Patent ID: 9373500
Filing Date: 2016-06-21
CPC Classification: C23C,H01J,H01L

Claim Text:
1. A method of depositing a titanium dioxide encapsulation layer over memory stacks on a semiconductor substrate, comprising: (a) receiving a substrate having a plurality of magnetoresistive random access memory (MRAM) stacks or phase change random access memory (PCRAM) stacks thereon in a reaction chamber; (b) flowing a titanium-containing reactant into the reaction chamber and allowing the titanium-containing reactant to adsorb onto the surface of the substrate; (c) flowing an oxygen-containing reactant into the reaction chamber and allowing the oxygen-containing reactant to adsorb onto the surface of the substrate; (d) exposing the reaction chamber to plasma for a duration of about 0.5 seconds or less to drive a surface reaction between the titanium-containing reactant and the oxygen-containing reactant to thereby conformally deposit a titanium dioxide encapsulation layer over the plurality of MRAM stacks or PCRAM stacks, wherein the plasma is generated using an RF power density of about 1750 W/m (e) repeating (b)-(d) until the encapsulation layer reaches a final thickness; (f) after (e), flowing a second titanium-containing reactant into the reaction chamber and allowing the second titanium-containing reactant to adsorb onto the surface of the substrate; (g) flowing a second oxygen-containing reactant into the reaction chamber and allowing the second oxygen-containing reactant to adsorb onto the surface of the substrate; (h) exposing the reaction chamber to a second plasma to drive a second surface reaction between the second titanium-containing reactant and the second oxygen-containing reactant to thereby conformally deposit a titanium dioxide second encapsulation layer over the encapsulation layer, wherein the second encapsulation layer is deposited under different plasma conditions than the encapsulation layer; and (i) repeating (f)-(h) until the second encapsulation layer reaches a second final thickness.