High quality electrical contacts between integrated circuit chips

摘要

Methods and structures of connecting at least two integrated circuits in a 3D arrangement by a zigzag conductive chain are disclosed. The zigzag conductive chain, acting as a spring or self-adaptive contact structure (SACS) in a wafer bonding process, is designed to reduce bonding interface stress, to increase bonding interface reliability, and to have an adjustable height to close or eliminate undesirable opens or voids between two integrated circuits.

主权项

1. A multi-layer structure, comprising:
(a) a first wafer including a plurality of landing pads; (b) a second wafer; (c) a first interconnect attached to the surface of the second wafer comprising a zigzag conductive chain interposed between the first wafer and the second wafer, the zigzag conductive chain including a via at its top, said via forming a bonding relation with a first landing pad of the first wafer, and; (d) a second interconnect attached to the surface of the second wafer, not disposed on a zigzag conductive chain, the second interconnect having a top surface, wherein the zigzag conductive chain is downward bent when the bonding relation is formed between the via and the first wafer, and wherein the top surface of the second interconnect is in contact with the first wafer when a bonding relation is formed between the second interconnect and the first wafer.