METHOD AND DEVICE FOR MEASURING DEFECT OF CRYSTAL ON CRYSTAL SURFACE

• Main Authors: WATASE, SHINICHIRO, HIRAIWA, ATSUSHI, ISHIDA, HIDETSUGU, TAKEDA, KAZUO, TAJIMA, TAKESHI
• Format: Patent
• Language: English; French; Japanese
• Published: 25.09.1997
• Edition: 6
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

In a measuring method by which internal defects of a crystal are detected using scattered light, it is made possible to measure the size, depth from the surface and position of each internal defect of the sample with a resolution shorter than the wavelength of the scattered light. The sample is scanned with two light beams which have different wavelengths penetrating the sample to different depths, one being more than three times as large as the other, the intensity of scattered light by an internal defect for either wavelength is measured, the size of the defect is found from the intensity of the scattered light of the longer wavelength, and the depth and position of the defect are found from the ratio of the intensity of the scattered light of the long wavelength to that of the other wavelength. The found depth, position, and size of the defect are displayed in the form of in-plane distribution of a wafer. According to the wide-area surface measurement a camera is moved to the position of a specific defect of the defects detected, the defect is observed by scanning the sample with the two light beams having different wavelengths and the depth, position, and size of the defect are found similarly from the picture data obtained from the scattered light of two wavelengths. By the method of this invention, the sizes, depths, and positions of the defects can be measured by examining the entire surface of the sample and by observing the image of the defect one by one.