This flexible semiconductor has the double-helix structure of DNA

In the past, scientists used DNA in nanodevices to manipulate it into mimicking a semiconductor. But what if they could create an inorganic semiconductor that had the properties, such as flexibility, of DNA? 

The world of electronics is about to find out, thanks to researchers at the Technical University of Munich (TUM). The team has discovered a double-helix structure similar to DNA’s in an inorganic semiconductor material which consists of tin (Sn), iodine (I), and phosphorus (P), resulting in its chemical name, SnIP. These elements form in the SnIP around a double-helix configuration.

According to the researchers, the arrangement of atoms into a double-helix structure in the centimeter-long fibers enabled the material to be split into smaller strands. In the lab, the team made fibers as small as five double-helix strands that were just a few nanometers thick. The researchers believe that being able to get the fibers down to such a size allows for a host of nanoelectronic applications.

Being a semiconductor, SnIP must have an inherent band gap, although unlike other inorganic semiconductors, it’s extremely flexible.

“The combination of interesting semiconductor properties and mechanical flexibility gives us great optimism regarding possible applications,” said Tom Nilges, a professor at TUM, whose lab conducted the research, in a press release. “Compared to organic solar cells, we hope to achieve significantly higher stability from the inorganic materials. For example, SnIP remains stable up to around 500°C (930 °F).”

One major breakthrough of the technology is the ability to scale up the production of a double-helix materials beyond the milligram scale. According to Nilges, this is the first double-helix material to be prepared on a gram scale in a simple solid phase reaction via the gas phase.

“The preparation of SnIP is easy and non-toxic components are involved,” said Nilges. “All elements in SnIP are abundant and better available than Gallium (Ga), Indium (In) or Arsenide (As).” Indium phosphide (InP) and gallium arsenide (GaAS) are prominent semiconductors used in modern computer chips containing such toxic or expensive elements.

Possible applications of SnIP include flexible semiconductor devices, solar cells, thermoelectric devices, and water splitting.

Source: Technical University of Munich