Selective deposition with atomic layer etch reset

Patent metadata

Field	Value
Publication number	US-2018308680-A1
Application number	US-201715581951-A
Country	US
Kind code	A1
Filing date	Apr 28, 2017
Priority date	Apr 19, 2017
Publication date	Oct 25, 2018
Grant date	—

Abstract

Methods are provided for conducting a deposition on a semiconductor substrate by selectively depositing a material on the substrate. The substrate has a plurality of substrate materials, each with a different nucleation delay corresponding to the material deposited thereon. Specifically, the nucleation delay associated with a first substrate material on which deposition is intended is less than the nucleation delay associated with a second substrate material on which deposition is not intended according to a nucleation delay differential, which degrades as deposition proceeds. A portion of the deposited material is etched to reestablish the nucleation delay differential between the first and the second substrate materials. The material is further selectively deposited on the substrate.

First claim

1 . A method of conducting a deposition on a semiconductor substrate, the method comprising:
selectively depositing a material on a semiconductor substrate, the substrate comprising a plurality of substrate materials having different nucleation delays corresponding to the material deposited thereon according to a nucleation delay differential; etching a portion of the material deposited on the substrate to reestablish the nucleation delay differential between the substrate materials; and further selectively depositing the material on the substrate.

2 . The method of claim 1 , wherein a nucleation delay associated with a first substrate material on which deposition is intended is less than a nucleation delay associated with a second substrate material on which deposition is not intended.

3 . The method of claim 2 , wherein the nucleation delay differential degrades as the deposition proceeds.

4 . The method of claim 1 , wherein the etching is performed in cycles, a cycle comprising exposing the substrate to an etching gas to modify a surface of the substrate; and exposing the substrate to a removal gas to remove at least some of the modified surface.

5 . The method of claim 1 , wherein the depositing is performed in cycles, a cycle comprising
exposing the substrate to a deposition precursor to modify a surface of the substrate; and exposing the substrate to a reducing agent to deposit the material.

6 . The method of claim 1 , wherein repeating the selectively depositing the material on the substrate and etching a portion of the deposited material thickens the material deposited without resulting in a corresponding breakdown of deposition selectivity.

7 . The method of claim 1 , wherein repeating the selectively depositing the material on the substrate and etching a portion of the deposited material prevents off-target deposition.

8 . The method of claim 1 , wherein the material to be deposited is aluminum nitride (AlN).

9 . The method of claim 1 , wherein the plurality of substrate materials are selected from a group consisting of silicon oxide (SiO 2 ), silicon nitride (Si 3 N 4 ), silicon carbide (SiC), aluminum oxide (Al 2 O 3 ), and aluminum nitride (AlN).

10 . The method of claim 1 , wherein the plurality of substrate materials is selected from a group consisting of hafnium (Hf), zirconium (Zr) and tin oxide (SnO 2 ).

11 . The method of claim 1 , wherein the plurality of substrate materials are selected from a group of conducting films consisting of tungsten (W), copper (Cu), cobalt (Co), aluminum (Al), titanium (Ti), silicon (Si) and carbon (C).

12 . The method of claim 8 , wherein trimethylaluminum provides aluminum for the aluminum nitride to be deposited.

13 . A method comprising:
(a) exposing a substrate housed in a chamber to alternating pulses of a first reactant and a second reactant to deposit a film over the substrate, the substrate having a first substrate material on which deposition of the film is intended and a second substrate material on which deposition of the film is not intended, the second substrate material being different from the first substrate material, and the nucleation delay for the first substrate material being less than the nucleation delay for the second substrate material according to a nucleation delay differential, which degrades upon proceeding with the deposition; (b) exposing a substrate housed in a chamber to alternating pulses of an etching gas and a removal gas to etch a portion of the deposited material to reset the nucleation delay differential between the first and second substrate materials

14 . The method of claim 13 further comprising repeating (a) and (b) in the same chamber.

15 . An apparatus for processing substrates, the apparatus comprising:
one or more process chambers, each process chamber having a chuck; one or more gas inlets into the process chambers and associated flow-control hardware; and a controller having a processor and a memory, wherein
the processor and the memory are communicatively connected with one another,
the at least one processor is at least operatively connected with the flow-control hardware, and
the memory stores computer-executable instructions for controlling the at least one processor to at least control the flow-control hardware by:
selectively depositing a material on a semiconductor substrate, the substrate comprising a plurality of substrate materials having different nucleation delays corresponding to the material deposited thereon according to a nucleation delay differential;
etching a portion of the material deposited on the substrate to reestablish the nucleation delay differential between the substrate materials; and
further selectively depositing the material on the substrate.

16 . The apparatus of claim 15 , wherein the selectively depositing a material on a semiconductor substrate and etching a portion of the material deposited on the substrate are performed without breaking vacuum.

17 . The apparatus of claim 15 wherein
the memory stores computer-executable instructions for controlling the at least one processor to at least control the flow-control hardware by:
(a) exposing a substrate housed in a chamber to alternating pulses of a first reactant and a second reactant to deposit a film over the substrate, the substrate having a first substrate material on which deposition of the film is intended and a second substrate material on which deposition of the film is not intended, the second substrate material being different from the first substrate material, and the nucleation delay for the first substrate material being less than the nucleation delay for the second substrate material according to a nucleation delay differential, which degrades upon proceeding with the deposition;
(b) exposing a substrate housed in a chamber to alternating pulses of an etching gas and a removal gas to etch a portion of the deposited material to reset the nucleation delay differential between the first and second substrate materials

18 . The apparatus of claim 17 further comprising repeating (a) and (b) in the same chamber.

19 . The apparatus of claim 17 , wherein the (a) and (b) are performed without breaking vacuum.

Assignees

• Lam Res Corp

Inventors

• Reddy Kapu Sirish
• Rainville Meliha Gozde
• Shankar Nagraj
• Hausmann Dennis M
• Smith David Charles
• Sivaramakrishnan Karthik
• Porter David W

Classifications

• H10P72/0466

  characterised by the construction of the load-lock chamber · CPC title

• H10P72/0454

  surrounding a central transfer chamber · CPC title

• H10P50/285

  of materials not containing Si, e.g. PZT or Al2O3 · CPC title

• H10P14/69391

  the material containing aluminium, e.g. Al2O3 · CPC title

• H10P14/6339 Primary

  deposition by cyclic CVD, e.g. ALD, ALE or pulsed CVD · CPC title