DNa, the buildiNG block for our genes, may provide the key to the bottom-up assem- bly of complex, nanometer- scale circuits, following research performed by scientists based
at Harvard University and the Massachusetts Institute of Technology (MIT)
that used the biomolecule to carve patterns in graphene lying on the surface
of a silicon wafer.
However, researchers need to overcome significant obstacles to make the
processes viable on an industrial scale.
Today, integrated circuit (IC) manufacturers use exclusively top-down
techniques to define the transistors
and wiring that make up ICs based
on optical lithography. Light shone
through a reticle defines features on
a chemical resist spun onto the surface of a silicon wafer. The resist typically hardens where the light strikes
but remains soft enough to wash off
elsewhere, so that materials can be deposited or implanted in the areas not
masked by the resist.
Almost 20 years ago, the semicon-
ductor industry moved to use light in
in images a through c, metallized Dna (in red) is built up to form the letter o on a graphene
substrate. in image d, treatment with oxygen plasma has etched the letter into the graphene.
Life Points the Way
to a new template
While significant obstacles remain, researchers are optimistic about
using DNA to guide graphene into complex circuit shapes on silicon.
Science | DOI: 10.1145/2534706.2534711 Chris Edwards