A research team from the University of Chinese Academy of Sciences has revealed the failure mechanism of diamond under extreme electrical fields through in situ experiments and molecular dynamics simulations. The study, published in Cell Reports Physical Science, provides critical insights for the design of next-generation diamond-based high-power electronic devices.
Diamond is known for its exceptional physical properties, including ultra-high breakdown field strength and thermal conductivity, making it a promising material for high-frequency and high-power electronics. However, its failure process under extreme electrical fields has remained poorly understood—until now.
The team, led by Professors YAN Qingbo and CHEN Guangchao, used an in situ transmission electron microscopy (TEM) method to observe the breakdown process in real time. They found that diamond failure begins preferentially along the (111) crystal plane, driven by stress-induced lattice distortion and subsequent amorphization, rather than transforming into graphite.
The researchers also used molecular dynamics (MD) simulations to confirm that the (111) surface is more prone to thermal collapse under high temperatures, aligning perfectly with their experimental observations. This study not only clarifies the crystallographic dependency of diamond’s electrical failure but also suggests that using (100)- or (110)-oriented diamond exposed substrates could significantly enhance device durability.
This study not only deepens the understanding of diamond’s behavior under extreme conditions but also opens new pathways for more durable diamond-based electronic devices.
The team said that the findings are expected to influence the design and material selection of diamond-based devices in fields such as quantum computing, high-power transistors, and ultraviolet lasers.
Editor: GAO Yuan
