Mastering the master: surface relief grating masters for AR, VR, and MR applications

Area of Science:

• Optics and Photonics
• Nanotechnology
• Display Technology

Background:

• Augmented, virtual, and mixed reality (AR/VR/MR) devices require compact optical elements.
• Surface relief gratings (SRGs) are key for diffractive optical waveguides in AR/VR/MR.
• Uniform eye-box illumination is critical for AR/VR/MR display clarity.

Purpose of the Study:

• To demonstrate advanced nanopatterning techniques for surface relief gratings (SRGs).
• To achieve precise control over SRG features for improved optical performance in AR/VR/MR devices.
• To explore fabrication methods for high-performance diffractive optical elements.

Main Methods:

• Utilized advanced electron beam lithography for master stamp fabrication.
• Employed reactive ion beam trimming etching for precise pattern transfer and shaping.
• Investigated control over sidewall angle, pitch, critical dimension, and depth variation.

Main Results:

• Demonstrated high-fidelity nanopatterning of slanted and blazed SRGs.
• Achieved precise control over SRG sidewall angle and shape.
• Showcased modulation capabilities for pitch, critical dimension, and continuous depth variation.

Conclusions:

• Electron beam lithography and reactive ion beam trimming are effective for fabricating high-performance SRGs.
• These techniques offer precise control over nanoscale features essential for AR/VR/MR optical elements.
• The demonstrated methods support the development of advanced diffractive optical waveguides for immersive technologies.