But the hardware is archaic and uses toxic and expensive manufacturing processes. Silicon chip fabrication plants, with their “clean rooms,” are a perfect example: They clean the chips with organic solvents or with inorganic reagents like sulfuric acid, which are dangerous and don’t break down. This approach is starting to change, however, and we’re going to see dramatic changes in chip technology. Chips are made of silicates — they’re glass, basically. Scientists at Princeton and the University of California at Santa Barbara are looking for better ways to make chips by studying diatoms, algae with cell walls made of silica, which grows through crystallization — the same way silicates are grown for chips. The important difference is that the chemical process takes place in water. There’s no need for toxic solvents or reagents. The diatom self-assembles its silicon shell using materials common in seawater. Industries that want to clean up their manufacturing should be investigating how they might transition to this new way of making silicon chips.
But that’s not all. Researchers are looking at nature for ways to solve the overheating problem in electronics. There are people looking at how to mimic the heat-dissipating structures of the butterfly wing and apply that to the computer chip structure itself. There’s a company in San Rafael, Calif., called Pax Scientific that is studying the way nature directs flow using Fibonacci sequences — the logarithmic spirals that are found throughout nature, in structures ranging from nautilus shells to tornadoes — to design better computer fans. They’re being tested now; they yield about 35 to 50 percent energy savings and are 75 percent quieter.
S+B: It sounds as if much of the progress in technology comes out of materials science.
BENYUS: The two fields that have the longest legacy of bio-inspiration are computing and materials. The traditional processes for turning materials into finished products are incredibly wasteful and polluting. They’re called “heat, beat, and treat”: You start with a bulk material, carve it down, heat it up, beat it with enormous pressure, and treat it with chemicals. What you get is 96 percent waste, 4 percent product.
Researchers are now looking at the processes that nature uses to make its materials — from ceramics like shell, bone, and teeth to the soft and yet amazingly durable materials like spider silk — to identify common principles. There are several primary differences. First, life does its manufacturing in or near its own body, so its methods have to be life-friendly. A spider spins its silk “on board.” It can’t take a chance with “heat, beat, and treat.” It uses little energy; there’s no waste and no hazardous byproduct. Second, nature conducts its chemistry in water. We conduct industrial chemistry in solvents like sulfuric acid. Third, our manufacturing processes use all the elements in the periodic table — even the toxic ones — and we use crude, brute-force recipes. But life uses a subset of the elements, just a few, and it uses very elegant, low-energy recipes.
One of the problems with “heat, beat, and treat” is that it tends to produce brittle materials that crack or break easily. The abalone shell, by contrast, is a model of flexibility and resilience. The mother-of-pearl inside is a layered structure of mineral plates and protein sheets that self-assembles out of seawater; the mineral layers are composed of hexagonal plates stacked and offset like bricks in a garden wall. In between the mineral layers are soft protein layers — a sort of “mortar” that holds the bricks together. The protein layer is what makes it so tough. When the mother-of-pearl is compressed, the layers of mineral slide on the protein rather than fracturing. When a crack starts, the soft intervening layers dissipate the energy of the fissure. The abalone shell is twice as durable as the ceramics we use in jet engines. The natural product works better. It’s tougher. It’s manufactured silently, in water. It doesn’t use massive amounts of energy to keep kilns fired up; in fact, if you fired it, you’d destroy the soft part that gives it durability.