Polarized-cathodoluminescence study of stress for GaAs grown selectively on patterned Si(100) Academic Article uri icon

abstract

  • The spatial variation of stress tensor in selective‐area metalorganic chemical‐vapor‐ deposition‐grown GaAs on Si substrate by using a linearly polarized cathodoluminescence (CL) technique has been examined. The polarized CL technique enables a precise determination of the energy positions for the strain‐split j=3/2 valence‐band excitonic contributions to the luminescence by a simultaneous deconvolution of two CL spectra that are each taken under different polarization detection conditions; this procedure enables a mapping of the stress tensor. The biaxial in‐plane stress (σ∥=σ⊥; where ∥ and ⊥ denote parallel and perpendicular, respectively, to a 〈110〉‐oriented mesa edge) is found to decrease from ∼2.2 to 0.5 kbar as the square pattern size is decreased from 1 mm to 10 μm. Patterns having smaller dimension are found to have an increased luminescence efficiency, indicating a reduction in thermal stress induced dislocation density. The stress decay in the vicinity of edges and corners is found to be modeled...

publication date

  • January 1, 1994