Etching apparatus

Patent metadata

Field	Value
Publication number	US-2022181162-A1
Application number	US-202217677752-A
Country	US
Kind code	A1
Filing date	Feb 22, 2022
Priority date	May 19, 2016
Publication date	Jun 9, 2022
Grant date	—

Abstract

An apparatus which selectively etches a first region with respect to a second region made of a material different from that of the first region. The apparatus is controlled to perform a first step for generating, in a processing container housing a workpiece to be treated, a plasma of a treatment gas from a gas supply including a fluorocarbon gas, an oxygen-containing gas, and an inert gas, and forming a deposit including fluorocarbon on the object to be treated, and a second step for etching the first region with radicals of the fluorocarbon included in the deposit. The apparatus is also controlled to perform the first step and the second step repeatedly.

First claim

1 . A substrate processing apparatus comprising:
at least one processing container; a substrate support inside the processing container which supports a substrate during processing; a port through which the substrate is transferred into the processing container; a first power supply which supplies a plasma generating power to the processing container at a first frequency; a second power supply which supplies a biasing power to the substrate support at a second frequency which is different from the first frequency; a gas supply configured to selectively supply a plurality of gases including a fluorocarbon gas, an oxygen gas, a hydrogen gas, and at least one of an inert gas or a noble gas; an exhaust device which includes a vacuum pump; and a controller; wherein the apparatus is configured to form a fluorocarbon deposit on the substrate, and after forming the fluorocarbon deposit, to perform an etching using fluorocarbon radicals of the deposit to etch the substrate at a location below the fluorocarbon deposit.

2 . The substrate processing apparatus according to claim 1 , further including a third power supply, wherein the third power supply is a DC power supply.

3 . The substrate processing apparatus according to claim 1 , wherein the controller is configured to control the forming of the fluorocarbon deposit and the etching such that the fluorocarbon deposit is formed on a side wall of a feature of the substrate during forming of the deposit, and during the etching, radicals from the fluorocarbon deposit on the side wall etch a bottom of the feature.

4 . The substrate processing apparatus according to claim 3 , wherein the controller is configured to control the gas supply to:
supply the fluorocarbon gas during the forming of the fluorocarbon deposit; supply the oxygen gas during the forming of the fluorocarbon deposit and stop the supply of the oxygen gas during the etching; and supply the at least one of an inert gas and a noble gas during the etching.

5 . The substrate processing apparatus according to claim 1 , wherein the controller is configured to control the apparatus to:
(a) receive the substrate on the substrate support having a first region and a second region, the second region including a recess, the first region filling the recess and also extending over and covering the second region, the substrate further including a mask above the first region, the mask having an opening width larger than an opening width of the recess; (b) perform a first etching through the mask in an upper portion of the first region to remove part of the upper portion of the first region and form an opening in the upper part of the first region at a location above the second region; (c) after the first etching, perform a selective etch of the first region such that, during the selective etch, a portion of the first region in the recess is etched, the selective etch including the controller being further configured to control the apparatus to:
(i) perform a first step using the fluorocarbon gas from the gas supply to form the fluorocarbon deposit on the substrate; and
(ii) after the first step, perform a second step of etching the first region in the recess in which the fluorocarbon radicals from the fluorocarbon deposit etch the first region in the recess to remove portions of the first region from the recess.

6 . The substrate processing apparatus according to claim 5 , wherein the controller is configured to stop the first etching before the second region is exposed, and
wherein during the selective etch, a portion of the fluorocarbon deposit is formed on a side wall of the first region and on the second region.

7 . A substrate processing apparatus comprising:
at least one processing container, a substrate support inside the processing container; a power supply; a gas supply; and a controller configured to control the apparatus to: (a) receive a substrate on the substrate support having a first region and a second region, the second region including a recess, the first region filling the recess and also extending over and covering the second region, the substrate further including a mask above the first region, the mask having an opening width larger than an opening width of the recess; (b) perform a first etching through the mask in an upper portion of the first region to remove part of the upper portion of the first region and form an opening in the upper part of the first region at a location above the second region; (c) after the first etching, perform a selective etch of the first region such that, during the selective etch, a portion of the first region in the recess is etched, the selective etch including the controller being further configured to control the apparatus to:
(i) perform a first step using a fluorocarbon gas from the gas supply to form a fluorocarbon deposit on the substrate; and
(ii) after the first step, perform a second step of etching the first region in the recess in which fluorocarbon radicals from the fluorocarbon deposit etch the first region in the recess to remove portions of the first region from the recess.

8 . The substrate processing apparatus according to claim 7 , wherein the controller is configured to:
stop the first etching prior to exposing the second region; supply the fluorocarbon gas and an oxygen gas during the first step, and further to supply at least one of an inert gas and a noble gas during the first step; and stop supply of the fluorocarbon gas and the oxygen gas during the second step while continuing to supply the at least one of an inert gas and a noble gas.

9 . The substrate processing apparatus according to claim 8 , wherein the power supply includes a first power supply having a first frequency which supplies a plasma generating power and a second power supply having a second frequency which supplies a biasing power, and the second frequency is different from the first frequency, and
wherein the controller is configured to control the first power supply and the second power supply to: provide a plasma generating power by the first power supply which is greater during the first etching than plasma generating power by the first power supply during the first step to form the fluorocarbon deposit; and provide a biasing power by the second power supply which is greater during the first etching than biasing power supplied by the second power supply during the first step to form the fluorocarbon deposit.

10 . The substrate processing apparatus according to claim 7 , wherein the controller is configured to control the gas supply to at least one of: (a) supply an oxygen gas during the first step and discontinue supply of the oxygen gas during the second step, or (b) supply the fluorocarbon gas during the first step and discontinue supply of the fluorocarbon gas during the second step.

11 . The substrate processing apparatus according to claim 7 , wherein the controller is configured to control the gas supply to:
supply the fluorocarbon gas and an oxygen gas, and at least one of an inert gas or a noble gas, during the first step; and discontinue supply of the fluorocarbon gas and the oxygen during the second step.

12 . The substrate processing apparatus according to claim 7 , wherein the controller is further configured to:
repeat the selective etch including repeatedly alternating the first step and the second step; and before the selective etch is first performed, perform the first etching and stopping the first etching prior to exposure of the second region such that when the selective etch is first performed a predetermined thickness of the first region is present on the second

Assignees

• Tokyo Electron Ltd

Inventors

• Tsuji Akihiro
• Honda Masanobu
• Watanabe Hikaru

Classifications

• H10P72/722

  Details of electrostatic chucks · CPC title

• H10P72/0421

  for drying etching · CPC title

• H10P76/2043

  using an anti-reflective coating · CPC title

• H10P76/405

  characterised by their composition, e.g. multilayer masks · CPC title

• H10P50/287

  by chemical means · CPC title