Predicting ultraviolet ray damage with visible wavelength spectroscopy during a semiconductor manufacturing process

• US 9,287,097 B2
• Filed: 11/13/2012
• Issued: 03/15/2016
• Est. Priority Date: 11/30/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kuboi, Nobuyuki, Tatsumi, Tetsuya, Fukasawa, Masanaga
• Primary Examiner(s): Shah, Kamini S
• Assistant Examiner(s): Hann, Jay B
• Application Number:
  US13/675,751
• Publication Number:
  US 20130133832A1
• Time in Patent Office: 1,218 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G01J 1/429 applied to measurement of ultraviolet light using counting tubes G01T
• CPC Class Codes: G06F 2111/10 Numerical modelling
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30
• CPC Class Codes: H01J 37/32963 End-point detection
• CPC Class Codes: H01J 37/32972 Spectral analysis
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching

Abstract

The simulation method is for predicting a damage amount due to ultraviolet rays in manufacturing a semiconductor device. The method includes: calculating particle density by performing simulation based on a differential equation for the particle density; calculating emission intensity at each wavelength in a visible wavelength region based on the calculated particle density; obtaining an electron energy distribution function by comparing the calculated emission intensity at each wavelength in the visible wavelength region with an actually detected emission spectrum in the visible wavelength region with reference to information on emission species and an emission wavelength in a target manufacturing process; predicting an emission spectrum in an ultraviolet wavelength region by using the electron energy distribution function and a reaction cross-sectional area relating to the emission species; and predicting a damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region.

Claims

1. A method for controlling a semiconductor manufacturing apparatus, the method comprising:

detecting an emission spectrum of light in a visible wavelength region emitted in the semiconductor manufacturing apparatus;

calculating particle density by performing simulation based on a differential equation for the particle density;

calculating emission intensity at each wavelength in a visible wavelength region based on the calculated particle density;

obtaining an electron energy distribution function by comparing the calculated emission intensity at each wavelength in the visible wavelength region with the detected emission spectrum with reference to information on emission species and an emission wavelength in a target manufacturing process;

predicting an emission spectrum of light emitted in the semiconductor manufacturing apparatus in an ultraviolet wavelength region by calculating emission intensity at each wavelength in the ultraviolet wavelength region by using the electron energy distribution function and a reaction cross-sectional area relating to the emission species;

predicting the damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region; and

controlling process conditions of the semiconductor manufacturing apparatus based on the predicted damage amount.

2. The method according to claim 1,

wherein the damage amount due to the ultraviolet rays is predicted based on the predicted emission spectrum in the ultraviolet wavelength region and created pattern structure data.

3. The method according to claim 2,

wherein a damage amount database in which a film material, an ultraviolet wavelength, a pattern structure, a dose amount of the ultraviolet rays, and process conditions are associated with the damage amount is created in advance, and cross-checking with the damage amount database is performed in predicting the damage amount due to the ultraviolet rays.

4. A non-transitory computer readable medium storing a program for controlling a semiconductor manufacturing apparatus, the program causing an information processing apparatus, when mounted thereon, to execute operations of:

detecting an emission spectrum of light in a visible wavelength region emitted in the semiconductor manufacturing apparatus;

calculating particle density by performing simulation based on a differential equation for the particle density;

calculating emission intensity at each wavelength in a visible wavelength region based on the calculated particle density;

obtaining an electron energy distribution function by comparing the calculated emission intensity at each wavelength in the visible wavelength region with the detected emission spectrum with reference to information on emission species and an emission wavelength in a target manufacturing process;

predicting an emission spectrum of light emitted in the semiconductor manufacturing apparatus in an ultraviolet wavelength region by calculating emission intensity at each wavelength in the ultraviolet wavelength region by using the electron energy distribution function and a reaction cross-sectional area relating to the emission species;

predicting the damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region; and

controlling process conditions of the semiconductor manufacturing apparatus based on the predicted damage amount.

5. A semiconductor manufacturing apparatus comprising:

a chamber in which a wafer is disposed;

a sensor that detects an emission spectrum of light emitted in a visible wavelength region inside the chamber; and

a calculation unit that;

calculates particle density by performing simulation based on a differential equation for the particle density,

calculates emission intensity at each wavelength in the visible wavelength region based on the calculated particle density,

obtains an electron energy distribution function by comparing the calculated emission intensity at each wavelength in the visible wavelength region with the detected emission spectrum, with reference to information on emission species and an emission wavelength in a target, manufacturing process,

predicts an emission spectrum in an ultraviolet wavelength region by using the electron energy distribution function and a reaction cross-sectional area relating to the emission species,

predicts a damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region, and

calculates target process conditions inside the chamber based on the damage amount,

wherein process conditions inside the chamber are set so as to meet the target process conditions that have been calculated by the calculation unit.

6. The semiconductor manufacturing apparatus according to claim 5,

wherein the calculation unit predicts a variation in a shape during a process by shape simulation after predicting the damage amount due to the ultraviolet rays and calculating the target process conditions inside the chamber and calculates updated target process conditions that are different from the previously calculated target process conditions when the variation in the shape exceeds a predetermined range.

7. The semiconductor manufacturing apparatus according to claim 5,

wherein the calculation unit further detects a termination point of overetching after main etching when the predicted damage amount due to the ultraviolet rays reaches a preset damage amount.

8. A method for controlling a semiconductor manufacturing device, the method comprising:

obtaining an equation for predicting emission intensity at each wavelength in an ultraviolet wavelength region that has been associated with an emission spectrum in a visible wavelength region, the equation having been calculated based on multivariable analysis;

detecting an emission spectrum of light emitted in the semiconductor manufacturing apparatus in the visible wavelength region;

predicting an emission spectrum of light emitted in the semiconductor manufacturing apparatus in the ultraviolet wavelength region by using the calculated predicting equation and the detected emission spectrum;

predicting the damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region; and

controlling process conditions of the semiconductor manufacturing apparatus based on the predicted damage amount.

9. The method according to claim 8,

wherein the damage amount due to the ultraviolet rays is predicted based on the predicted emission spectrum in the ultraviolet wavelength region and created pattern structure data.

10. The method according to claim 9,

wherein a damage amount database in which a film material, an ultraviolet wavelength, a pattern structure, a dose amount of the ultraviolet rays, and process conditions are associated with the damage amount is created in advance, and cross-checking with the damage amount database is performed in predicting the damage amount due to the ultraviolet rays.

11. A non-transitory computer readable medium storing a program for controlling a semiconductor manufacturing device, the program causing an information processing apparatus, when mounted thereon, to execute operations of:

obtaining an equation tier predicting emission intensity at each wavelength in an ultraviolet wavelength region that has been associated with an emission spectrum in a visible wavelength region, the equation having been calculated based on multivariable analysis;

detecting an emission spectrum of light emitted in the semiconductor manufacturing apparatus in the visible wavelength region;

predicting an emission spectrum of light emitted in the semiconductor manufacturing apparatus in the ultraviolet wavelength region by using the calculated predicting equation and the detected emission spectrum; and

predicting a damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region; and

controlling process conditions of the semiconductor manufacturing apparatus based on the predicted damage amount.

12. A semiconductor manufacturing apparatus comprising:

a chamber in which a wafer is disposed;

a sensor that detects an emission spectrum of light emitted in a visible wavelength region inside the chamber;

a calculation unit that;

obtains an equation for predicting emission intensity at each wavelength in an ultraviolet wavelength region that has been associated with an emission spectrum in a visible wavelength region, the equation having been calculated based on multivariable analysis;

predicts an emission spectrum in an ultraviolet wavelength region by using the equation and the detected emission spectrum,

predicts a damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region, and

calculates target process conditions inside the chamber based on the damage amount; and

wherein process conditions inside the chamber are set so as to meet the target process conditions that have been calculated by the calculation unit.

13. The semiconductor manufacturing apparatus according to claim 12,

wherein the calculation unit predicts a variation in a shape during a process by shape simulation after predicting the damage amount due to the ultraviolet rays and calculating the process conditions inside the chamber and calculates process conditions that are different from the previously calculated process conditions when the variation in the shape exceeds an acceptable range.

14. The semiconductor manufacturing apparatus according to claim 12,

wherein the calculation unit further detects a termination point of overetching after main etching when the predicted damage amount due to the ultraviolet rays reaches a preset damage amount.