Method and apparatus for evaluating surface conditions of a sample

An apparatus for detecting residues on a sample by measuring intensity variations of a reflected probe beam resulting from periodic changes in optical reflectivity of the sample induced by localized periodic heating, said apparatus comprising:

• means for inducing a localized periodic heating at the surface of the sample;
• a probe for emitting a beam of radiation;
• means for directing the radiation probe beam within a portion of the area periodically heated by said periodic heating means in a manner such that the radiation probe beam reflects off the surface of the sample;
• means for measuring the intensity variations of the reflected radiation probe beam resulting from the periodic changes in optical reflectivity of the sample induced by the periodic heating with the measured intensity changes being independent of changes in diameter or position of the probe beam;
• and
• means for processing the measured intensity variations of the reflected radiation probe beam resulting from the periodic changes in optical reflectivity of the sample to determine if residues are present on the sample surface.

An apparatus for measuring dopant concentrations in a sample by measuring intensity variations of a reflected probe beam resulting from periodic changes in optical reflectivity of the sample induced by periodic heating, said apparatus comprising:

• means for inducing a localized periodic heating at the surface of the sample;
• a probe for emitting a beam of radiation;
• means for directing the radiation probe beam within a portion of the area periodically heated by said periodic heating means in a manner such that the radiation probe beam reflects off the surface of the sample;
• means for measuring the intensity variations of the reflected radiation probe beam resulting from the periodic changes in optical reflectivity of the sample induced by the periodic heating with the measured intensity changes being independent of changes in diameter or position of the probe beam;
• and
• means for processing the measured intensity variations of the reflected radiation probe beam resulting from the periodic changes in optical reflectivity of the sample to evaluate the dopant concentrations in the sample.

A method for evaluating the surface conditions on a sample by measuring intensity variations of a reflected probe beam resulting from the periodic changes in optical reflectivity of the sample induced by localized periodic heating, said method comprising the steps of:

• inducing a periodic localized heating on the surface of the sample;
• directing a radiation beam within a portion of the area periodically heated by the periodic heat source in a manner such that the radiation beam reflects from the surface of the sample;
• measuring the intensity variations of the reflected radiation beam resulting from said periodic changes in optical reflectivity of the sample induced by said periodic heating with the measured intensity changes being independent of changes in diameter or position of the probe beam;
• and
• processing the measured intensity variations of the reflected radiation beam resulting from the periodic changes in optical reflectivity of the sample to evaluate the conditions of the sample surface.

A method for detecting residues on a sample by measuring intensity variations of a reflected probe beam resulting from the periodic changes in optical reflectivity of the sample induced by localized periodic heating, said method comprising the steps of:

• inducing a periodic localized heating on the surface of the sample;
• directing a radiation beam within a portion of the area periodically heated by the periodic heat source in a manner such that the radiation beam reflects from the surface of the sample;
• measuring the intensity variations of the reflected radiation beam resulting from said periodic changes in optical reflectivity of the sample induced by said periodic heating with the measured intensity changes being independent of changes in diameter or position of the probe beam;
• and
• processing the measured intensity variations of the reflected radiation beam resulting from the periodic changes in optical reflectivity of the sample to determine if residues are present on the sample surface.

A method for measuring dopant concentrations in a sample by measuring intensity variations of a reflected probe beam resulting from the periodic changes in optical reflectivity of the sample induced by localized periodic heating, said method comprising the steps of:

• inducing a periodic localized heating on the surface of the sample;
• directing a radiation beam within a portion of the area periodically heated by the periodic heat source in a manner such that the radiation beam reflects from the surface of the sample;
• measuring the intensity variations of the reflected radiation beam resulting from said periodic changes in optical reflectivity of the sample induced by said periodic heating with the measured intensity changes being independent of changes in diameter or position of the probe beam;
• and
• processing the measured intensity variations of the reflected radiation beam resulting from the periodic changes in optical reflectivity of the sample to evaluate the dopant concentrations in the sample.