Abstract

Passive alignment is a key technology for low-cost packaging of single-mode fiber-coupled devices for telecommunication applications. The method is even more advantageous for packaging arrays, because all of the fiber ports axe coupled in one simple operation. Several examples of coupling a laser to a fiber held in a V-groove on a silicon substrate have been published.¹"³ In this paper, we report coupling from a laser array mounted directly on a silica-on-silicon passive waveguide array, as shown in Fig. 1. Using this scheme, an active laser array can be coupled to a passive silica-on-silicon circuit such as a filter or a combiner. This type of functionality is very desirable for devices such as WDM transmitters. We present a technique that can achieve excellent coupling while preserving the thermal performance of p-down mounted laser diodes. To this effect, we use micromachined alignment features on both the diode laser and the silicon carrier, combined with a thin-solder process compatible with conventional p-down laser bonding techniques.

© 1996 Optical Society of America