MULTIWAVELENGTH INGAAS/INGAASP STRAINED-LAYER MQW-LASER ARRAY USING SHADOW-MASKED GROWTH

In this letter we present a simple technique for the fabrication of multiwavelength laser arrays. The lateral variations in bandgap (or emission wavelength) between the different lasers are obtained by the use of shadow masked growth. The shadow masked growth results in variations in thickness (and to a lesser extent, in composition) over the substrate. In combination with a multiquantum well (MQW) active region, this gives the required bandgap variations. By varying the window width in the shadow mask between 10-mu-m and >500-mu-m it was possible to obtain a wavelength span of 130 nm centered around 1.55-mu-m. The strained-layer-ridge MQW Fabry-Perot lasers showed a constant threshold current (around 70 mA for a 11-mu-m x 500-mu-m stripe).