Multiple-wavelength vertical-cavity surface-emitting laser arrays

Multiple-wavelength vertical-cavity surface-emitting InGaAs QW laser (MW-VCSEL) arrays are fabricated using two patterned-substrate growth techniques both in conjunction with a location-resolvable in situ laser reflectometer in a molecular beam epitaxy (MBE) system. A backside pattern on the substrate is used to induce a temperature profile on the growth surface. In the first technique, we used a temperature-dependent growth rate to create MW-VCSEL´s, whereas for the second, uniform growth was first performed followed by a temperature-dependent redesorption process to create the thickness gradient required for MW-VCSEL´s. We achieved a record wavelength span, accurate and repeatable lasing wavelengths, and reproducible multiple-wavelength VCSEL arrays with high performance. Comparison between the two methods will be discussed