The present disclosure relates to an endpoint detection window of a polishing pad for use in a polishing process. The polishing pad may prevent an error in detection of the endpoint of the polishing process by preventing a difference in endpoint detection performance from occurring due to a difference in the wavelength of a laser between polishing apparatuses. The present disclosure may also provide a method of fabricating a semiconductor device using the polishing pad.

A processing end point detection method detects a timing of a processing end point (e.g., polishing stop, changing of polishing conditions) by calculating a characteristic value of a surface of a workpiece (an object of polishing) such as a substrate. This method includes producing a spectral waveform indicating a relationship between reflection intensities and wavelengths at a processing end point, with use of a reference workpiece or simulation calculation, based on the spectral waveform, selecting wavelengths of a local maximum value and a local minimum value of the reflection intensities, calculating the characteristic value with respect to a surface, to be processed, from reflection intensities at the selected wavelengths, setting a distinctive point of time variation of the characteristic value at a processing end point of the workpiece as the processing end point, and detecting the processing end point of the workpiece by detecting the distinctive point during processing of the workpiece.

A processing end point detection method detects a timing of a processing end point (e.g., polishing stop, changing of polishing conditions) by calculating a characteristic value of a surface of a workpiece (an object of polishing) such as a substrate. This method includes producing a spectral waveform indicating a relationship between reflection intensities and wavelengths at a processing end point, with use of a reference workpiece or simulation calculation, based on the spectral waveform, selecting wavelengths of a local maximum value and a local minimum value of the reflection intensities, calculating the characteristic value with respect to a surface, to be processed, from reflection intensities at the selected wavelengths, setting a distinctive point of time variation of the characteristic value at a processing end point of the workpiece as the processing end point, and detecting the processing end point of the workpiece by detecting the distinctive point during processing of the workpiece.

The disclosure provides a polishing apparatus capable of removing a polishing liquid or polishing debris from a light passing portion of a polishing pad. A polishing apparatus 1 includes a polishing table 3 supporting a polishing pad 2 that has a light passing portion 33; a polishing head 5 pressing a substrate W against a polishing surface 2a of the polishing pad 2; an optical sensor 21 disposed in the polishing table 3, irradiating light to the substrate W through the light passing portion 33, and receiving reflected light from the substrate W through the light passing portion 33; and a cleaning portion 12 forming a cleaning space CS that covers the light passing portion 33 above the light passing portion 33 and supplying a cleaning fluid to the light passing portion 33 through the cleaning space CS.

The disclosure provides a polishing apparatus capable of removing a polishing liquid or polishing debris from a light passing portion of a polishing pad. A polishing apparatus 1 includes a polishing table 3 supporting a polishing pad 2 that has a light passing portion 33; a polishing head 5 pressing a substrate W against a polishing surface 2a of the polishing pad 2; an optical sensor 21 disposed in the polishing table 3, irradiating light to the substrate W through the light passing portion 33, and receiving reflected light from the substrate W through the light passing portion 33; and a cleaning portion 12 forming a cleaning space CS that covers the light passing portion 33 above the light passing portion 33 and supplying a cleaning fluid to the light passing portion 33 through the cleaning space CS.

A method of polishing includes storing a predetermined location and a predetermined number as criteria for detecting an end point, polishing a substrate, measuring a sequence of current spectra of light reflected from the substrate while the substrate is being polished, identifying a plurality of peaks or valleys that persist with an evolving location through at least some of the sequence of current spectra, counting a number of peaks or valleys that were identified that pass the predetermined location as polishing progresses, and ceasing to polish the substrate when the number counted reaches the predetermined number.

A method of polishing includes storing a predetermined location and a predetermined number as criteria for detecting an end point, polishing a substrate, measuring a sequence of current spectra of light reflected from the substrate while the substrate is being polished, identifying a plurality of peaks or valleys that persist with an evolving location through at least some of the sequence of current spectra, counting a number of peaks or valleys that were identified that pass the predetermined location as polishing progresses, and ceasing to polish the substrate when the number counted reaches the predetermined number.

The present disclosure relates to an endpoint detection window of a polishing pad for use in a polishing process. The polishing pad may prevent an error in detection of the endpoint of the polishing process by preventing a difference in endpoint detection performance from occurring due to a difference in the wavelength of a laser between polishing apparatuses. The present disclosure may also provide a method of fabricating a semiconductor device using the polishing pad.

A polishing system receives one or more target parameters for a selected peak in a spectrum of light, polishes a substrate, measures a current spectrum of light reflected from the substrate while the substrate is being polished, identifies the selected peak in the current spectrum, measures one or more current parameters of the selected peak in the current spectrum, compares the current parameters of the selected peak to the target parameters, and ceases to polish the substrate when the current parameters and the target parameters have a pre defined relationship.

A polishing system receives one or more target parameters for a selected peak in a spectrum of light, polishes a substrate, measures a current spectrum of light reflected from the substrate while the substrate is being polished, identifies the selected peak in the current spectrum, measures one or more current parameters of the selected peak in the current spectrum, compares the current parameters of the selected peak to the target parameters, and ceases to polish the substrate when the current parameters and the target parameters have a pre defined relationship.