INGAAS VERTICAL-CAVITY SURFACE-EMITTING LASERS

In this paper we give theoretical and experimental results for verticla-cavity surface-emitting lasers (VCSEL's). The modeling is applied to the design of InGaAs VCSEL's. A simple method is introduced to calculate the reflectivity of semiconductor stack mirrors with graded interfaces and compound metal/semiconductor stack mirrors. The theoretical predictions are compared to results from actual device measurements. A novel technique is introduced to determine material parameters: fabrication of in-plane lasers from VCSEL material. The procedure used to determine the optical mode in such an in-plane laser is described. Using the insight gained from our modeling, we have increased our external efficiency to > 30% with a threshold current density of 1 kA/cm2. Linewidth measurments on very high reflectivity VCSEL's have indicated widths as low as 85 MHz and linewidth-power products of 5 MHz. mW.