In a pioneering achievement, researchers in Japan have developed the world’s first “n-channel” diamond-based transistor, propelling us closer to processors capable of functioning at ultra-high temperatures. This breakthrough not only eliminates the necessity for direct cooling but also expands the operational range of processors to extreme environments.

By integrating diamond into a transistor—a fundamental component responsible for electrical switching between 1s and 0s when voltage is applied—the research heralds the prospect of smaller, faster, and more energy-efficient electronics. Unlike conventional components, diamond-based transistors exhibit resilience in harsh conditions, withstanding temperatures exceeding 572 degrees Fahrenheit (300 degrees Celsius) and enduring higher voltages before reaching breakdown.

Silicon, the conventional material for transistors since the 1960s, has been approaching its physical limits due to the diminishing size of the manufacturing process, nearing the width of silicon atoms. This limitation underscores the urgency for alternative materials like diamond to drive innovation in semiconductor technology.

Transistors come in various types, with the metal-oxide-semiconductor field-effect transistor (MOSFET) being the most prevalent. Within MOSFETs, n-channel and p-channel configurations dictate electron or hole conduction, respectively. N-channel transistors, utilized in high-side power switches, harness electrons for charge transport.

In their groundbreaking study, the researchers constructed a transistor comprising two phosphorus-doped diamond epilayers to serve as the n-channel. Phosphorus doping enhances conductivity, facilitating the flow of free electrons essential for transistor operation. The transistor architecture, featuring annealed titanium contacts and aluminum trioxide insulation, culminated in the world’s first functional n-channel MOSFET transistor fabricated using diamond.

Conductivity tests revealed impressive performance, with the n-type diamond MOSFETs demonstrating high field-effect mobility at temperatures up to 573K, surpassing other wide-bandgap semiconductor-based transistors. Diamond’s wide bandgap, compared to silicon, enables operation at higher voltages and frequencies, making it an ideal candidate for next-generation electronics.

This milestone follows previous breakthroughs in diamond transistor technology, including the creation of p-channel wide-bandgap transistors. With potential applications in energy-efficient electronics, spintronic devices, and sensors for harsh environments, diamond semiconductors hold promise for revolutionizing various industries, from space exploration to electric vehicles and consumer electronics.

By Impact Lab