Methods of encapsulation

Patent metadata

Field	Value
Publication number	US-10566186-B2
Application number	US-201816179809-A
Country	US
Kind code	B2
Filing date	Nov 2, 2018
Priority date	May 6, 2016
Publication date	Feb 18, 2020
Grant date	Feb 18, 2020

Abstract

Methods and apparatuses suitable for depositing low hydrogen content, hermetic, thin encapsulation layers at temperatures less than about 300° C. are provided herein. Methods involve pulsing plasma while exposing a substrate to deposition reactants, and post-treating deposited encapsulation films to densify and reduce hydrogen content. Post-treatment methods include periodic exposure to inert plasma without reactants and exposure to ultraviolet radiation at a substrate temperature less than about 300° C.

First claim

What is claimed is:

1. A method of encapsulating a memory device on a substrate in a process chamber, the method comprising:
exposing the substrate having the memory device housed in the process chamber to a deposition precursor at a substrate temperature less than 300° C.; and
generating a reactive species in a remote plasma generator;
introducing the reactive species to the process chamber to react with the deposition precursor to deposit an encapsulation layer over the memory device; and
exposing the encapsulation layer to a post-treatment process to form a hermetic encapsulation layer.

2. The method of claim 1 , wherein the post-treatment process is performed at a temperature less than 300° C.

3. The method of claim 1 , wherein the encapsulation layer is selected from the group consisting of silicon nitride, undoped silicon carbide, oxygen-doped silicon carbide, germanium nitride, undoped germanium carbide, and oxygen-doped germanium carbide.

4. The method of claim 1 , wherein the encapsulation layer is deposited by remote plasma enhanced chemical vapor deposition.

5. The method of claim 4 , wherein remote plasma enhanced chemical vapor deposition comprises:
(a) flowing a reactant to a remote plasma-generating region and igniting the plasma to generate the reactive species comprising reactant radicals;
(b) introducing the reactant radicals through a showerhead to the substrate; and
(c) introducing the deposition precursor downstream of the showerhead to the substrate while introducing the reactant radicals.

6. The method of claim 1 , wherein the post-treatment process comprises exposing the substrate to a post-treatment gas and igniting a second plasma without a reactant.

7. The method of claim 6 , wherein the substrate is exposed to the post-treatment gas and the second plasma for a duration between about 10 seconds and about 50 seconds.

8. The method of claim 6 , wherein the post-treatment gas is selected from the group consisting of nitrogen, ammonia, helium, argon, and combinations thereof.

9. The method of claim 1 , wherein the memory device is a magnetoresistive random-access memory.

10. The method of claim 1 , wherein the memory device comprises a magnetic tunnel junction.

11. The method of claim 1 , wherein the encapsulation layer is deposited to a thickness between about 50 Å and about 500 Å.

12. The method of claim 1 , wherein the encapsulation layer is deposited by plasma enhanced chemical vapor deposition.

13. The method of claim 1 , wherein the encapsulation layer deposited over the memory device has a step coverage between about 70% and about 90%.

14. The method of claim 1 , wherein the encapsulation layer is a silicon nitride film deposited by exposing the substrate to a silicon-containing precursor and a nitrogen-containing reactant.

15. The method of claim 1 , wherein the encapsulation layer is a silicon oxycarbide film deposited by exposing the substrate to a silicon-and carbon-and-oxygen-containing precursor and hydrogen.

16. The method of claim 1 , further comprising prior to depositing the encapsulation layer, heating the substrate to a temperature of about 300° C.

17. The method of claim 1 , wherein the reactive species comprises nitrogen and an inert gas.

Assignees

• Lam Res Corp

Inventors

• Van Schravendijk Bart J
• Singhal Akhil
• Wei Joseph Hung-chi
• Varadarajan Bhadri N
• Mclaughlin Kevin
• Holder Casey
• Banerji Ananda

Classifications

• C23C16/50

  using electric discharges {(generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34)} · CPC title

• C23C16/345

  Silicon nitride · CPC title

• H01J37/3244

  Gas supply means · CPC title

• H01J2237/334

  Etching · CPC title

• H01J37/32082

  Radio frequency generated discharge (H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence) · CPC title