Microchip smells trouble

The new microchip can be produced in pre-existing microelectronics factories Keystone Archive

A single microchip packing three different sensors is ready to sniff out potential trouble, as it detects and measures dangerous gases.

Zurich’s Federal Institute of Technology developed the chip with other European universities. The device could be used for different applications, such as monitoring air quality in closed rooms.

The researchers say it can detect dangerous, and sometimes poisonous, substances in the air, like benzene from petrol pumps or chemicals from dry-cleaning installations.

Just seven millimetres long, the chip is small enough to be integrated into handheld or credit card-sized units. The scientists behind the project say that because of its size and the variety of potential uses, the system is ready for low-cost mass production.

Its small size has other advantages too. “Power consumption is very low due to its microstructuring,” said Andreas Hierlemann, one of the project leaders.

The chip also carries all the electronics it needs for the job. “Its very easy to hook it up to a control system since the device is very stable, ” Hierlemann told swissinfo.

Nose is more sensitive

Part of the chip’s surface is a detector coated with special polymers, which absorb airborne molecules, mainly organic compounds. The polymers’ properties change when they come into contact with the molecules.

Each compound presents a specific signal, and the chip can identify the compounds as well as their concentration, giving out a warning if a critical limit is reached.

As the polymers react to particular compounds, the researchers suggest that an array of sensor chips would permit detection of a broader variety of dangerous chemicals.

The scientists say this type of detector is still a long way from having the sensitivity of the human nose though, and can only have specific uses.

The monitoring system could also be potentially used to detect cases of chemical terrorism. “You could issue an alarm if something dangerous was in the air,” said Hierlimann.

The researchers have designed this type of detector chip, but two to three years further development is still required before it reaches the market. “There is no major obstacle to developing hand-held devices for the public,” Hierlemann told swissinfo.

The system is part of collaboration among Zurich, the University of Tübingen in Germany and the Italian University of Bologna. The research team’s results are published in this week’s issue of Nature.

swissinfo with agencies