Sacrificial-film removal method and substrate processing device

Patent metadata

Field	Value
Publication number	US-2016254162-A1
Application number	US-201415032516-A
Country	US
Kind code	A1
Filing date	Oct 27, 2014
Priority date	Oct 30, 2013
Publication date	Sep 1, 2016
Grant date	—

Abstract

The present invention is a sacrificial-film removal method of removing a sacrificial film from a surface of a substrate provided with a plurality of struts and the sacrificial film embedded between the plurality of struts, including: a wet etching step where the sacrificial film is removed to its halfway depth by supplying an etchant to the surface of the substrate; a rinse step where a residue adhering to the surface of the substrate is washed out by supplying a rinsing liquid to the surface of the substrate after the wet etching step; a drying step where a liquid component on the surface of the substrate is removed after the rinse step; and a dry etching step where the sacrificial film remaining on the surface of the substrate is removed by supplying an etching gas to the surface of the substrate after the drying step.

First claim

1 . A sacrificial-film removal method of removing a sacrificial film from a surface of a substrate provided with a plurality of struts and the sacrificial film embedded between the plurality of struts, including:
a wet etching step where the sacrificial film is removed to its halfway depth by supplying an etchant to the surface of the substrate; a rinse step where a residue adhering to the surface of the substrate is washed out by supplying a rinsing liquid to the surface of the substrate after the wet etching step; a drying step where a liquid component on the surface of the substrate is removed after the rinse step; and a dry etching step where the sacrificial film remaining on the surface of the substrate is removed by supplying an etching gas to the surface of the substrate after the drying step.

2 . The sacrificial-film removal method according to claim 1 , further including a low-surface-tension liquid displacing step where the rinsing liquid on the surface of the substrate is displaced with a low-surface-tension liquid whose surface tension is lower than that of the rinsing liquid by supplying the low-surface-tension liquid to the surface of the substrate after the rinse step and prior to the drying step.

3 . The sacrificial-film removal method according to claim 1 , wherein a supporting film supporting the plurality of struts is further formed on the surface of the substrate, the supporting film is provided with a plurality of hole portions, and removal by the etchant is started from portions of the sacrificial film corresponding to the plurality of hole portions in the wet etching step.

4 . The sacrificial-film removal method according to claim 3 , wherein a natural oxide film is formed on a surface of the supporting film, and the method further including:
a preprocessing step where the natural oxide film formed on the surface of the supporting film is removed prior to the wet etching step.

5 . A substrate processing apparatus, including:
a substrate holding unit holding a substrate provided with a plurality of struts and a sacrificial film embedded between the plurality of struts; an etchant supply unit for supplying an etchant to the substrate held by the substrate holding unit; an etching gas supply unit for supplying an etching gas to the substrate held by the substrate holding unit; a rinsing liquid supply unit for supplying a rinsing liquid to the substrate held by the substrate holding unit; a substrate rotating unit for rotating the substrate held by the substrate holding unit; and a control unit controlling the etchant supply unit, the etching gas supply unit, the rinsing liquid supply unit and the substrate rotating unit, wherein the control unit performs a wet etching step where the sacrificial film is removed to its halfway depth by supplying an etchant to the surface of the substrate, a rinse step where a residue adhering to the surface of the substrate is washed out by supplying a rinsing liquid to the surface of the substrate after the wet etching step, a drying step where a liquid component on the surface of the substrate is removed after the rinse step, and a dry etching step where the sacrificial film remaining on the surface of the substrate is removed by supplying an etching gas to the surface of the substrate after the drying step.

6 . The substrate processing apparatus according to claim 5 , wherein the substrate holding unit includes a first substrate holding unit holding the substrate, and a second substrate holding unit holding the substrate,
the substrate processing apparatus further includes: a wet processing chamber for performing a wet etching treatment using an etchant to the substrate; and a dry processing chamber provided in a manner separated from the wet processing chamber for performing a dry etching treatment using an etching gas to the substrate after the wet etching treatment, the wet processing chamber accommodates the first substrate holding unit, the substrate rotating unit, the etchant supply unit and the rinsing liquid supply unit, and the dry processing chamber accommodates the second substrate holding unit and the etching gas supply unit.

7 . The substrate processing apparatus according to claim 5 , further including a processing chamber collectively accommodating the substrate holding unit, the substrate rotating unit, the etchant supply unit, the rinsing liquid supply unit and the etching gas supply unit.

8 . The substrate processing apparatus according to claim 5 , further including a low-surface-tension liquid supply unit for supplying a low-surface-tension liquid whose surface tension is lower than that of the rinsing liquid to the substrate held by the substrate holding unit, wherein
the control unit performs a low-surface-tension liquid displacing step where the rinsing liquid on the surface of the substrate is displaced with the low-surface-tension liquid by supplying the low-surface-tension liquid to the surface of the substrate after the rinse step and prior to the drying step.

9 . The substrate processing apparatus according to claim 8 , wherein the substrate holding unit includes a first substrate holding unit holding the substrate, and a second substrate holding unit holding the substrate,
the substrate processing apparatus further includes: a wet processing chamber for performing a wet etching treatment using an etchant to the substrate; and a dry processing chamber provided in a manner separated from the wet processing chamber for performing a dry etching treatment using an etching gas to the substrate after the wet etching treatment, the wet processing chamber accommodates the first substrate holding unit, the substrate rotating unit, the etchant supply unit, the rinsing liquid supply unit and the low-surface-tension liquid supply unit, and the dry processing chamber accommodates the second substrate holding unit and the etching gas supply unit.

10 . The substrate processing apparatus according to claim 8 , further including a processing chamber collectively accommodating the substrate holding unit, the substrate rotating unit, the etchant supply unit, the rinsing liquid supply unit, the low-surface-tension liquid supply unit and the etching gas supply unit.

Assignees

• Screen Holdings Co Ltd
• Central Glass Co Ltd

Inventors

• Okutani Manabu
• Umezaki Tomonori
• Kikuchi Akiou

Classifications

• H10P72/0406

  for cleaning followed by drying, rinsing, stripping, blasting or the like · CPC title

• H10P70/23

  during, before or after processing of insulating materials · CPC title

• H10P70/20 Primary

  Cleaning during device manufacture · CPC title

• H10P50/667 Primary

  by liquid etching only · CPC title

• H10P50/266

  by vapour etching only · CPC title