Rohm and Haas Electronic Materials of North Andover, Massachusetts USA and the
Laboratory for Photonics and Nanonstructrues (LPN) at CNRS, Marcoussis, France
have devised an new process to grow germanium films on germanium at low temperatures
in a MOCVD reactor, according to a report from III-Vs
Review. The work is reportedly targeting Ge/III-V hetero devices, and
the researchers hope to advance the integration of compoundsemi devices on silicon
and other substrates. The breakthrough was presented at the ACCGE-16 at the Big Sky Resort in Montana in the USA. Using the new and less toxic precursor isobutylgermane, the group at
LPN-CNRS demonstrated the growth of high quality germanium films at temperatures
as low 500C. The low growth temperature and the new precursor are expected to
virtually eliminate a memory effect of germanium in the III-V material.
Many researchers have hoped that Germanium which has about three times the
electron mobility of silicon, could lead to faster transistor switching times.
Electrical engineers have also developed a process for combining high-K oxides
with both silicon and germanium. This could be important for integrating compoundsemi
and silicon devices. However, Germanium’s small bandgap results in greater electrical
leakage than silicon. Stanford’s Center for Integrated Systems has been studying
the feasibility of using germanium, and it has received aid from the Defense
Advanced Research Projects Agency (DARPA).