In some embodiments, the weight meter 210 is configured to measure a weight difference between a first measurement and a second measurement. In some embodiments, the first measurement is performed before the deposition process. In some embodiments, the second measurement is performed after the deposition process. Therefore, in some embodiments, the weight difference measured by the weight meter 210 indicates the weight of the material deposited on the wafer W during the deposition process.

Although FIG. 2 does not show any material disposed on the wafer W, it is obvious to one of skill in the art that the wafer W has materials and/or structures disposed thereon after the deposition process.

In some embodiments, the process driver 220 is configured to control the process of the measuring device 200. Accordingly, the process driver 220 is configured to send a signal to the data collection control unit 230 to trigger the operation of the weight meter 210.

In some embodiments, the processor 240 is configured to receive the data from the weight meter 210 and further configured to analyze the data. In some embodiments, the processor 240 is configured to communicate with process driver 220, the data collection control unit 230, the weight meter 210, or the combination thereof.