Method for etching an etch layer

A method of etching features in a stack comprising a dielectric material below a mask on a substrate, the method comprising:

• (a) generating an etch plasma from an etch gas, exposing the stack to the etch plasma, and partially etching features in the stack in a plasma processing chamber;
• (b) after (a) providing a deposition process performed in-situ in the plasma processing chamber to deposit a protective film comprising a plurality of cycles, wherein each cycle comprises:
• (i) exposing the stack to a first reactant gas comprising WF6, wherein the first reactant gas is adsorbed onto the stack;
• and
• (ii) exposing the stack to a plasma formed from a second reactant gas, wherein the plasma formed from the second reactant gas reacts with adsorbed first reactant gas to form the protective film over the stack, wherein the second reactant gas comprises an oxygen containing component to provide oxidation, wherein the deposition process further comprises maintaining a stack temperature below 150° C., wherein the providing the deposition provides a nonconformal atomic layer deposition process performed in-situ in the plasma processing chamber to deposit a nonconformal protective film that does not extend to bottoms of the features.