Method of preparation of a coating comprising at least one oxide layer of metal deuterated or nitride of metal insulator deuterated, on a substrate comprising a silicon

摘要

A layer of at least one metal or a deuterated compound of at least one metal is deposited on a substrate by chemical atomic layer deposition (ALD) using at least a non-deuterated precursor of the metal or metal compound and a deuterated reagent, which, for a silicon substrate, avoids the growth of parasitic SiO2 under a layer of, e.g., a high-K dielectric metal oxide. Preferred Features: The substrate is selected from pure Si, SiGe, SiC, polycrystalline silicon and substrates having an ALD-deposited monolayer of a compound selected from MoSi2, MoGe2, MoSixNy, and MoGexNy, starting from deuterated reactants such as SiD4, GeD4 and ND3. The metal is selected from Hf, Zr, Ti, Nb, Mo, W, Ta, Al, Mg, Si and Ge. The metal compound is selected from oxides, nitrides, germanides, silicides and ternary compounds of the metal with Si, or Ge and N. The deuterated reactant is selected from heavy water (D2O), D2O2, ND3, SiD4 and GeD4. Deposition is carried out at 500 degrees C or lower, preferably 200-400 degrees C, and the coating can comprise a single layer or many layers. The deuterated compound of at least one metal is a deuterated oxide of a metal having higher electropositivity than Si, such as Al or Mg. Preferably, the deuterated oxide is a mixed oxide of Al or Mg and another metal having lower electropositivity than Mg, such as Hf, or it can be a high permittivity (High-K) oxide, and it is impermeable to hydrogen. The metal oxide can be selected from oxides of Al, Ti, Zr and Hf and oxides having greater permittivity than that of SiO2. A layer of metal selected from Mo, Ti, Ta and Nb can be deposited on the deuterated metal oxide layer by ALD using a chlorinated or brominated metal precursor and the deuterated reagent.