Transceivers, Heat Dissipation, and Wearables: Are Diamonds the Future of Microelectronics?

The unique properties and structure of diamonds make it an incredibly useful material in electronic applications, ranging from wearable devices to radio transceivers. Diamonds could allow electronic devices to become more durable, last longer, and perform better.

Diamonds are proving continually pivotal in the creation of innovative electronics. From qubit creation to semiconductor manufacturing to possibly even being the key to long-lived batteries, diamonds are changing the way devices are designed.
Diamonds could allow electronic devices to become more durable, last longer, and perform better.

The Tiniest Transceiver

Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences created the world's smallest radio transceiver by artificially creating tiny defects in atomic-sized pink diamonds. This was accomplished by replacing a carbon atom with a nitrogen atom and removing a neighboring atom to create a hole—this is referred to as a nitrogen-vacancy (NV) center.
The defect is sensitive to weak electromagnetic fields and can emit single photons, resulting in the ability to convert information into light. During experiments, researchers used a green laser to provide the defective diamond with energy and then produced radio waves which the NV center responded to by emitting red light. The red light could then be converted into an electric current, which in turn could be converted to sound.
The resulting tiny transceiver is capable of operating at high temperatures and has a wide array of applications from use in space exploration to biomedical devices.

Performance results for the diamond radio transceiver. Image courtesy of Harvard University Laboratory for Nanoscale Optics (PDF).

Creating Artificial Diamonds for Wearable Devices

AKHAN Semiconductor, a company based in Illinois, is currently creating artificial diamond with methane gas to produce flexible, transparent displays. It is expected the displays could be used in a variety of applications: aerospace, automotive, mobile devices, and wearables. AKHAN also wants to replace the silicon in chips with diamonds.

Adam Khan, founder of AKHAN Semiconductor. Image courtesy of AKHAN Semiconductor.

Diamonds produced artificially are different from synthetic diamonds in that they are formed around a diamond “seed” using a reactor that heats plasma up to 8,000 degrees Fahrenheit, which results in the atoms layering atom-by-atom. The plasma is composed of an argon, hydrogen, and methane mixture that is then heated by microwaves.
This technology will enable the company to create thin, ultra strong display components that are resistant to shattering and scratching. The properties of diamonds also result in better heat distribution and dissipation.
Founder of AKHAN Semiconductor, Adam Khan, patented the technology to artificially produce diamonds for electronics in 2012 and is the first company to focus on diamond-based electronics.

Diamonds for Heat Dissipation

Researchers from the A*STAR Institute of Microelectronics have been experimenting with using a layer of diamond in gallium nitride transistor chips to enhance heat dissipation. The researchers' results were confirmed through simulations, as well as experimentation.

A test chip with a diamond heat dissipation layer. Image courtesy of A*STAR Institute of Microelectronics.

In experiments, a thin layer of diamond was added to a chip that was created using chemical vapor deposition. The test chip had eight hotspots that were 0.45x0.3 mm in size. After the chip and the diamond layer were bonded, the combined device was connected to a micro-cooler which contains a microchannel which uses water to remove heat.
In tests, the diamond layer resulted in the maximum temperature that was 27% lower than the max temperature of copper based heat dissipation layers and 40% lower than chops with no heat dissipation layer when tested with up to 120 watts of power.
In the team’s simulations, the results were similar in that the diamond layer resulted in better heat dissipation and that using a thicker layer of diamond could lead to even better heat dissipation.


Featured image used courtesy of the Harvard John A. Paulson School of Engineering and Applied Sciences.