Direct-bonded diamond membranes for heterogeneous quantum and electronic technologies

Area of Science:

• Materials Science
• Quantum Technology
• Nanotechnology

Background:

• Single-crystal diamond offers exceptional properties for quantum and electronic applications.
• Heteroepitaxial growth limitations hinder the integration and advancement of diamond-based technologies.

Purpose of the Study:

• To develop a versatile and scalable method for integrating single-crystal diamond membranes with diverse substrates.
• To enable the creation of novel heterogeneous diamond-based hybrid systems for advanced applications.

Main Methods:

• Direct bonding of single-crystal diamond membranes to silicon, fused silica, sapphire, thermal oxide, and lithium niobate.
• Customized membrane synthesis, transfer, and dry surface functionalization for minimal contamination.
• Fabrication of ultra-thin diamond membranes with controlled thickness and interfacial properties.

Main Results:

• Achieved bonded crystalline membranes with thicknesses down to 10 nm and sub-nm interfacial regions.
• Measured spin coherence times (T2) of up to 623 ± 21 μs for nitrogen vacancy centers in 150 nm-thick membranes.
• Demonstrated integration of nanophotonic cavities and compatibility with Total Internal Reflection Fluorescence (TIRF) microscopy for cellular interfacing.

Conclusions:

• The developed bonding process provides a scalable toolkit for synthesizing heterogeneous diamond-based hybrid systems.
• This platform facilitates the advancement of diamond-based quantum computing, sensing, and photonic technologies.
• Enables interfacing diamond quantum sensors with biological systems for advanced research.