Apparatus for inspecting droplet and substrate processing apparatus including the same

An apparatus for inspecting a chemical solution comprising:

• a base unit having an inlet, through which a chemical solution is introduced;
• a flow path unit, in which the chemical solution introduced through the inlet is moved while a velocity of its fluid is changed, and including a first region unit provided adjacent to the inlet of the base unit and a second region unit being in series communication with the first region unit, in which the chemical solution discharged from the first region unit is moved;
• a detecting unit including a first detecting member for detecting a first signal that is an electrical signal of the first region unit, and a second detecting member for detecting a second signal that is an electrical signal of the second region unit;
• and
• a determining unit for receiving a signal from the detecting unit and determining that a particle and a bubble are detected if a current of the first signal and the second signal is changed compared to a reference value, and discriminating and determining a particle and a bubble according to a difference in a current between the first signal and the second signal or a time difference of current change durations detected by the first detecting member and the second detecting member,
• wherein the inlet is provided in a center of the base unit,
• wherein the flow path unit is provided radially from a center of the base unit,
• wherein the flow path unit includes a first section having a first width and a second section having a second width having a larger width compared to the first width,
• wherein each of the first section and the second section is provided at least one in each of the first region unit and the second region unit,
• wherein by receiving a rotational force from outside or generating a centrifugal force, a fluid velocity of the chemical solution moving in the second region unit is increased compared to the first region unit,
• wherein the detecting unit is electrically connected to the second section.