Patent ID: 8858713

Claim:
An apparatus for depositing a thin film of material on a substrate comprising: a vacuum chamber, a sample holder disposed inside said vacuum chamber, said sample holder being configured to support said substrate, a gas injector configured to inject a gaseous precursor into the vacuum chamber, a part of said gaseous precursor being configured to react at the surface of the substrate, at least a first cryogenic panel positioned inside the vacuum chamber, and configured to adsorb a part of said gaseous precursor which has not reacted at the surface of the substrate and to release said adsorbed gaseous precursor, a first trap connected to said vacuum chamber and configured to trap a part of said gaseous precursor released by said first cryogenic panel, said first trap having a fixed pumping capacity S 1 , and a second trap configured to trap an other part of said gaseous precursor released by said first cryogenic panel, during the trapping of the part of said desorbed gaseous precursor by the first trap, said second trap having a variable pumping capacity S 2 , and configured to be regulated in function of the gaseous precursor partial pressure, said first trap and said second trap providing a total pumping capacity S=S 1 +S 2 sufficient to maintain the gaseous precursor partial pressure in the vacuum chamber under a determined pressure P L .