Patent ID: 7662649

Claim:
A method of assessing alignment of semiconductor wafer substrate within a deposition apparatus, comprising: providing a deposition apparatus having a substrate susceptor for receiving a semiconductor wafer substrate, having one or more laser emitters configured to reflect laser light from the substrate, and having one or more photodetectors configured to detect the reflected laser light; providing a semiconductor wafer substrate received by the susceptor; emitting light from at least one of the laser emitters toward the substrate such that at least some of the light reflects from the substrate to at least one of the photodetectors; detecting the emitted light with said at least one of the photodetectors; utilizing information about the detected light to assess alignment of the substrate; using the information about the detected light to make susceptor adjustments to improve the alignment; wherein the utilization of the information and improving of alignment comprises making susceptor adjustments until an approximately maximum signal is received by the photodetector; and wherein two or more of the laser emitters are utilized together with two or more of the photodetectors, wherein each of the laser emitters is paired with one of the photodetectors, and wherein the utilization of the information and improving of alignment comprises making susceptor adjustments until approximately maximum signals are received by all of the photodetectors.