where pi is the inhibitor vapor pressure and K is the equilibrium constant for adsorption. Two of the models described by Yanguas-Gil et al. are suitable to describe our system: surface site blocking from a "spectator species" in case of hydrogen adsorption "inhibition by reaction byproducts" in case of adsorption by other species. In both cases, their derivation led them to a growth rate proportional to 1 1 + 𝐾𝑝 𝑖 , the main differences being in the dependence of 𝐾 on adsorption, desorption and reaction rates. In our case, because of the dependence of the growth rate to the logarithmic of the hydrogen pressure, the adsorption does not seem to follow a first order Langmuirian behavior. The Langmuir assumes that adsorption occurs on a homogeneous surface, i.e. a perfectly flat surface, whose all adsorption site are equivalent. Our previous study on CVD of B-C films from TMB shows X-ray amorphous films at these deposition temperatures. This, added to the fact that our films present a non-negligible roughness leads to the conclusion that our is quite heterogeneous. This would lead to different adsorption and diffusion paths for the species depending on whether the adsorption site is a carbon or a boron atom and whether diffusion paths involve carbon or boron atoms, particularly for hydrogen. With these considerations, a Temkin isotherm seems more suitable to describe our adsorption system. It can be expressed as: