Substrate processing method, substrate processing apparatus and recording medium

Patent metadata

Field	Value
Publication number	US-2020279752-A1
Application number	US-202016802936-A
Country	US
Kind code	A1
Filing date	Feb 27, 2020
Priority date	Mar 1, 2019
Publication date	Sep 3, 2020
Grant date	—

Abstract

A substrate processing method includes etching a substrate having a first film and a second film at a first etching rate; changing an etching rate from the first etching rate to a second etching rate; and etching the substrate at the second etching rate.

First claim

We claim:

1 . A substrate processing method, comprising:
etching a substrate having a first film and a second film at a first etching rate; changing an etching rate from the first etching rate to a second etching rate; and etching the substrate at the second etching rate.

2 . The substrate processing method of claim 1 ,
wherein the second etching rate is lower than the first etching rate.

3 . The substrate processing method of claim 2 ,
wherein, in the etching of the substrate at the first etching rate and the etching of the substrate at the second etching rate, the substrate is etched by supplying a chemical liquid containing multiple components to the substrate, and in the changing of the etching rate, the etching rate is lowered from the first etching rate to the second etching rate by changing a mixing ratio of the multiple components.

4 . The substrate processing method of claim 3 ,
wherein the first film is any one of a tungsten film, a molybdenum film, an osmium film, an iridium film, a ruthenium film, a rhodium film, a copper film and a nickel film, the second film is any one of a titanium nitride film and a tantalum nitride film, the chemical liquid contains phosphoric acid, acetic acid, nitric acid and water, and in the changing of the etching rate, the etching rate of the first film is lowered from the first etching rate to the second etching rate by lowering a mixing ratio of the water in the chemical liquid.

5 . The substrate processing method of claim 4 ,
wherein, in the etching of the substrate at the first etching rate and the etching of the substrate at the second etching rate, the substrate is etched by immersing the substrate in the chemical liquid stored in a processing tub, and in the changing of the etching rate, the etching rate is lowered from the first etching rate to the second etching rate by draining some of the chemical liquid from the processing tub and supplying a new chemical liquid having a lower mixing ratio of the water than the drained chemical liquid into the processing tub.

6 . The substrate processing method of claim 5 ,
wherein the second film is covered by the first film, in the etching of the substrate at the first etching rate, the first film is etched at the first etching rate, and in the changing of the etching rate, the etching rate of the first film is lowered from the first etching rate to the second etching rate before the second film is exposed through the first film.

7 . The substrate processing method of claim 4 ,
wherein the second film is covered by the first film, in the etching of the substrate at the first etching rate, the first film is etched at the first etching rate, and in the changing of the etching rate, the etching rate of the first film is lowered from the first etching rate to the second etching rate before the second film is exposed through the first film.

8 . The substrate processing method of claim 3 ,
wherein the second film is covered by the first film, in the etching of the substrate at the first etching rate, the first film is etched at the first etching rate, and in the changing of the etching rate, the etching rate of the first film is lowered from the first etching rate to the second etching rate before the second film is exposed through the first film.

9 . The substrate processing method of claim 2 ,
wherein, in the etching of the substrate at the first etching rate and the etching of the substrate at the second etching rate, the substrate is etched by supplying a chemical liquid to the substrate, and in the changing of the etching rate, the etching rate is lowered from the first etching rate to the second etching rate by changing a temperature of the chemical liquid from a first temperature to a second temperature lower than the first temperature.

10 . The substrate processing method of claim 9 ,
wherein the second film is covered by the first film, in the etching of the substrate at the first etching rate, the first film is etched at the first etching rate, and in the changing of the etching rate, the etching rate of the first film is lowered from the first etching rate to the second etching rate before the second film is exposed through the first film.

11 . The substrate processing method of claim 2 ,
wherein the second film is covered by the first film, in the etching of the substrate at the first etching rate, the first film is etched at the first etching rate, and in the changing of the etching rate, the etching rate of the first film is lowered from the first etching rate to the second etching rate before the second film is exposed through the first film.

12 . The substrate processing method of claim 2 ,
wherein, in the etching of the substrate at the first etching rate, the substrate is immersed in a first processing tub configured to store a first chemical liquid having the first etching rate as the etching rate, in the etching of the substrate at the second etching rate, the substrate is immersed in a second processing tub configured to store a second chemical liquid having the second etching rate as the etching rate, and in the changing of the etching rate, the etching rate is lowered from the first etching rate to the second etching rate by moving the substrate from the first processing tub to the second processing tub.

13 . A substrate processing apparatus, comprising:
a supply configured to supply a chemical liquid to a substrate having a first film and a second film; a change unit configured to change supply conditions of the chemical liquid supplied from the supply; and a controller configured to perform a first etching processing of etching the substrate with the chemical liquid at a first etching rate, a change processing of changing an etching rate to a second etching rate different from the first etching rate by controlling the change unit, and a second etching processing of etching the substrate with the chemical liquid at the second etching rate.

14 . The substrate processing apparatus of claim 13 ,
wherein the chemical liquid contains multiple components, the change unit changes a mixing ratio of the multiple components in the chemical liquid, and the controller controls the change unit to change the mixing ratio of the multiple components and lower the etching rate from the first etching rate to the second etching rate.

15 . The substrate processing apparatus of claim 13 ,
wherein the change unit changes a temperature of the chemical liquid, and the controller lowers the etching rate from the first etching rate to the second etching rate by controlling the change unit to change the temperature of the chemical liquid from a first temperature to a second temperature lower than the first temperature.

16 . The substrate processing apparatus of claim 13 , further comprising:
a first processing tub configured to store, as the chemical liquid, a first chemical liquid having the first etching rate as the etching rate; and a second processing tub configured to store, as the chemical liquid, a second chemical liquid having the second etching rate as the etching rate, wherein the supply includes: a first chemical liquid supply configured to supply the first chemical liquid into the first processing tub; and a second chemical liquid supply configured to supply the second chemical liquid into the second processing tub, and wherein the change unit is a moving mechanism configured to move the substrate from the first processing tub to the second processing tub.

17 . A computer-reada

Assignees

• Tokyo Electron Ltd

Inventors

• Honda Takumi
• Kagawa Koji

Classifications

• H10P72/0426 Primary

  with the semiconductor substrates being dipped in baths or vessels · CPC title

• H10P50/642

  Chemical etching · CPC title

• H10P50/667 Primary

  by liquid etching only · CPC title

• H10P72/0604

  Process monitoring, e.g. flow or thickness monitoring · CPC title

• H10P72/0402

  Apparatus for fluid treatment (H10P72/0441, H10P72/0448 take precedence) · CPC title