interesting new job opening at Inphi. What are those "interposer technologies "

Inphi is headquartered out of Singapore  

Bit of a reach on my part.I'm hungry for news    

https://jobs.jobvite.com/inphi-corporation/job/oUtwdfwQ

Responsibilities:
The Staff Engineer will be responsible to drive development of innovative packaging technologies for Inphi’s advanced 2.5D/3D devices with applications in optical networking systems. The successful candidate will work in collaboration with external wafer foundries to develop back-end processes and with OSAT sites to develop assembly processes for advanced CMOS nodes and silicon photonics devices, stacked die assemblies, interposer technologies and other emerging packaging technologies for highly integrated multi-chip module products with silicon and III-V compound semiconductors. The Staff Engineer will be responsible for defining package design rules and assembly rules to meet manufacturability and yield requirements. Work in a cross-functional team to ensure developed processes maintain high yield in a HVM environment, including quality and reliability industry standards for data center applications.