Diamond Wafers for Electronics: A Thin and Adhesive Solution

A new method of using adhesive tape to create ultrathin diamond wafers could aid in the production of diamond-based electronics, which may one day provide a useful alternative to silicon-based designs.

Diamond is an excellent insulator, and at the same time has unusual electronic properties that allow electrons with a certain energy to move with little resistance. This means it can handle high energy with higher efficiency than traditional silicon chip designs.

However, manufacturing practical diamond chips requires large, very thin wafers, similar to the thin silicon wafers used to make modern computer chips, which have proven difficult to create.

now, Chu Zhiqing and colleagues at the University of Hong Kong have discovered a way to use adhesive tape to fabricate extremely thin and flexible diamond wafers.

Chu and his colleagues first embedded nano-sized diamonds in a small silicon wafer and then sprayed methane gas at high temperatures onto them to form a continuous, thin sheet of diamond. Next, we made a small crack on one side of the pasted diamond sheet, and then used regular adhesive tape to peel off the diamond layer.

They say that this exfoliated diamond sheet is extremely thin, less than a micrometer, much thinner than a human hair, and smooth enough to use the kind of etching techniques used to make silicon chips. I discovered.

“This is very reminiscent of the early days of graphene, when cellophane tape was used to produce the first monolayers of graphene from graphite. I never imagined this concept would be applied to diamond. “I did,” he says. julie macpherson At the University of Warwick, UK.

“This new edge-exposed delamination method will enable numerous device designs and experimental approaches,” he says. Mete Atature at Cambridge University. One area that could be particularly useful is increasing control over quantum devices that use diamonds as sensors, he says.

Chu and his colleagues say the diamond films they can produce are about 5 centimeters in diameter, showing that the method works as a proof of principle. andrea ferrari But that’s smaller than the 20 to 30 centimeters that are standard in many wafer processes, and it’s not clear whether the new method can be scaled up, he says.

The manufactured wafers also appear to be polycrystalline, but they are not as smooth and regular as single-crystal diamond, which may limit their use in some applications, McPherson said.