The deposition of boron carbonitride layers
on silicon substrates by a microwave plasma enhanced
chemical vapour deposition (MW-PECVD) process using
N-trimethylborazine (TMB) and benzene as precursors
is presented. As plasma gases argon and nitrogen
were used. In this investigation we focus on the influence
of the gas composition, substrate temperature and
-bias on the layer composition, layer structure as well as
the thermal stability. The films were analyzed with respect
to their composition and bonding structure using
elastic recoil detection analysis (ERDA) and X-ray
photoelectron spectroscopy (XPS). Furthermore, nanoindentation
measurements before and after annealing
tests at 500 and 700°C were performed. The measurements
show a strong dependence of the structure and
mechanical properties on the substrate temperature.
The hydrogen content strongly decreases to 8 at.% with
higher substrate temperatures. Simultaneously, the layer
hardness and Youngs modulus increase up to 21 and
173 GPa, respectively. The hardness does not decrease
after annealing for 1 hour at 700°C.