New method enables mass production of flexible diamond membranes

A research team has developed a method for massively producing ultrathin and ultra-flexible diamond membranes.

The results are published in Nature. The researchers were led by Professor Zhiqin Chu, Associate Professor in the Department of Electrical & Electronic Engineering, and Professor Yuan Lin, Professor in the Department of Mechanical Engineering, Faculty of Engineering at the University of Hong Kong (HKU).

These ultrathin and ultra-flexible diamond membranes are compatible with existing semiconductor manufacturing technologies, and thus can, in principle, be fabricated into a variety of electronic, photonic, mechanical, acoustic, and quantum devices.

The innovative edge-exposed exfoliation method discovered by the team facilitates the rapid production of scalable, free-standing diamond membranes. This approach is superior to traditional methods, which are typically time-consuming, costly and limited in size. Remarkably, the new process can manufacture a two-inch wafer within 10 seconds, offering unmatched efficiency and scalability.

These ultra-flat diamond surfaces, essential for high-precision micromanufacturing, along with the flexibility of the membranes, open up new possibilities for next-generation flexible and wearable electronic and photonic devices. The research team envisions significant industrial applications in electronics, photonics, mechanics, thermics, acoustics, and quantum technologies.

“We hope to promote the usage of the high-figure-of-merit diamond membrane into various fields, and to commercialize this cutting-edge technology and deliver premium diamond membranes, setting a new standard in the semiconductor industry. We are eager to collaborate with academic and industry partners to bring this revolutionary product to market and accelerate the arrival of the diamond era,” said Professor Chu.

Diamonds, renowned globally as valuable gemstones, possess exceptional versatility in various scientific and engineering applications. They are the hardest natural material, boasting unparalleled thermal conductivity at room temperature, extremely high carrier mobility, dielectric breakdown strength, an ultrawide bandgap, and optical transparency spanning from the infrared to the deep-ultraviolet spectrum.

These remarkable properties make diamonds ideal for fabricating advanced high-power, high-frequency electronic devices, photonic devices, and heat spreaders to cool high-power density electronic components, such as those in processors, semiconductor lasers, and electric vehicles.

However, the inert nature and rigid crystal structure of diamonds pose significant challenges in fabrication and mass production, particularly for ultrathin and freestanding diamond membranes, thereby restricting their widespread usage.