Wafer inspecting apparatus

A wafer inspecting apparatus for obliquely irradiating a wafer with rays and detecting rays which are scattered from the wafer, and are caused by foreign matter adhering to the surface of the wafer and by internal defects in the wafer comprising:

• a first scattered ray detecting system for detecting scattered rays from the wafer;
• and
• a second scattered ray detecting system for detecting scattered rays from the wafer;
• wherein said irradiation rays are composed of two kinds of rays having two wavelengths which are selected such that the penetration depth in the wafer of said rays having one wavelength is three times or more larger or smaller than that of rays having the other wavelength;
• wherein with respect to at least one kind of said two rays having said two wavelengths,
• said first scattered ray detecting system is disposed in a first direction where he intensity of scattered rays which are scattered from a foreign matter adhering on the surface of the wafer and detected by said first scattered ray inspecting system is larger than the intensity of scattered rays which are scattered from the foreign matter and detected by said second scattered ray inspecting system, and the intensity of scattered rays which are scattered from an internal defect of the wafer and detected by said first scattered ray inspecting system is smaller than the intensity of scattered rays which are scattered from the internal defect and detected by said second scattered ray inspecting system,
• said second scattered ray inspecting system is disposed in a second direction where the intensity of scattered rays which are scattered from a foreign matter adhering on the surface of the wafer and detected by said second scattered ray inspecting system is smaller than the intensity of scattered rays which are scattered from the foreign matter and detected by said first scattered ray inspecting system, and the intensity of scattered rays which are scattered from an internal defect of the wafer and detected by said second scattered ray inspecting system is larger than the intensity of scattered rays which are scattered from the internal defect and detected by said first scattered ray inspecting system;
• and;
• a comparator comparing the intensity of the scattered rays detected by said first scattered ray inspecting system with the intensity of the scattered rays detected by said second scattered ray inspecting system to distinguish the foreign matter and the internal defects from each other.

A wafer inspecting apparatus for obliquely irradiating a wafer with rays and detecting rays which are scattered from the wafer, and are caused by foreign matter adhering to the surface of the wafer and by internal defects in the wafer comprising:

• a first scattered ray detecting system for detecting scattered rays from the wafer;
• and
• a second scattered ray detecting system for detecting scattered rays from the wafer;
• wherein said irradiation rays are composed of two kinds of rays having two wavelengths which are selected such that the penetration depth in the wafer of said rays having one wavelength is three times or more larger or smaller than that of rays having the other wavelength;
• wherein with respect to at least one kind of said two rays having said two wavelengths,
• said first scattered ray inspecting system detects scattered rays which are scattered from the wafer at an angle of the reflection angle of said irradiation rays or more, and
• said second scattered ray inspecting system detects scattered rays which are scattered from the wafer at an angle less than the reflection angle of said irradiation rays;
• and;
• a comparator comparing the intensity of the scattered rays detected by said first scattered ray inspecting system with the intensity of the scattered rays detected by said second scattered ray inspecting system to distinguish the foreign matter and the internal defects from each other.

A wafer inspecting apparatus for obliquely irradiating a wafer with rays and detecting rays which are scattered from the wafer, and are caused by foreign matter adhering to the surface of the wafer and by internal defects in the wafer comprising:

• a first scattered ray inspecting system for detecting scattered rays which are scattered from the wafer at an angle of the Brewster angle or more;
• a second scattered ray inspecting system for detecting scattered rays which are scattered from the wafer at an angle less than the Brewster angle;
• and;
• a comparator comparing the intensity of the scattered rays detected by said first scattered ray inspecting system with the intensity of the scattered rays detected by said second scattered ray inspecting system to distinguish the foreign matter and the internal defects from each other.

A wafer inspecting apparatus for obliquely irradiating a wafer with rays and detecting rays which are scattered from the wafer, and are caused by foreign matter adhering to the surface of the wafer and by internal defects in the wafer comprising:

• a first scattered ray inspecting system for detecting scattered rays from the wafer;
• wherein said irradiation rays are composed of two kinds of rays having two wavelengths which are selected such that the penetration depth in the wafer of said rays having one wavelength is three times or more larger or smaller than that of said rays having the other wavelength;
• and
• wherein with respect to at least one kind of said two rays having said two wavelengths,
• said first scattered ray inspecting system detects scattered rays which are scattered from the wafer at an angle of the Brewster angle or more, and
• said second scattered ray inspecting system detects scattered rays which are scattered from the wafer at an angle less than the Brewster angle;
• and;
• a comparator comparing the intensity of the scattered rays detected by said first scattered ray inspecting system with the intensity of the scattered rays detected by said second scattered ray inspecting system to distinguish the foreign matter and the internal defects from each other.

A wafer inspecting apparatus for obliquely irradiating a wafer with rays and detecting rays which are scattered from the wafer, and are caused by foreign matter adhering to the surface of the wafer and by internal defects in the wafer comprising:

• a first scattered ray inspecting system for detecting scattered rays from the wafer;
• and
• a second scattered ray inspecting system for detecting scattered rays from the wafer;
• wherein said irradiation rays are composed of two kinds of rays having first and second wavelengths which are selected such that the penetration depth in the wafer of said rays having said first wavelength is three times or more larger or smaller than that of said rays having said second wavelength and said first scattered ray inspecting system is adapted to detect the scattered rays having said first wavelength and scattered from the wafer and said second scattered ray inspecting system is adapted to detect the scattered rays having said second wavelength and scattered from the wafer;
• wherein said first scattered ray detecting system is disposed in a first direction where the intensity of scattered rays which are scattered from a foreign matter adhering on the surface of the wafer and detected by said first scattered ray inspecting system is larger than the intensity of scattered rays which are scattered from the foreign matter and detected by said second scattered ray inspecting system, and the intensity of scattered rays which are scattered from an internal defect of the wafer and detected by said first scattered ray inspecting system is smaller than the intensity of scattered rays which are scattered from the internal defect and detected by said second scattered ray inspecting system,
• said second scattered ray inspecting system is disposed in a second direction where the intensity of scattered rays which are scattered from a foreign matter adhering on the surface of the wafer and detected by said second scattered ray inspecting system is smaller than the intensity of scattered rays which are scattered from the foreign matter and detected by said first scattered ray inspecting system, and the intensity of scattered rays which are scattered from an internal defect of the wafer and detected by said second scattered ray inspecting system is larger than the intensity of scattered rays which are scattered from the internal defect and detected by said first scattered ray inspecting system;
• and;
• a comparator comparing the intensity of the scattered rays detected by said first scattered ray inspecting system with the intensity of the scattered rays detected by said second scattered ray inspecting system to distinguish the foreign matter and the internal defects from each other.

A wafer inspecting apparatus for obliquely irradiating a wafer with rays and detecting rays which are scattered from the wafer, and are caused by foreign matter adhering to the surface of the wafer and by internal defects in the wafer comprising:

• a first scattered ray inspecting system for detecting scattered rays from the wafer;
• and
• a second scattered ray inspecting system for detecting scattered rays from the wafer;
• wherein said irradiation rays are composed of two kinds of rays having first and second wavelengths which are selected such that the penetration depth in the wafer of said rays having said first wavelength is three times or more larger or smaller than that of said rays having said second wavelength;
• wherein said first scattered ray inspecting system detects the scattered rays having said first wavelength and scattered from the wafer at an angle of the reflection angle of said irradiation rays or more, and said second scattered ray inspecting system detects the scattered rays having said second wavelength and scattered from the wafer at an angle of less than the reflection angle of said irradiation rays;
• and;
• a comparator comparing the intensity of the scattered rays detected by said first scattered ray inspecting system with the intensity of the scattered rays detected by said second scattered ray inspecting system to distinguish the foreign matter and the internal defects from each other.

A wafer inspecting apparatus for obliquely irradiating a wafer with rays and detecting rays which are scattered from the wafer, and are caused by foreign matter adhering to the surface of the wafer and by internal defects in the wafer comprising:

• a first scattered ray inspecting system for detecting scattered rays from the wafer;
• and
• a second scattered ray inspecting system for detecting scattered rays from the wafer;
• wherein said irradiation rays are composed of two kinds of rays having first and second wavelengths which are selected such that the penetration depth in the wafer of said rays having said first wavelength is three times or more larger or smaller than that of said rays having said second wavelength;
• wherein said first scattered ray inspecting system detects the scattered rays having said first wavelength and scattered from the wafer at an angle of the Brewster angle or more, and said second scattered ray inspecting system detects the scattered rays having said second wavelength and scattered from the wafer at an angle of less than the Brewster angle;
• and;
• a comparator comparing the intensity of the scattered rays detected by said first scattered ray inspecting system with the intensity of the scattered rays detected by said second scattered ray inspecting system to distinguish the foreign matter and the internal defects from each other.