Si precursors for deposition of SiN at low temperatures
First Claim
1. A plasma enhanced atomic layer deposition method of depositing a silicon nitride thin film on a substrate in a reaction space, the method comprising a plurality of deposition cycles, each deposition cycle comprising:
- (a) introducing a vapor-phase silicon reactant comprising iodine and hydrogen into the reaction space so that a silicon precursor is adsorbed on a surface of the substrate;
(b) exposing the substrate to purge gas and/or vacuum to remove excess silicon reactant and reaction byproducts;
(c) exposing the substrate to reactive species generated by a plasma from a nitrogen precursor; and
(d) exposing the substrate to purge gas and/or vacuum to remove excess reactive species and reaction byproducts;
wherein a thin film comprising silicon nitride of a desired thickness is formed; and
wherein the etch rate of the silicon nitride thin film in 0.5% aqueous HF is less than half the etch rate of thermal silicon oxide in 0.5% aqueous HF.
0 Assignments
0 Petitions
Accused Products
Abstract
Methods and precursors for depositing silicon nitride films by atomic layer deposition (ALD) are provided. In some embodiments the silicon precursors comprise an iodine ligand. The silicon nitride films may have a relatively uniform etch rate for both vertical and the horizontal portions when deposited onto three-dimensional structures such as FinFETS or other types of multiple gate FETs. In some embodiments, various silicon nitride films of the present disclosure have an etch rate of less than half the thermal oxide removal rate with diluted HF (0.5%).
309 Citations
24 Claims
-
1. A plasma enhanced atomic layer deposition method of depositing a silicon nitride thin film on a substrate in a reaction space, the method comprising a plurality of deposition cycles, each deposition cycle comprising:
-
(a) introducing a vapor-phase silicon reactant comprising iodine and hydrogen into the reaction space so that a silicon precursor is adsorbed on a surface of the substrate; (b) exposing the substrate to purge gas and/or vacuum to remove excess silicon reactant and reaction byproducts; (c) exposing the substrate to reactive species generated by a plasma from a nitrogen precursor; and (d) exposing the substrate to purge gas and/or vacuum to remove excess reactive species and reaction byproducts; wherein a thin film comprising silicon nitride of a desired thickness is formed; and wherein the etch rate of the silicon nitride thin film in 0.5% aqueous HF is less than half the etch rate of thermal silicon oxide in 0.5% aqueous HF. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A plasma enhanced atomic layer deposition method of depositing a silicon nitride thin film on a three dimensional structure on a substrate in a reaction space, the method comprising a plurality of deposition cycles comprising:
-
(a) providing a pulse of vapor phase SiI2H2 to the reaction space; (b) flowing a purge gas through the reaction space to remove excess vapor phase SiI2H2 and reaction byproducts; (c) flowing nitrogen gas to the reaction space; (d) generating a plasma in the nitrogen gas in the reaction chamber; and (e) flowing a purge gas through the reaction space to remove excess nitrogen plasma and reaction byproducts, wherein the three dimensional structure has vertical and horizontal portions, wherein the silicon nitride thin film has a step coverage of more than about 80% on the three-dimensional structure; and wherein the silicon nitride film has a uniform etch rate on the vertical and horizontal portions of the three dimensional structure. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23, 24)
-
Specification