A natural resort within the city

Dr. Yordan Georgiev develops new ways for the fabrication of nanoelectronics. Source: HZDR

Yordan Georgiev lived in Dresden for the first time shortly after the reunification. In the Bulgarian’s opinion the city has developed for the better since then.

Rays of sunlight illuminate the trees in a lush green, birds chirp in the background, the forest glade radiates a mellow tranquility – it wouldn’t be surprising if a pack of wild boars passed by the next moment. The city’s hustle and bustle seems far away, although the next main street is just around the corner. Dresdner Heide, the green heart of the Saxon capital, extends over an area bigger than 50 square kilometers – right within the city limits. “When I come here, it always feels like a trip to a resort,” Yordan Georgiev exclaims while sitting on a park bench. “I think, it’s a great place to switch off and recharge. It fills me with positive energy.” But as so often the peace of this quiet area is ruined by some small troublemakers: midgets.

Nevertheless, the HZDR researcher from Bulgaria doesn’t seem to notice the little gadflies, which try to suck our blood. It feels like a reflection of his outlook on life: “We have to concentrate on the positive. If you want to accomplish anything great, you need to base it on something progressive. All projects that are merely directed against something will ultimately fail.” Georgiev has seen such a development in his chosen place of residence. When he first came to Dresden 18 years ago – relatively shortly after the German reunification – the city was a different place. “Compared to back then everything is much shinier now,” the physicist recounts. “You can see that a lot of investment went into the region – especially into the research infrastructure.”

Return to Dresden

Not every city was as lucky after the political changes in the 90s, as Yordan Georgiev experienced himself: “In Bulgaria there was quite soon no money left for fundamental research.” That was the moment he accepted an offer from the Forschungszentrum Rossendorf – HZDR’s predecessor. Thanks to his good experience during his first stay it was an easy decision for the researcher to return last September after living and working in Aachen and Ireland – in particular “since Dresden has become one of the leading centers in Europe for microelectronics.” The physicist and his colleagues try to keep this success story going at the next level: the nanometer range.

“In the last 60 years the size of transistors has been reduced from a few centimeters to a few nanometers,” Yordan Georgiev explains. “Currently, the smallest transistor is just 14 nanometers – that’s way smaller than, for example, an AIDS virus.” However, soon this quest for miniaturization will reach a bottleneck. “Probably after the year 2020 it will be almost impossible to go smaller, because of physical complexities,” Georgiev estimates. Thus, innovative ways for the fabrication of the transistors are needed. “There are two approaches: Bottom-up and top-down. So far the last method was mainly used. You start with the bulk material and cut away until you have what you want. However, this is getting more and more complicated due to the tiny structures.”

Therefore, the alternative method tries to turn it upside-down by assembling complex structures from molecules and atoms via self-organization processes. “There seems to be a competition between the two approaches, which one works better,” Georgiev summarizes. Yet, to the Bulgarian scientist it’s clear that such a line of thought leads nowhere. “The future of nanofabrication belongs to smart and inventive combinations of both methods. As in so many other parts of our lives viewing the world in black and white won’t work.”