Photonic integrated circuits (PIC) combine many optical functionalities on the surface of a chip, fabricated using the same technologies as used for microelectronics. PICs have become a major enabler for optical communication, first in long-haul fiber-optic telecom systems, and more recently in datacenter links. But even with this crucial role in our current internet infrastructure, PIC technology is still in its early days, comparable to electronics in the late 1980s or early 1990s. To become really impactful, Photonic chips need to scale in multiple aspects, and the emerging trends today are paving the way for this scaling. First of all, we need to enable more complex photonic circuit architectures, and support their design, fabrication, packaging and control. The overall performance of the on-chip building blocks also needs to improve, and this often requires new materials, just like the introduction of copper interconnects, high-k dielectrics and strained silicon boosted electronics. Photonics also needs to break out of its narrow market of optical communication: new demonstrations in sensing, spectrometry, diagnostics, LiDAR and quantum processing will scale the addressable market, and thus the production volumes needed to bring down the cost. But extending to other markets also pushes demand for even more variety in materials, as different applications require the use of different optical wavelengths.