Flexible mirror micromachined in silicon.

Area of Science:

• Microelectromechanical Systems (MEMS)
• Optics
• Materials Science

Background:

• Flexible mirrors are crucial for adaptive optics and beam steering.
• Existing technologies often face limitations in integration, control, and optical quality.

Purpose of the Study:

• To fabricate and characterize an electrostatically controlled flexible mirror on a silicon chip.
• To assess the optical quality and electrostatic controllability of the fabricated mirror.

Main Methods:

• Bulk micromachining of a silicon chip.
• Fabrication of a 10.5 mm × 10.5 mm silicon-nitride diaphragm mirror with an aluminum reflective coating.
• Electrostatic control using an integrated actuator array.

Main Results:

• The mirror exhibits an initial planar reflecting surface with a mean-square deviation of ~λ/8 (λ = 633 nm).
• The mirror's surface shape can be electrostatically controlled via the integrated actuators.
• The device demonstrates good initial optical quality.

Conclusions:

• The developed on-chip flexible mirror integrates electrostatic control with good optical performance.
• This technology is suitable for various electro-optical applications requiring precise beam manipulation.
• The fabrication method offers a pathway for scalable production of adaptive optical components.