Temperature measuring method and apparatus, measuring method for the thickness of the formed film, measuring apparatus for the thickness of the formed film thermometer for wafers

• US 6,541,287 B2
• Filed: 03/03/1999
• Issued: 04/01/2003
• Est. Priority Date: 03/19/1998
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Soga, Akira, Ino, Tomomi, Akama, Yoshiaki
• Primary Examiner(s): Niebling, John F.
• Assistant Examiner(s): Stevenson, André C
• Application Number:
  US09/261,972
• Publication Number:
  US 20020066859A1
• Time in Patent Office: 1,490 Days
• Field of Search: 374/130, 216/60, 250/559.29, 438/14, 438/16
• US Class Current: 438/16
• CPC Class Codes: G01J 5/0003 for sensing the radiant heat transfer of samples, e.g. emittance meter

Abstract

A temperature measuring apparatus, comprises a light splitting section for splitting the light radiated from a substrate into plural light components having wavelengths over a predetermined wavelength region, a detection section for detecting the intensities of the light components obtained by the light splitting section, an integrated value calculating section for calculating an integrated value of radiation intensity by cumulatively adding the intensities of the light components detected by the detecting section, and a surface temperature calculating section for calculating the surface temperature of the substrate from the integrated value, on the basis of reference data representing the relation between the temperature and the integrated value.

Claims

1. A film thickness measuring method for measuring a thickness of an uppermost film being formed on a substrate, said method comprising:

a step of actually measuring an intensity distribution of light radiated from said substrate;

a step of calculating a relative intensity distribution of the radiated light, which is a ratio of the actually measured intensity distribution of the radiated light to a reference intensity distribution obtained for the radiated light on the basis of the light radiated from the substrate before initiation of the film formation; and

a step of calculating the thickness of the film by comparing a theoretical intensity distribution of the radiated light, derived from transmitted light theory, with said relative intensity distribution of the radiated light.

2. The method according to claim 1, wherein said comparison between the theoretical intensity distribution and the relative intensity distribution is performed by waveform matching.

3. The method according to claim 1, wherein said comparison between the theoretical intensity distribution and the relative intensity distribution is performed on the basis of a maximum wavelength shift which the relative intensity distribution has with respect to the theoretical intensity distribution.

4. A film thickness measuring method for measuring a thickness of an uppermost film being formed on a substrate, said method comprising:

a step of measuring a first split light intensity distribution on the basis of light radiated from the substrate and light reflected from the substrate illuminated with light which has a broadband spectrum distribution before initiation of the film formation;

a step of measuring a second split light intensity distribution on the basis of light radiated from the substrate before initiation of the film formation, said substrate having ceased to be illuminated with light;

a step of measuring a third split light intensity distribution on the basis of light radiated from the substrate and light reflected from the substrate during the film formation, said substrate being illuminated with light having a broadband spectrum distribution;

a step of measuring a fourth split light distribution based on the light radiated from the substrate during the film formation, said substrate having ceased to be illuminated with light;

a first arithmetic step for obtaining a reference intensity distribution of only the reflected light on the basis of said first split light intensity distribution and said second split light intensity distribution;

a second arithmetic step for obtaining an actually measured intensity distribution of only the reflected light on the basis of said third split light intensity distribution and said fourth split light intensity distribution;

a step of calculating a relative intensity distribution of the reflected light for obtaining a relative intensity distribution of the reflected light, which is a ratio of the actually measured intensity distribution of the reflected light to said reference intensity distribution obtained for the reflected light; and

a step of calculating a thickness of the film by comparing said relative intensity distribution of the reflected light with a reference intensity distribution of the reflected light having a known relation with the thickness of the film.

5. A film thickness monitoring method comprising the steps of:

illuminating a pattern formed on a wafer with a laser beam;

receiving a diffracted light reflected from the pattern by using a sensor; and

measuring a thickness of a thin film on the wafer based on an intensity of the diffracted light.

6. A wafer temperature thickness monitoring method for monitoring a temperature of a wafer on which a predetermined pattern is formed, said method comprising the steps of:

illuminating said pattern with a laser beam;

receiving a diffracted light reflected from the pattern by using a sensor via a lens;

calculating the temperature of the wafer based on a position of a spot image formed on the sensor; and

measuring a thickness of a thin film on the wafer based on an intensity of the diffracted light, wherein said lens is arranged between the sensor and the pattern such that a distance between the sensor and the lens is equal to a focal length of the lens.

7. A film thickness measuring method for measuring a thickness of an uppermost film when a working process is applied to a substrate having an underlying film formed thereon, said method comprising:

a step of measuring intensity of a split light radiated or reflected from a reference sample of said substrate before formation of an underlying film on said substrate;

a step of measuring intensity of split light radiated or reflected from a measured sample of said substrate after formation of an underlying film on the substrate;

a step of measuring intensity of a split light radiated or reflected during the film formation process on the substrate;

a step of calculating a thickness of the underlying film on the basis of a peak position obtained by dividing the intensity of the split light radiated or reflected from said measured sample, by the intensity of the split light radiated or reflected from said reference sample; and

a step of calculating thickness of the uppermost film on the basis of a peak position obtained by dividing the intensity of the split light radiated or reflected during the film formation process, by the intensity of the split light radiated or reflected form the measured sample, wherein a relationship between the peak position for every thickness of the underlying film and the thickness of the uppermost film is calculated in said step of calculating the thickness of the uppermost film, said peak position having been stored in advance based on the thickness of the underlying film obtained in said step of calculating the thickness of the underlying film.

8. A method for performing a process on a substrate on which an underlying film is formed, said method comprising the steps of:

measuring an intensity of a split light radiated or reflected from said substrate;

storing a database created based on an intensity of a split light radiated or reflected from a reference sample of said substrate before the formation of the underlying film on said substrate or a database created based on an intensity of a split light radiated or reflected from the measured sample of the substrate after the formation of the underlying on the substrate;

calculating a thickness of the uppermost film based on the intensity of the split light radiated or reflected from the substrate under the process of the basis of said database; and

controlling said process to be ceased when the thickness of the uppermost film reaches a predetermined value.