Conformal damage-free encapsulation of chalcogenide materials

Patent metadata

Field	Value
Publication number	US-2022115592-A1
Application number	US-202117645178-A
Country	US
Kind code	A1
Filing date	Dec 20, 2021
Priority date	Aug 24, 2018
Publication date	Apr 14, 2022
Grant date	—

Abstract

Methods and apparatuses for forming an encapsulation bilayer over a chalcogenide material on a semiconductor substrate are provided. Methods involve forming a bilayer including a barrier layer directly on chalcogenide material deposited using pulsed plasma plasma-enhanced chemical vapor deposition (PP-PECVD) and an encapsulation layer over the barrier layer deposited using plasma-enhanced atomic layer deposition (PEALD). In various embodiments, the barrier layer is formed using a halogen-free silicon precursor and the encapsulation layer deposited by PEALD is formed using a halogen-containing silicon precursor and a hydrogen-free nitrogen-containing reactant.

First claim

What is claimed is:

1 . An apparatus for processing a substrate, the apparatus comprising:
an etch chamber configured to etch a semiconductor substrate having one or more layers of chalcogenide materials to form a pattern of chalcogenide materials in stacks on the semiconductor substrate; a deposition chamber configured to deposit encapsulation bilayer on the semiconductor substrate using pulsed plasma plasma-enhanced chemical vapor deposition (PP-PECVD) and plasma-enhanced atomic layer deposition (PEALD); and a wafer transfer tool configured to transfer the semiconductor substrate between the etch chamber and the deposition chamber without breaking vacuum.

2 . The apparatus of claim 1 , further comprising:
a controller configured with instructions for performing the following operations:
etching, in the etch chamber, the semiconductor substrate having the one or more layers of chalcogenide materials to form the pattern of chalcogenide materials; and
forming, in the deposition chamber, the encapsulation bilayer on the semiconductor substrate, wherein the etching and depositing occur without breaking vacuum.

3 . The apparatus of claim 2 , wherein the controller configured with instructions for forming the encapsulation bilayer comprises:
depositing a first silicon nitride layer on the pattern of chalcogenide materials in the deposition chamber by PP-PECVD; and depositing a second silicon nitride layer on the first silicon nitride layer in the deposition chamber by PEALD.

4 . The apparatus of claim 3 , wherein the second silicon nitride layer deposited by PEALD is deposited using alternating pulses of a chlorine-free halogen-containing silicon-containing precursor and a nitrogen-containing reactant.

5 . The apparatus of claim 4 , wherein the nitrogen-containing reactant is hydrogen-free and the chlorine-free halogen-containing silicon-containing precursor comprises iodine, bromine, or combinations thereof.

6 . The apparatus of claim 3 , wherein the first silicon nitride layer deposited by PP-PECVD is deposited using a halogen-free silane precursor and ammonia.

7 . The apparatus of claim 3 , wherein the first silicon nitride layer has a thickness between 5 Å and 10 Å on a sidewall of the pattern of chalcogenide materials.

8 . The apparatus of claim 3 , wherein the first silicon nitride layer deposited by PP-PECVD pulsed at a duty cycle between 5% and 20%.

9 . The apparatus of claim 3 , wherein the controller configured with instructions for forming the encapsulation layer is further configured with instructions for:
exposing the first silicon nitride layer to a post-treatment plasma to densify the first silicon nitride layer.

10 . The apparatus of claim 9 , further comprising:
a post-treatment chamber configured to perform the post-treatment plasma to densify the first silicon nitride layer, wherein etching, depositing, and exposing the first silicon nitride layer to the post-treatment plasma occur without breaking vacuum.

11 . The apparatus of claim 2 , wherein the controller configured with instructions for forming the encapsulation bilayer comprises:
depositing a first silicon nitride layer having a first film density on the pattern of chalcogenide materials in the deposition chamber; and depositing a second silicon nitride layer having a second film density on the first silicon nitride layer, wherein the first film density is less than the second film density.

12 . The apparatus of claim 11 , wherein the first silicon nitride layer is deposited by PP-PECVD in the deposition chamber and the second silicon nitride layer is deposited by PEALD in the deposition chamber.

13 . The apparatus of claim 11 , wherein the first film density is less than 2.5 g/cm 3 and the second film density is greater than 2.6 g/cm 3 .

14 . The apparatus of claim 1 , further comprising:
a clean chamber configured to clean the semiconductor substrate.

15 . The apparatus of claim 1 , further comprising:
a mini-transfer station positioned between the etch chamber and the deposition chamber.

16 . The apparatus of claim 1 , wherein the etch chamber is configured to be at a different pressure than a pressure of the deposition chamber.

Assignees

• Lam Res Corp

Inventors

• Sims James Samuel
• Mckerrow Andrew John
• Shen Meihua
• Lill Thorsten
• Tang Shane
• Kelchner Kathryn Merced
• Hoang John
• Dulkin Alexander
• Qian Danna
• Rai Vikrant

Classifications

• H10P72/0454

  surrounding a central transfer chamber · CPC title

• H10P14/69433

  the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz · CPC title

• H10P14/6686

  the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane · CPC title

• H10P14/6682

  the compound being a silane, e.g. disilane, methylsilane or chlorosilane · CPC title

• H10P14/6532

  by exposure to a plasma · CPC title