EFFECTS OF LAYER THICKNESS VARIATIONS ON VERTICAL-CAVITY SURFACE-EMITTING DBR SEMICONDUCTOR-LASERS

We present a theoretical analysis of the influence of layer thickness variation in vertical-cavity surface-emitting lasers with distributed Bragg reflectors (DBR) on lasing wavelength. We show that changing the active region length or one of the layers in the DBR mirror by only one unit cell (0.56 nm) is sufficient to produce shifts in the lasing wavelength up to 0.12 nm (for an AIGaAs laser). This could limit the precision with which we can obtain a desired wavelength, its reproducibility, and its uniformity across a large wafer. We also discuss possible influences on the linewidth of broad area devices. © 1990 IEEE