SEMICONDUCTOR FABRICATING APPARATUS WITH FUNCTION OF DETERMINING ETCHING PROCESSING STATE

• US 20080020495A1
• Filed: 08/17/2007
• Published: 01/24/2008
• Est. Priority Date: 03/04/2003
• Status: Active Grant

• Current Assignee: Kazuhiro Jyouo, Motohiko Yoshigai, Tatehito Usui, Tetsuo Ono
• Original Assignee: Kazuhiro Jyouo, Motohiko Yoshigai, Tatehito Usui, Tetsuo Ono
• Inventors: Usui, Tatehito, Jyouo, Kazuhiro, Yoshigai, Motohiko, Ono, Tetsuo
• Granted Patent: US 8,071,397 B2
• Time in Patent Office: Days
• US Class Current: 438/9
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/67253 Process monitoring, e.g. flow or thickness monitoring

Abstract

A semiconductor fabricating method including: placing the semiconductor wafer having a film thereon inside of a chamber; generating plasma; detecting a quantity of interference lights for each of at least two wavelengths obtained from a surface of the wafer for a predetermined time period during the etching of the wafer; detecting a first time point at which the detected quantity of interference lights for one of the two wavelengths becomes a maximum and a second time point at which the detected quantity of interference lights for the other wavelength becomes a minimum; determining a state of etching based on a result of comparing a predetermined value with an interval between the first and second time points, wherein both time points are detected by using outputs of a detector for detecting a quantity of the interference lights; and controlling etching in accordance with the determining.

Claims

1. (canceled)

2. A semiconductor fabricating apparatus for etching a semiconductor wafer, which is disposed within a chamber and has a lower layer film and a film to be processed disposed above the lower layer film, by using plasma generated within the chamber, comprising:

a detector which detects an amount relating to interference light of a plurality of different wavelengths as to each of the wavelengths during a predetermined time period for processing the film to be processed, the interference light being obtained from a surface of the wafer; and

a determination unit which detects a change of the amount relating to the interference light according to a progress of the etching process obtained during the predetermined time period from the detector by using the plurality of different wavelengths of the interference light as a parameter, and determines a thickness of the lower layer film based on a waveform as to which the amount changes by a predetermined value or more.

3. A semiconductor fabricating apparatus according to claim 2, wherein the determination unit determines the thickness of the lower layer film based on the waveforms representing peak values of the detected amounts between which a wavelength changes by a predetermined wavelength value or more according to a progress of the etching process.

4. A semiconductor fabricating apparatus according to claim 2, wherein the determination unit determines the thickness of the lower layer film based on the waveforms representing peak values of the detected amounts between which a changing direction of the peak values is reversed according to a progress of the etching process.

5. A semiconductor fabricating apparatus for etching a semiconductor wafer which is disposed within a chamber and has a lower layer film and a film to be processed disposed above the lower layer film, by using plasma generated within the chamber, comprising:

a detector which detects an amount relating to interference light of a plurality of different wavelengths as to each of the wavelengths, during a predetermined time period for processing the film to be processed, the interference light being obtained from a surface of the wafer;

a determination unit which detects a change of the amount relating to the interference light according to a progress of the etching process obtained during the predetermined time period from the detector by using the plurality of different wavelengths of the interference light as a parameter, and determines a thickness of the lower layer film based on the waveform as to which the amount changes by a predetermined value or more; and

a notification unit which notifies a result of the determination of the determination unit.

6. A semiconductor fabricating apparatus according to claim 5, wherein the determination unit determines the thickness of the lower layer film based on the waveforms representing peak values of the detected amounts between which a wavelength changes by a predetermined wavelength value or more according to a progress of the etching process.

7. A semiconductor fabricating apparatus according to claim 5, wherein the determination unit determines the thickness of the lower layer film based on the waveforms representing peak values of the detected amounts between which a changing direction of the peak values is reversed according to a progress of the etching process.

8. A method of fabricating a semiconductor in which a semiconductor wafer having a lower layer film and a film to be processed disposed above the lower layer film is disposed within a chamber and the film to be processed is etched by using plasma generated within the chamber, the method comprising:

detecting an amount relating to interference light of a plurality of different wavelengths as to each of the wavelengths, during a predetermined time period for processing the film to be processed, the interference light being obtained from a surface of the wafer;

detecting a change of the amount relating to the interference light according to a progress of the etching process obtained during the predetermined time period from the detector by using the plurality of different wavelengths of the interference light as a parameter; and

determining a thickness of the lower layer film based on the waveform as to which the amount changes by a predetermined value or more.

9. A method of fabricating a semiconductor according to claim 8, wherein

the determining operation includes a sub-operation of determining the thickness of the lower layer film based on the waveforms representing peak values of the detected amounts between which a wavelength changes by a predetermined wavelength value or more according to a progress of the etching process.

10. A method of fabricating a semiconductor according to claim 8, comprising:

notifying a result of the determination of the thickness of the lower layer film.