Height measurement device, exposure apparatus, and article manufacturing method

An exposure apparatus that projects a pattern of an original plate onto a substrate by using a projection optical system and exposes the substrate to light, the apparatus comprising:

• a positioning system including a substrate stage configured to hold the substrate;
• and
• a height measurement device configured to measure a height of the substrate held by the substrate stage,
• wherein the height measurement device comprises:
• an optical measurement device configured to measure a height of the substrate;
• an air sensor configured to measure a height of the substrate while discharging air through a pipeline based on a pressure in the pipeline;
• a member having a reference surface;
• and
• a controller configured to correct a result obtained by measuring a height at a second measurement location on the substrate using the optical measurement device based on a first result obtained by measuring a height at a first measurement location on the substrate and a height of the reference surface using the optical measurement device and a second result obtained by measuring a height at the first measurement location on the substrate and a height of the reference surface using the air sensor.

An article manufacturing method comprising:

• exposing a substrate to light by using an exposure apparatus;
• developing the substrate having undergone the exposing;
• and
• obtaining an article by processing the substrate having undergone the developing,
• wherein the exposure apparatus is configured to project a pattern of an original plate onto the substrate by using a projection optical system and exposes the substrate to light, the apparatus comprising:
• a positioning system including a substrate stage configured to hold the substrate;
• and
• a height measurement device configured to measure a height of the substrate held by the substrate stage,
• wherein the height measurement device comprises:
• an optical measurement device configured to measure a height of the substrate;
• an air sensor configured to measure a height of the substrate while discharging air through a pipeline based on a pressure in the pipeline;
• a member having a reference surface;
• and
• a controller configured to correct a result obtained by measuring a height at a second measurement location on the substrate using the optical measurement device based on a first result obtained by measuring a height at a first measurement location on the substrate and a height of the reference surface using the optical measurement device and a second result obtained by measuring a height at the first measurement location on the substrate and a height of the reference surface using the air sensor.