Abstract: A method for recycling monitoring control wafers includes cleaning the wafers after performing a sheet resistance (Rs) measurement on a bare silicon monitoring control wafer of an ion implanter, and then converting the wafer into a recyclable control wafer. A recyclable control wafer for a thermal wave (TW) measurement of destruction can be obtained by forming a screen layer on the wafer, performing a TW measurement, performing ion implantation by the monitoring recipe, performing TW measurement again, performing ion drive-in to drive implanted ions into the deeper areas of the substrate, removing the screen layer, and then forming another screen layer on the wafer to put the wafer into the recycling process of a TW measurement.

Abstract: A method of in-line temperature monitoring. At least two control wafers and a monitor wafer are provided. A sacrificial layer is formed on each control wafer and the monitor wafer. Ions are implanted under a predetermined condition in the sacrificial layers. Thermal processes are performed on the control wafers at a higher and the lower limit of a target temperature to enable ions to move partially from the sacrificial layer to the control wafers. The sacrificial layers on the control wafers are subsequently removed. The sheet resistance of the control wafers is measured to obtain a first and the second resistance value, which respectively correspond to the first and second temperatures. A wafer and a monitor wafer are provided. A thermal process is performed on the monitor wafer and the wafer at the target temperature. The sacrificial layer of the monitor wafer is removed, and the sheet resistance of the monitor wafer is subsequently measured.