M. Gazicki et al., DEPOSITION AND PROPERTIES OF GERMANIUM CARBON FILMS DEPOSITED FROM TETRAMETHYLGERMANIUM IN A PARALLEL-PLATE RF DISCHARGE/, Thin solid films, 322(1-2), 1998, pp. 123-131
Thin germanium/carbon films were prepared by an RF glow discharge deco
mposition of tetramethylgermanium in a stream of argon using typical p
arallel plate reactor. Both the deposition yield and the physical prop
erties of the films strongly depended on the power input used. Soft an
d semitransparent polymer-like materials, characterized by a strong de
pendence of their physical properties on the energetic conditions of d
eposition, were obtained at low power magnitudes. High power loads yie
lded hard, glassy, dark brown to black films of relatively high electr
ical conductivity (up to 4 X 10(-3) S/m) and refractive index (approxi
mately 3.0), low value of optical gap (1.3 eV) and density amounting t
o about 2600 kg/m(3) with the above values for a relatively large rang
e remaining independent of deposition conditions. Hard films exhibited
extremely homogeneous surface (down to several nm) while that of soft
films was characterized by circular inhomogeneities at the level of s
everal dozen nanometres. FTIR spectroscopy revealed an incorporation o
f certain amount of oxygen, particularly in the case of the latter mat
erials. Although there are differences in physical properties such as
density or optical gap, as well as several structural differences betw
een the resulting materials, the process to a large extent reminisces
that of the deposition of Ge/C films from tetraethylgermanium in the s
ame equipment. (C) 1998 Elsevier Science S.A. All rights reserved.