发明名称 |
Polishing method and polishing apparatus |
摘要 |
A method of polishing a substrate is disclosed. The method includes irradiating the substrate with light; measuring intensity of the reflected light; producing spectral waveform representing relationship between relative reflectance and wavelength of the light; performing a Fourier transform process on the spectral waveform to determine a thickness of the film and a corresponding strength of frequency component; determining whether the determined thickness of the film is reliable or not by comparing the strength of frequency component with a threshold value; calculating a defective data rate representing a proportion of the number of unreliable measured values to the total number of measured values; and changing the threshold value based on the defective data rate. |
申请公布号 |
US9266214(B2) |
申请公布日期 |
2016.02.23 |
申请号 |
US201414260229 |
申请日期 |
2014.04.23 |
申请人 |
Ebara Corporation |
发明人 |
Kimba Toshifumi |
分类号 |
B24B37/00;B24B37/013;B24B49/12;H01L21/306 |
主分类号 |
B24B37/00 |
代理机构 |
Baker & Hostetler LLP |
代理人 |
Baker & Hostetler LLP |
主权项 |
1. A method of polishing a substrate having a film, the method comprising:
polishing the substrate by pressing the substrate against a polishing tool on a rotating polishing table; irradiating the substrate with light when polishing the substrate; receiving the light reflected from the substrate; measuring intensity of the reflected light at respective wavelengths; calculating relative reflectance by dividing the measured intensity of the light by predetermined reference intensity; producing spectral waveform representing relationship between the relative reflectance and wavelength of the light; performing a Fourier transform process on the spectral waveform to determine a thickness of the film and a corresponding strength of frequency component; determining that the determined thickness of the film is a reliable measured value if the strength of frequency component is higher than a predetermined threshold value; determining that the determined thickness of the film is an unreliable measured value if the strength of frequency component is equal to or lower than the predetermined threshold value; determining a polishing end point of the substrate based on a point of time when the reliable measured value has reached a predetermined target value; calculating a defective data rate representing a proportion of the number of unreliable measured values to the total number of reliable measured values and unreliable measured values that have been obtained previously; and changing the predetermined threshold value based on the defective data rate. |
地址 |
Tokyo JP |