Apparatus and method of manufacturing a semiconductor device
In order to reduce the occurrence of current alarms in a semiconductor etching or deposition process, a controller determines an offset in relative positions of a cover ring and a shield over a wafer within a vacuum chamber. The controller provides a position alarm and/or adjusts the position of the cover ring or shield when the offset is greater than a predetermined value or outside a range of acceptable values.
1. A method, comprising:
disposing a workpiece on a support stage in a chamber;
disposing a shield over the workpiece;
disposing a cover ring over the shield such that an opening in the shield is aligned with an opening in the cover ring in order to expose the support stage;
determining a first radial offset of the shield with respect to the support stage and a second radial offset of the cover ring with respect to the support stage;
adjusting a relative position of the shield and the cover ring when an absolute value of a difference between the first radial offset of the shield and the second radial offset of the cover ring is determined greater than an offset threshold value of 0.3 millimeters (mm); and
wherein the chamber further comprises a position sensor and a position adjustment mechanism for:
determining the first radial offset of the shield with respect to the support stage and the second radial offset of the cover ring with respect to the support stage using the position sensor;
comparing the absolute value of the difference to the offset threshold value, wherein the offset threshold value is stored in an electronic memory;
instructing the position adjustment mechanism to adjust the relative position of the shield and the cover ring when the absolute value of the difference is determined greater than the offset threshold value; and
commencing a semiconductor manufacturing process on the workpiece when the absolute value of the difference is determined less than the offset threshold value.
2. The method of claim 1 , wherein the comparing and the instructing are performed iteratively until the absolute value of the difference is determined less than the offset threshold value.
3. The method of claim 1 , wherein the semiconductor manufacturing process is at least one of an etching operation and a physical vapor deposition operation.
4. A method, comprising:
disposing a workpiece over a support stage in a processing chamber;
determining a first radial offset of a shield with respect to the support stage and a second radial offset of a cover ring with respect to the support stage, wherein the shield is disposed over the support stage and the cover ring is disposed over the shield;
determining whether an absolute value of a difference between the first radial offset of the shield and the second radial offset of the cover ring is within a tolerance range of between 0 and 0.3 millimeters (mm);
adjusting a relative position of at least one of the shield and the cover ring when the offset the absolute value of the difference is not within the tolerance range; and
wherein the processing chamber further comprises a position sensor and a position adjustment mechanism for:
determining the first radial offset of the shield with respect to the support stage and the second radial offset of the cover ring with respect to the support stage using the position sensor;
comparing the absolute value of the difference to the tolerance range, wherein the tolerance range is stored in an electronic memory;
instructing the position adjustment mechanism to adjust the relative position of the at least one of the shield and the cover ring when the absolute value of the difference is determined greater than the tolerance range; and
performing a semiconductor device processing operation on the workpiece after confirming that the absolute value of the difference is within the tolerance range.
5. The method of claim 4 , wherein the semiconductor device processing operation is at least one of: etching the workpiece disposed on the support stage and depositing a material on the workpiece disposed on the support stage.
6. The method of claim 5 , wherein the depositing a material is a physical vapor deposition operation.
7. The method of claim 1 , wherein the position sensor is configured to determine whether the shield and the cover ring are aligned by measuring a distance between an outer periphery of the shield and an edge of the second opening.
8. The method of claim 1 , further comprising re-aligning the shield and the cover ring based on the difference between the first radial offset and the second radial offset determined by the position sensor.
9. The method of claim 1 , further comprising adjusting the relative position of the cover ring with respect to the wafer support stage.
10. The method claim 1 , further comprising:
comparing the absolute value of the difference to the offset threshold value; and
generating an alarm when the absolute value of the difference is determined greater than the offset threshold value.
11. The method of claim 1 , further comprising placing a deposition ring between the cover ring and the shield within the chamber.
12. The method of claim 11 , wherein the position sensor is configured to further determine whether the deposition ring and at least one of the shield and the cover ring are aligned such that the absolute value of the difference is less than the offset threshold value.