We report the mass production of blue LEDs on dry-etched patterned sapphire substrates using the AIX R6 tool in a 31×4" configuration. The system was operated in a continuous run mode, i.e. cleaning the showerhead after a series of LED runs. Production stability was characterized by monitoring of wavelength, light output power (LOP), and electrostatic discharge (ESD) yields. We developed a dynamic multi-zone Topside Temperature Control and the TEQualizer function. The TEQualizer function is based on a 400nm pyrometry open loop wafer surface temperature control, using Inside P400 by Laytec. Combining this wafer-to-wafer and run -to-run temperature stability improvement with an optimized wafer carrier, we demonstrated an on-wafer uniformity of stdv of 1.1nm, a wafer-to-wafer uniformity of stdv 1.1nm and a run-to-run reproducibility of stdv <1nm, resulting in a total wafer area wavelength yield of >90% in a 6 nm bin. LOP stability was demonstrated within a 3% window with no visible run-to-run trend. An absolute buffer layer growth temperature window was defined through a Design of Experiment on buffer layers targeting best ESD yield - in particular looking into defect related morphology and its correlation with Inside P400 readings. We have demonstrated an ESD yield >90% in continuous run mode to be used in the mass production of InGaN based blue LEDs.
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