Techniques and apparatus for unidirectional hole elongation using angled ion beams

Patent metadata

Field	Value
Publication number	US-2020194271-A1
Application number	US-201916676857-A
Country	US
Kind code	A1
Filing date	Nov 7, 2019
Priority date	Dec 14, 2018
Publication date	Jun 18, 2020
Grant date	—

Abstract

A method of patterning a substrate. The method may include providing a cavity in a layer, disposed on the substrate, the cavity having a first length along a first direction and a first width along a second direction, perpendicular to the first direction, and wherein the layer has a first height along a third direction, perpendicular to the first direction and the second direction. The method may include depositing a sacrificial layer over the cavity in a first deposition procedure; and directing angled ions to the cavity in a first exposure, wherein the cavity is etched, and wherein after the first exposure, the cavity has a second length along the first direction, greater than the first length, and wherein the cavity has a second width along the second direction, no greater than the first width.

First claim

What is claimed is:

1 . A method of patterning a substrate, comprising:
providing a cavity in a layer, disposed on the substrate, the cavity having a first length along a first direction and a first width along a second direction, perpendicular to the first direction, and wherein the first layer has a first height along a third direction, perpendicular to the first direction and the second direction; depositing a sacrificial layer over the cavity in a first deposition procedure; and directing angled ions to the cavity in a first exposure, wherein the cavity is etched, and wherein after the first exposure, the cavity has a second length along the first direction, greater than the first length, and wherein the cavity has a second width along the second direction, no greater than the first width.

2 . The method of claim 1 , wherein the first layer retains the first height after the first exposure.

3 . The method of claim 2 , further comprising:
depositing a second sacrificial layer over the cavity in a second deposition procedure; and directing second angled ions to the cavity in a second exposure, wherein the cavity is etched, a nd wherein after the second exposure, the cavity has a third length along the first direction, greater than the second length, and wherein the cavity has a third width along the second direction, no greater than the first width.

4 . The method of claim 1 , wherein the angled ions are first angled ions, wherein the first angled ions are directed in a presence of a first reactive ambient, along a first trajectory at a first non-zero angle of incidence with respect to a perpendicular to a plane of the substrate, the first trajectory being aligned with the first direction.

5 . The method of claim 1 , wherein the angled ions are directed in a presence of a first reactive ambient, wherein the angled ions comprise:
a first angled ion beam having a first trajectory, at a first non-zero angle of incidence with respect to a perpendicular to a plane of the substrate; and a second angled ion beam having a second trajectory, at a second non-zero angle of incidence with respect to a perpendicular to a plane of the substrate, wherein the first trajectory and the second trajectory are aligned with the first direction, and opposite to one another.

6 . The method of claim 5 , wherein the first angled ion beam and the second angled ion beam comprise a first ribbon beam and a second ribbon beam, respectively.

7 . The method of claim 1 , wherein the depositing the sacrificial layer comprises:
generating a plasma in a plasma chamber, including a depositing species; and providing an extraction aperture along a side of the plasma chamber, wherein the depositing species diffuse through the extraction aperture to the substrate.

8 . The method of claim 7 , wherein the directing angled ions to the cavity in the first exposure comprises directing the angled ions through the extraction aperture.

9 . A method of patterning a substrate, comprising:
providing a cavity in a first layer, disposed on the substrate, the cavity having a first length along a first direction and a first width along a second direction, perpendicular to the first direction, and wherein the first layer has a first height along a third direction, perpendicular to the first direction and the second direction; depositing a sacrificial layer over the cavity in a first deposition procedure; and directing angled ions to the cavity in a first exposure, wherein the angled ions comprise: a first angled ion beam having a first trajectory, directed to a first sidewall of the cavity; and a second angled ion beam having a second trajectory, directed to a second sidewall of the cavity, opposite the first sidewall, wherein the cavity is etched, and wherein after the first exposure, the cavity has a second length along the first direction, greater than the first length, and wherein the cavity has a second width along the second direction, no greater than the first width.

10 . The method of claim 9 , wherein the first layer retains the first height after the first exposure.

11 . The method of claim 9 , wherein the first angled ion beam and the second angled ion beam comprise a first ribbon beam and a second ribbon beam, respectively.

12 . The method of claim 9 , wherein the first layer comprises a hard mask layer, and wherein the sacrificial layer comprises a polymer layer.

13 . The method of claim 9 , wherein the depositing the sacrificial layer and the directing the angled ions comprises a first etch cycle, the method comprising repeating the first etch cycle at least once in a plurality of etch cycles,
wherein after the plurality of etch cycles, the cavity has a third length along the first direction, greater than the second length, and wherein the cavity has a third width along the second direction, no greater than the first width.

14 . The method of claim 13 , wherein a thickness loss of the first layer after the plurality of etch cycles is less than 10%.

15 . The method of claim 9 , wherein the first angled ion beam and the second angled ion beam comprise a first ribbon beam and a second ribbon beam, elongated along the second direction.

16 . The method of claim 15 , further comprising scanning the substrate along the first direction during the first exposure.

17 . An apparatus, comprising;
a loadlock to receive a substrate; a transfer chamber, coupled to the loadlock, and arranged to transfer the substrate under vacuum; an angled ion beam etch station, coupled to the transfer chamber, to direct a reactive angled ion beam to the substrate at a non-zero angle of incidence with respect to a normal to a substrate plane; a a polymer deposition chamber, coupled to the transfer chamber, arranged to deposit a polymer layer on the substrate; and a controller, coupled to the polymer deposition chamber, the transfer chamber and the angled ion beam etch station, to cycle the substrate over a plurality of etch cycles, wherein a given etch cycle comprises deposition of the polymer layer in the polymer deposition chamber, etching of the substrate in the angled ion beam etch station, and transporting the substrate between the polymer deposition chamber and the angled ion beam etch station via the transfer chamber.

18 . The apparatus of claim 17 , the angled ion beam etch station comprising:
a plasma chamber for generating a plasma therein; extraction plate, disposed along a side of the plasma chamber, and including an extraction aperture to direct the angled reactive ion beam to the substrate; and a substrate stage, disposed to scan the substrate with respect to the angled reactive ion beam along a first direction.

19 . The apparatus of claim 18 , the extraction aperture being elongated along a second direction, perpendicular to the first direction.

Assignees

• Applied Materials Inc

Inventors

• Anglin Kevin
• Ruffell Simon

Classifications

• H10P72/0471

  comprising at least one ion or electron beam chamber · CPC title

• H10P72/0468

  comprising a chamber adapted to a particular process · CPC title

• H10P72/0466

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

• H10P72/0464

  characterised by the construction of the transfer chamber · CPC title

• H10P72/0454

  surrounding a central transfer chamber · CPC title