M. Weyers

Ferdinand-Braun-Institute, Jenoptik Diod Lab, LayTec AG

  • 10A.3 – Efficient Front-End Manufacturing of High-Quality VCSEL – Enabled by In-Situ and Ex-Situ Optical Metrology During Epi Growth and Processing

    A. MaaBdorf, Ferdinand-Braun-Institute, Jenoptik Diod Lab, LayTec AG
    J.-T Zettler, LayTec AG
    M. Brendel, Ferdinand-Braun-Institut (FBH)
    A. Renkewitz, Ferdinand-Braun-Institut (FBH)
    Ralph-Stephan Unger, Ferdinand-Braun-Institut (FBH)
    K. Haberland, LayTec AG
    M. Weyers, Ferdinand-Braun-Institute, Jenoptik Diod Lab, LayTec AG

    10A.3 Final.2025

    Abstract
    VCSEL layer structures are among the most complicated ones in compound semiconductor device production. Re-establishing growth conditions for a new epi campaign after chamber maintenance can be challenging and time consuming. This work is about how to tackle this challenge by applying in-situ optical metrology during growth and processing of GaAs-based VCSEL devices as well as post-growth ex-situ wafer mapping. We demonstrate how to efficiently combine in-situ and ex-situ white light reflectance (WLR) measurements and modelling in order to increase the target wavelength accuracy.
    Fitting the in-situ reflectance transient or the ex-situ WLR is used to generate a target reflectance trace for the subsequent plasma etching of the VCSEL mesa enabling automated end pointing.