Position detecting system and processing apparatus
A position detecting system has a transport device, a light source, at least one optical element, a reflective member, a drive unit, and a controller. The transport device transports and places an object on a placement table. The light source generates measurement light. The optical element projects the measurement light, as projection light, generated by the light source and receives reflected light. The reflective member is disposed on the transport device. The reflective member reflects the projection light toward the placement table, and reflects the reflected light of the projection light, which is projected toward the placement table, toward the optical element. The drive unit operates the transport device so that the reflective member scans a plurality of linear scanning ranges. The controller calculates positional relationship between the focus ring and the object placed on the placement table based on the reflected light within the plurality of linear scanning ranges.
1. A position detecting system which is used in a processing apparatus having a placement table on which a disk-shaped object is placed and a focus ring which is disposed to surround a circumference of the object, the position detecting system comprising:
a transport device configured to transports the object and place the object on the placement table;
a light source configured to generate measurement light;
at least one optical element configured to project the measurement light, as projection light, generated by the light source and to receive reflected light;
a reflective member disposed on the transport device, and configured to reflect the projection light toward the placement table and reflect the reflected light of the projection light, which is projected toward the placement table, toward the optical element;
a drive unit configured to operate the transport device such that the reflective member scans a plurality of linear scanning ranges from the focus ring to the object placed on the placement table; and
a controller configured to calculate a positional relationship between the focus ring and the object placed on the placement table based on the reflected light within the plurality of linear scanning ranges.
2. The position detecting system according to claim 1 , wherein the controller is configured to determine whether or not the object is disposed at a target position on the placement table based on the positional relationship calculated for each of the scanning ranges.
3. The position detecting system according to claim 1 , wherein the transport device is configured to dispose the reflective member to correspond to the optical element.
4. The position detecting system according to claim 1 , wherein the processing apparatus has a chamber main body in which the placement table and the focus ring are disposed, and an upper electrode which is disposed above the focus ring, and the light source and the at least one optical element are disposed at a lateral side outside the chamber main body.
5. The position detecting system according to claim 1 , wherein among the plurality of linear scanning ranges, two scanning ranges are positioned on straight lines which are parallel to each other.
6. The position detecting system according to claim 1 , wherein among the plurality of linear scanning ranges, two scanning ranges are positioned on a single straight line.
7. The position detecting system according to claim 1 , wherein the controller calculates, for each of the scanning ranges, a difference between height information of the focus ring obtained based on the reflected light and reference height information of the focus ring obtained in advance.
8. A processing apparatus for processing a disk-shaped object, the processing apparatus comprising:
a placement table configured to place the object thereon;
a focus ring disposed to surround a circumference of the object; and
a position detecting system,
wherein the position detecting system includes:
a transport device configured to transport the object and place the object on the placement table;
a light source configured to generate measurement light;
at least one optical element configured to projects the measurement light, as projection light, generated by the light source and receives reflected light;
a reflective member disposed on the transport device, and configured to reflect the projection light toward the placement table and reflect the reflected light of the projection light, which is projected toward the placement table, toward the optical element;
a drive unit configured to move the transport device such that a plurality of linear scanning ranges from the focus ring to the object placed on the placement table are scanned to the reflective member; and
a controller configured to calculate a positional relationship between the focus ring and the object placed on the placement table based on the reflected light within the plurality of linear scanning ranges.