The HZB physicist Dr. Christoph Merschjann then investigated the transport properties in samples of TGCN with time-resolved absorption measurements in the femto- to nanosecond range in the JULiq laser laboratory, a joint lab between HZB and Freie Universität Berlin. Such laser experiments make it possible to combine macroscopic conductivity with microscopic transport models. From the measured data he was able to deduce how the charge carriers diffuse through the material: "They do not leave the hexagonal honeycombs of triazine units horizontally, but move obliquely to the next triazine unit in the neighboring plane. They move along tubular channels through the crystal structure." This mechanism could explain that the conductivity perpendicular to the planes is significantly higher than in the planes. However, it is probably not sufficient to explain the actual measured factor of 65. "We have not yet fully understood the transport properties in this material and want to investigate them further," announces Merschjann.
"TGCN is therefore so far the best candidate to replace common inorganic semiconductors such as silicon with their partially critical "dotants" of rare elements," says Bojdys. The developed manufacturing process leads to flat layers of semiconducting TGCN on insulating quartz glass. According to the scientists, this should enable upscaling and simple device production.
More information: https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.201902314