Optical sensors for measuring properties of consumable parts in a semiconductor plasma processing chamber

A method of manufacturing semiconductor devices, comprising:

• repeatedly performing a transfer operation which transfers each of a plurality of semiconductor wafers between a wafer handling module and a processing chamber through a wafer access port, the processing chamber comprising at least one consumable component;
• performing, using the processing chamber, a semiconductor manufacturing process on each of the plurality of semiconductor wafers;
• and
• detecting an optical signal from the at least one consumable component during a time when the processing chamber is not performing the semiconductor manufacturing process on the wafers, wherein the detecting the optical signal includes
• acquiring a diffuse light image and a structured light image of one of the at least one consumable component,
• using the diffuse light image to detect edges of the one of the at least one consumable component,
• using the structured light image to identify intersecting points where structured light intersects the edges detected from the diffuse light image, and
• constructing a three-dimensional profile of the one of the at least one consumable component based on the intersecting points.