I. Introduction
Photonic module manufacturers pursue stable, precise, long-term, miniature module realization and assembly technologies in order to achieve cost-effective and reliable solutions for market demands. The integration of photonic, electrical, and mechanical functionalities into one system can greatly improve the cost efficiency of systems, due the fact that the packaging cost is reduced [1], [2]. In addition, the very tight alignment tolerance requirements between discrete single mode photonic devices are mainly avoided through high precision lithographic or comparable processing technologies, which further enhances the long-term performance and reliability of the systems [3], [4]. The monolithic integration of data processing and photonics devices in a single chip, however, is not yet feasible at least economically and hybrid integration is still applicable [5]. In our previous paper, we introduced a passive alignment of devices using low-temperature cofired ceramics (LTCC) substrates utilizing alignment structures in cost-effective hybrid integration of photonic modules [6]. The manufacturing cost per produced module can be evaluated using the cost-of-ownership (COO) model, in which the investments in processing and manufacturing machines, production floor, accessories and work costs are summed up [7]. The possibility to evaluate the module concepts and optimize detailed structures and tolerances through simulations is a cost-effective approach to photonic module integration. The realization and characterization of the prototype devices and modules verifies the module design and offers information to enhance design and simulation models.