SIMULATION METHOD, SIMULATION PROGRAM, AND SEMICONDUCTOR MANUFACTURING APPARATUS

• US 20130133832A1
• Filed: 11/13/2012
• Published: 05/30/2013
• 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
• Granted Patent: US 9,287,097 B2
• Time in Patent Office: Days
• US Class Current: 156/345.25
• 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 simulation method for predicting a damage amount due to ultraviolet rays in manufacturing a semiconductor device, the method comprising:

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 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; and

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

2. The simulation 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 simulation 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 simulation program for predicting a damage amount due to ultraviolet rays in manufacturing a semiconductor device, the program causing an information processing apparatus to mount thereon and execute functions of:

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 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; and

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

5. A semiconductor manufacturing apparatus comprising:

a chamber in which a wafer is disposed;

a sensor which detects an emission spectrum in a visible wavelength region inside the chamber;

a calculation unit which calculates particle density by performing simulation based on a differential equation for the particle density, calculates emission intensity at each wavelength in a 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 an emission spectrum in the visible wavelength region, which has been actually detected with the sensor, 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 process conditions inside the chamber so as to minimize the damage amount; and

a control unit which controls process conditions inside the chamber so as to meet the process conditions which 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 process conditions inside the chamber and calculates process conditions which are different from the previously calculated process conditions when the variation in the shape exceeds an acceptable 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 simulation method for predicting a damage amount due to ultraviolet rays in manufacturing a semiconductor device, the method comprising:

calculating an equation for predicting emission intensity at each wavelength in an ultraviolet wavelength region, which has been associated with an emission spectrum in a visible wavelength region, based on multivariable analysis;

predicting an emission spectrum in the ultraviolet wavelength region n by using the calculated predicting equation and an actually detected emission spectrum in the visible wavelength region; and

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

9. The simulation 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 simulation 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 simulation program for predicting a damage amount due to ultraviolet rays in manufacturing a semiconductor device, the program causing an information processing apparatus to mount thereon and execute functions of:

calculating an equation for predicting emission intensity at each wavelength in an ultraviolet wavelength region, which has been associated with an emission spectrum in a visible wavelength region, based on multivariable analysis;

predicting an emission spectrum in the ultraviolet wavelength region by using the calculated predicting equation and an actually detected emission spectrum in the visible wavelength region; and

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

12. A semiconductor manufacturing apparatus comprising:

a chamber in which a wafer is disposed;

a sensor which detects an emission spectrum in a visible wavelength region inside the chamber;

a calculation unit which predicts an emission spectrum in the ultraviolet wavelength region by using an equation for predicting emission intensity at each wavelength in the ultraviolet wavelength region, which has been calculated based on multivariable analysis in association with an emission spectrum in a visible wavelength region, and an emission spectrum in the visible wavelength region, which has been actually detected with the sensor, predicts a damage amount due to the ultraviolet rays based on the predicted emission spectrum in the ultraviolet wavelength region, and calculates process conditions inside the chamber so as to minimize the damage amount; and

a control unit which controls process conditions inside the chamber so as to meet the process conditions which 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 which 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.