Application of chemical‐mechanical polishing for planarizing of silicon nitride passivation layers used in high power III‐V laser devices

Abstract

AbstractChemical‐mechanical polishing (CMP) allows the planarization of wafers with thin layer at its surface. Subject of this investigation was to apply CMP for planarizing silicon nitride (Si3N4) passivation layer in high power III‐V laser devices, which remained in the structure as the insulation and planarization layer. For planarizing a nitride layer, oxide CMP slurry was used in conjunction with standard CMP polishing pads. Since III‐V materials, such as GaAs and InP, are very soft and fragile, the CMP process must be well controlled to avoid the ridge crack. The optimum CMP conditions have been presented in the paper, which gave the desirable surface quality. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)