Abstract : This work deals with the fabrication and the characterization of buried oxide-confined vertical-cavity surface-emitting lasers for optical communications and microsystems. The introduction presents a review on current research topics on materials as well as VCSEL integration in microsystems. Several ways to associate the photodetection function in the vertical structure of a VCSEL are then detailed. We first focus on the realization of single mode sources laser at 850 nm for these applications. Vertical structure design and process are detailed. We expose our technological choices for the fabrication of the devices, especially on the realization of the oxide aperture, and present the experimental set-up used for the characterizations. Optical and electrical measurements show the improvements of the VCSELs characteristics and allows for identify current limitations. Further, we explain the principle of resonant cavity enhanced detector and then describe each detailed vertical geometry: single photodetector, VCSEL and BiVCSEL. Measured spectral behaviors on each device are shown and discussed. Lateral detection is then theoretically and experimentally studied. The physical principle involved in this original study is the optical waveguiding of spontaneous emission between neighboring VCSELs sharing the same cavity. Results of our electrical and optical measurements are exhibited. The main application of this new detection system concerns the VCSEL power monitoring. Finally, we conclude on the results obtained and on further improvements of this work.