Next-generation nanoelectronics requires development of new thermally and mechanically stable materials with relative permittivity (k) as close to 1 as possible. In June 2020, Hong et al. presented ICP-CVD-deposited amorphous boron nitride (a-BN) with very low k of 1.78 . This a-BN also turned out to be thermally, chemically, and mechanically stable, and having high breakdown voltage, thus fulfilling all requirements for practical applications. A three-nanometer thick layer of this material was obtained by low-temperature remote inductively coupled plasma–chemical vapor deposition (ICP-CVD) with borazinå as the precursor.
Two years later Lin et al. conducted seemingly identical synthesis, but obtained a compound with noticeably different properties . When synthesis conditions were identical (based on the information in the article) to those of the Hong experiment, the boron to nitrogen ratio (B:N) was ~2.64, whereas the B:N in the original article films was 1.0. To obtain the same B:N, Lin’s team had to explicitly add nitrogen molecules to the gas flow.
In order to understand why supposedly equivalent conditions lead to different products, it is necessary to understand the process at the atomic level, which is not possible with current experimental techniques. As Richard Feynman famously quoted: "What I cannot create, I do not understand." Following this principle, we have constructed a digital twin of this system to comprehensively reconstruct the ICP-CVD process, encompassing all its intricate details and established the most likely reason for the discrepancy between Hong’s and Lin’s experiments.