As today’s world is unthinkable without light emitting devices, questions of throughput, yield and tight control of the ever-increasing specifications become an increasingly important topic in semiconductor device production. Especially the first steps in the value chain – epitaxy and plasma etching – are both complex and crucial for the quality and yield of the final devices. In this presentation, we will discuss the capabilities of optical in-situ metrology for both the epitaxial and the plasma etch process. We will demonstrate that the precision of the in-situ control can be substantially increased when the metrology is connected across the different processes and measurement results are used to analyse downstream processes. Also for post-epitaxial 2D wafer mapping, that is used for characterizing wafer uniformity, the analysis capabilities are strongly extended, when layer thickness information of the whole layer stack are available from the in-situ metrology of the previous growth. In the talk we will show examples from different opto-electronical devices and highlight new developments in metrology.
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