Abstract

The electro-optical properties of semiconductors in the blue-green spectral region are of great interest because of their technological importance for optoelectronics, in particular modulators and bistable devices. We investigate the quantum confined Stark effect (QCSE) and Franz-Keldysh effect (FKE) in ZnCdSe/ZnSSe quantum-well and bulk-like structures at room temperature. For this purpose, differential transmission spectroscopy is performed on samples with different thickness of the active layers (4×5-, 10- , and 20 nm) to study the transition from QCSE to the FKE. The transition is expected for well widths below 15 nm due to the considerably smaller Bohr radius in the wide-band-gap H-VI semiconductors compared to conventional III-V semiconductors.

© 1998 IEEE