Ultrathin Single Crystal Diamond Membrane

Ultrathin membranes (~100nm) with high surface and geometric qualities at affordable fabrication costs.

Background

Single Crystal Diamond (SCD) membranes have particular properties (i.e. hardness, thermal conductivity, optical, etc.) that make it very attractive for applications ranging from lasers and spectrometers through to chemical, biological and pressure sensors. Many applications require ultrathin membranes made of high-quality SCDs, such as:

  • Sensors (Bio, Chemical, Pressure)
  • Quantum communication and Quantum computers (optical cavities for quantum computing)
  • Windows on X-ray diffraction and other optical devices
  • Micro-ring resonators
  • Particle detectors (UV, X-ray, electron beam)
  • MEMS resonators
  • RAMAN detector windows

Existing commercially available membranes are expensive: 5,000nm - 20,000nm thick membranes cost between US$1,000 - $5,000 and offer comparatively poor surface quality, and structural stability and robustness.

Technology

Researchers from the University of Melbourne have developed a technique to fabricate ultra-thin membranes (100nm) from SCD that offers high surface and geometric qualities suitable for a wide range of applications including optical and sensing. The technique utilises a unique method in addition to microwave plasma CVD process to grow high-quality diamond windows on the ion-implanted substrate, and thinning of the membrane through Reactive Ion Etching (RIE). Product design and initial fabrication results and parameters are shown in Figures 1 and 2.

Figure 1. Design of ultrathin SCD windows

Figure 2. Optical images of (a) 6x6 SCD windows (b) 1x1 SCD window (c) 2x2 SCD windows (d) SEM image after lift-off (e) SEM of thin membrane (~300nm) (f) AFM after RIE with Rrms ~3nm

Intellectual Property

The technology and its method of fabrication are the subject of patent application (PCT/AU2015/000625), and further research and development is underway to explore new applications of the technology.

Inventors

This technique for fabricating ultra-thin SCD membranes was developed by Afaq Piracha, Prof Steven Prawer and colleagues in the School of Physics in the Faculty of Science at the University of Melbourne, Australia.

Licensing Contact

Fabian Lim
Technology Licensing Services
The University of Melbourne
T: +61 3 9035 6020
E: fabian.lim@unimelb.edu.au