Patent ID: 9564309
Date: 2017-02-07
CPC Classifications: H01L

Claim:
1. A plasma enhanced atomic layer deposition (PEALD) method of depositing a silicon nitride thin film on a substrate in a reaction space comprising: (a) introducing a vapor-phase silicon reactant into the reaction space so that the silicon precursor is adsorbed to a surface of the substrate; (b) removing excess silicon reactant and reaction byproducts; (c) contacting the adsorbed silicon reactant with a reactive species generated by a plasma from a nitrogen precursor; (d) removing excess reactive species and reaction byproducts; wherein nitrogen is flowed continuously to the reaction space throughout steps (a)-(d) and steps (a) through (d) are repeated until a silicon nitride film of a desired thickness is formed; wherein the silicon reactant is H wherein the silicon nitride thin film is deposited on at least one three-dimensional feature, and wherein a ratio of an etch rate of the silicon nitride thin film in 0.5% aqueous HF in a sidewall of the at least one three-dimensional feature to an etch rate of the silicon nitride thin film in 0.5% aqueous HF on a top surface of the at least one three-dimensional feature is less than 2.