The demand for more powerful, potent, and denser computer chips is constantly growing with the rise of electronic gadgets and data centers. Traditional methods for making these chips involve bulky 3D materials, which make stacking difficult. However, a team of interdisciplinary MIT researchers has developed a new technique that can grow transistors from ultrathin 2D materials directly on top of fully fabricated silicon chips.
The researchers published their findings in the peer-reviewed scientific journal Nature Nanotechnology. The new process involves growing smooth and uniform layers of 2D materials across 8-inch wafers, which can be critical for commercial applications where larger wafer sizes are typical.
The team focused on using molybdenum disulfide, a flexible and transparent 2D material with powerful electronic and photonic properties. Typically, these thin films are grown using metal-organic chemical vapor deposition (MOCVD) at temperatures above 1022 degrees Fahrenheit, which can degrade silicon circuits.
To overcome this, the researchers designed and built a new furnace with two chambers: the front, where the silicon wafer is placed in a low-temperature region, and the back, a high-temperature region. Vaporized molybdenum and sulfur compounds are then pumped into the furnace. Molybdenum stays and decomposes at the front, while the sulfur compound flows into the hotter rear and decomposes before flowing back into the front to react and grow molybdenum disulfide on the surface of the wafer.
This innovative technique is a significant advancement in the development of more powerful and denser computer chips. With this breakthrough, the researchers were able to construct multistory building-like structures, significantly increasing the density of integrated circuits. In the future, the team hopes to fine-tune their technique and explore growing 2D materials on everyday surfaces like textiles and paper, potentially revolutionizing the industry.
