Scientists from NASA's Ames Research Center, Moffett Field,
CA, have invented a biological method to make structures
that could be used to produce electronics 10 to 100 times
smaller than today's components.
As part of their new method, the scientists genetically engineered
proteins from "extremophile" microbes to grow onto
semiconductor materials.
The microbes' environments are "extreme" to us
-- near-boiling, acidic hot springs -- but just right for
the biological organisms to grow mesh-like structures, known
as "chaperonins," presumably for their accompanying
role.
"We took a gene from a single-celled organism,
Sulfolobus shibatae, which lives in near-boiling acid mud,
and changed the gene to add instructions that describe how
to make a protein that sticks to gold or semiconductors,"
said Andrew McMillan, a leader of the project.
"What is novel in our work," he continued, "is
that we designed this protein so that when it self-assembles
into a two-dimensional lattice or template, it also is able
to capture metal and semiconductor particles at specific
locations on the template surface."
The genetically engineered proteins form lattice-like structures
that act as templates, and particles of gold or semiconductor
material (cadmium selenide/zinc sulfide) stick to them.
According to McMillan, the minute pieces that adhere to
the protein lattice are "quantum dots" that are
about one to 10 nanometers across. Today's standard computer
chips have features that are roughly 130 nanometers apart.
