Fig. 2: Figures showing common electronic packaging and assembly techniques.
From: Advances in waveguide to waveguide couplers for 3D integrated photonic packaging
In (a), the evolution from wirebonding (1D) to stacked die (3D) shows the increasing complexity of wiring within packages368. The plot in (b) shows the progression of bump technology over time (data up to 2020 is from ref. 369, with data after 2020 and future projections from refs. 30,370 which was in part derived from ref. 371), while (c) shows cross sections of the bumps used today, with both figures demonstrating current bumping pitches of <10 μm are possible370. The images in (d) show the common bonding processes used during assembly, which depends on the bumps technology used
