Researchers have developed a new technique to produce thin films of
germanium(锗) crystals -- key
components1 for next-generation electronic devices such as advanced large-scale integrated circuits and flexible electronics, which are required for
gadgets2 that move or bend. Unlike conventional methods, the new approach does not require high temperatures or other crystals to act as seeds to grow the germanium crystal. And, the researchers say, the new method can be used to produce germanium films with a very large area, allowing for more potential applications.
"This is the
realization3 of the dreams of crystal-growth researchers," says Taizoh Sadoh of Kyushu University. "This unique method will open new ways to create advanced flexible electronics."
Sadoh is an author of the paper describing the new work, which appears in the AIP Publishing journal
Applied4 Physics Letters.
Charged particles move through germanium more readily than they do through
silicon5, making germanium a good material for electronics. In particular, it is a
promising6 material for the thin-film
transistors7 that are needed for flexible electronics. However, for use in flexible electronics, the germanium would have to be grown on
malleable8(可塑的) materials, which tend to
soften9 at temperatures above 300°
Celsius10. The challenge, said Sadoh, is to grow germanium at lower temperatures.
Using gold as a
catalyst11, Sadoh and his colleagues were able to grow germanium crystals at a temperature of about 250° Celsius. They were also able to grow them in such a way that their crystal structure has the proper
orientation12 and electrical properties necessary for
technological13 applications.