mode wavelength tuning range exceeding 102 nm around 1550 nm.
• Achieved fiber-coupled optical output power of up to 3.5 mW, remaining above 2 mW across the tuning range.
• Maintained side-mode suppression ratios greater than 45 dB throughout the tuning operation.

Conclusions:

• The developed MEMS-based tunable VCSEL offers a significant advancement in laser technology.
• The low-temperature PECVD fabrication process using dielectric materials facilitates cost-effective mass production.
• This technology opens new possibilities for tunable laser sources in various optical systems.