Semiconductor substrate measuring apparatus and plasma treatment apparatus using the same

A plasma treatment apparatus, comprising:

• a process chamber having an internal space to process a semiconductor substrate by generating plasma, the process chamber having an observation window through which plasma emission light emitted by the plasma is transmitted externally;
• a light source unit generating irradiation light including light in a first wavelength band and light in a second wavelength band, having a longer wavelength than the first wavelength band;
• an optical unit positioned above the observation window to irradiate the irradiation light to the semiconductor substrate through the observation window, and condensing reflected light, reflected from a surface of the semiconductor substrate and measurement light having the plasma emission light;
• a light splitting unit splitting the measurement light into a first optical path and a second optical path;
• a first detecting unit disposed on the first optical path and detecting first interference light in the first wavelength band in the measurement light;
• a second detecting unit disposed on the second optical path and detecting second interference light in the second wavelength band in the measurement light;
• and
• a controlling unit calculating at least one of a thickness or a surface shape of a membrane formed on the surface of the semiconductor substrate, based on the first interference light and calculating a temperature of the semiconductor substrate based on the second interference light.

A plasma treatment apparatus, comprising:

• a process chamber having an internal space to process a semiconductor substrate by generating plasma, the process chamber having an observation window;
• a light source unit disposed outside of the process chamber, generating irradiation light including light in a first wavelength band and a second wavelength band, having a longer wavelength than the first wavelength band;
• an optical unit positioned above the observation window to irradiate the irradiation light to the semiconductor substrate through the observation window;
• a light splitting unit splitting the reflected light to a first optical path and a second optical path;
• a first detecting unit disposed on the first optical path and detecting first interference light in the first wavelength band in the reflected light;
• a second detecting unit disposed on the second optical path and detecting second interference light in the second wavelength band in the reflected light;
• and
• a controlling unit calculating at least one of a thickness or a surface shape of a membrane formed on a surface of the semiconductor substrate, based on the first interference light and calculating a temperature of the semiconductor substrate based on the second interference light.