Novel concepts for III-N-based vertical cavity surface emitting lasers

Vertical cavity surface emitting lasers in the visible wavelength region are interesting for projection and display purposes as well as for scientific applications. Although VCSELs in the blue wavelength region were already demonstrated, they are not yet commercially available. We discuss different concepts and demonstrate highly conductive epitaxially grown AlInN/GaN Bragg mirrors which can promote better current spreading and enable short cavity VCSEL design. Such layers with degenerative germanium doped GaN layers achieve Ohmic behavior with low specific resistivities of 5×10 -4 Ωcm 2 and high reflectivities above 99 % for 45-fold DBRs.