London: Scientists are developing a chip with three or more processors stacked vertically to ensure an unprecedented speed, memory and calculating power, better functionality and wireless connectivity, reveals a study.

"It's the logical step in electronics development, because it allows a large increase in terms of efficiency," said Yusuf Leblebici, director of Microelectronics Systems Lab, Switzerland, who led the study. 

Unitl now, chips could only be assembled horizontally via connections along their edges. They were connected vertically by several hundred very thin copper microtubes. These wires passed through tiny openings, called Through-Silicon-Vias (TSV), made in the core of the silicon layer of each chip.

"This superposition reduces the distance between circuits, and thus considerably improves the speed of data exchange," explained Microelectronics researcher Yuksel Temiz, according to a university statement. 

The team had to overcome a number of difficulties, such as the fragility of the copper connections as they are miniaturised to an extreme degree (about 50 micrometers in thickness), and are as thin as human hair. 

"In three years of work, we tested thousands of TSV connections, and had more than 900 functioning simultaneously," said Leblebici. 

"Now we have a production process that is really efficient, the laboratory has also manufactured 3D multi-core processors, connected by a TSV network," he added. 

The technology will initially be made available to a number of academic research teams for further development before being commercialised.