A technique is developed for preparing ultrafine-particle GeO2 . H2O u
ndergoing peptization in alkaline and acidic solutions to form stable
sols, which can be transformed into continuous uniform GeO2 films. Nan
ocrystalline diamond-structure germanium with a particle size from 10-
15 to 70-80 nm is prepared from these films by hydrogen reduction at t
emperatures above 420 degrees C. The obtained results demonstrate that
sol-gel processing can be used to produce Ge films of controlled part
icle size.