Now that Intel will definitely be introducing its 22-nm Tri-Gate transistor—referred to as a 3-D chip due its 3-D ridge (or fin, thus the alternative name, FinFET) in which electrons runs through—it seems the era of 3-D chips are here sooner than expected. (Read and watch this interesting interview with Intel Senior Fellow Mark Bohr on how we got to this point.)
With this as its context, Dutch researchers from MESA+ Institute at the University of Twente, University of Eindhoven, ASML company and TNO Institute have developed processes by which they can rapidly fabricate “large 3-D photonic in mono-crystalline silicon using CMOS compatible processes” that should enable novel fabrication methods for computer chips.
The researchers have published their work in a series of three papers and in the one published by the Journal of Vacuum Science and Technology have been able to fabricate a 3-D nanostructure in silicon by making etch marks on two sides of s wafer.
"There are many advantages of our fabrication route" says Willem Tjerkstra, a researcher at the MESA+ Institute in an interview with Nanowerk. "A complex 3-D structure can be made in only two etching steps, instead of tediously making such a structure by stacking layer-by-layer, as in standard CMOS-compatible fabrication. In our paper, we propose that our method allows the realization of 3-D computer chips that have more functional units concentrated on the same area. We also predict the realization of chips on different sides of liquid channels for microfluidic, or for cooling purposes."
In the two succeeding papers, the researchers described a “3D etch-masking method to realize a complex 3-D periodic array (a crystal structure) of pores in silicon” and then in the third paper observed for the first time the long-predicted phenomenon of the spontaneous emission of light from quantum dots in a 3-D photonic band gap.
It will be interesting to see if techniques such as these find their way into the next generation of 3-D chips when dimensions go down to 14nm and then 10nm.