Thermal Analysis of Reflow Process for PIC-Embedded Package Substrate with 2.3D RDL Interposer for Co-Packaged Optics

Toward a next generation co-packaged optics (CPO), we have worked on a novel package substrate in which photonics integrated circuits (PICs) are embedded. The substrate can be provided as known good package substrate with optoelectronic conversion function and can be assembled in the same condition as conventional package substrates. In addition, the substrate realizes high-density optical assembly by optical redistribution layer (RDL). In this paper, we show design of the test vehicle using 2.3D electrical RDL interposer and provide its thermal analysis results for a reflow process.