other tech: top single crystal of semiconductor can be moved to other surfaces

A team led by electrical and computer engineer Zhenqiang (Jack) Ma and materials scientist Max Lagally have developed a process to remove a single-crystal film of semiconductor from the substrate on which it is built. This thin layer (only a couple of hundred nanometers thick) can be transferred to glass, plastic or other flexible materials, opening a wide range of possibilities for flexible electronics.

In addition, the semiconductor film can be flipped as it is transferred to its new substrate, making its other side available for more components. This doubles the possible number of devices that can be placed on the film.

By repeating the process, layers of double-sided, thin-film semiconductors can be stacked together, creating powerful, low-power, three-dimensional electronic devices.

These are single-crystal films of strained silicon or silicon germanium. Strain is introduced in the way they form the membrane. Introducing strain changes the arrangement of atoms in the crystal such that they can achieve much faster device speed while consuming less power.

By including the germanium without destroying the quality of the material, we can achieve devices with two to three orders of magnitude more sensitivity.”

That increased sensitivity could be applied to create superior low-light cameras, or smaller cameras with greater resolution.

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