In-situ monitoring of substrate surfaces

In some examples, a vacuum pre-processing module (VPM) metrology system is provided for measuring sheet resistance of a layer on a substrate. The system may include an eddy current sensor including a transmitter sensor and a receiver sensor, the transmitter sensor and the receiver sensor defining a gap between the transmitter sensor and the receiver sensor, the gap for receiving an edge of a substrate to be tested. A sensor controller receives a measurement signal from the eddy current sensor. A data processor processes the measurement signal and generates a sheet resistance value for the layer on the substrate. 在一些示例中，提供了一种真空预处理模块(VPM)计量系统，其用于测量衬底上的层的薄层电阻。所述系统可以包含：涡流传感器，所述涡流传感器包括发送器传感器与接收器传感器，所述发送器传感器与所述接收器传感器限定所述发送器传感器与所述接收器传感器之间的间隙，所述间隙用于容纳待测试的衬底的边缘。传感器控制器从所述涡流传感器接收测量信号。数据处理器处理所述测量信号并且产生所述衬底上的所述层的薄层电阻值。