Study on no IMC Solid state bonding method for high-density 2.5D/3D integration

Abstract Chiplet integration is a new development direction for the continuation and even goes beyond Moore’s Law, and in order to achieve the high density, high reliability, high-speed Chiplet device, a new method of 2.5D/3D integration approach is needed to fulfill the needs to Chiplet heterogeneous devices. In this work, two dies were successfully bonded via low energy input with no IMC solid state bonding under 220°C and 5 MPa, which is much gentler than the other solid state bonding approaches. Each die had a matrix of 22500 Cu pillars with a diameter of 20 μm. This method was promising for the near future high-density 2.5D/3D integration.