Mechanical strain mapping of GaAs based VCSELs

Merwan Mokhtari (1) , Philippe Pagnod-Rossiaux (2) , Christophe Levallois (3) , Francois Laruelle (2) , Daniel T Cassidy (4) , Mauro Bettiati (2) , Jean-Pierre Landesman (3)

1 IPR - Institut de Physique de Rennes
2 3SP Technologies
3 FOTON - Institut des Fonctions Optiques pour les Technologies de l'informatiON
4 McMaster University [Hamilton, Ontario]

We report an investigation of the strain field in mesa structures for oxide-confined vertical-cavity surface-emitting lasers (VCSELs) using the polarization-resolved micro-photoluminescence (PL) measurement of the degree of polarization (DOP) at room temperature. The DOP of the PL is correlated with the spatial distribution of the embedded anisotropic strain in a VCSEL structure. Measurements normal to (100) surfaces of the samples and from (110) cross-sectional planes were performed. The effect of two processes required in the fabrication of GaAs-based VCSELs was studied: the plasma etching of the P-doped distributed Bragg reflector and the wet oxidation process used to control current flow and lateral optical confinement. The DOP method allows very sensitive measurements of the mechanical strain (on the order of 10 - 5) accumulated in VCSEL devices even during different steps of the fabrication process.

Domaines: Physique [physics]

Merwan Mokhtari, Philippe Pagnod-Rossiaux, Christophe Levallois, Francois Laruelle, Daniel T Cassidy, et al.. Mechanical strain mapping of GaAs based VCSELs. Applied Physics Letters, 2021, 118 (9), pp.091102. ⟨10.1063/5.0040386⟩. ⟨hal-03190309⟩