METHOD FOR TERNARY WAFER BONDING AND STRUCTURE THEREOF

摘要

The present invention relates to a method for ternary wafer bonding and the structure thereof. According to the present invention, silver island structures in the second bonding layer are distributed on the first bonding layer deposited on the surface of a single silicon wafer for forming a gold-silver combination structure, which is then bonded with another silicon wafer without any metal layers thereon at a low-temperature thermal process of 250° C. for completing gold-silver-silicon ternary wafer bonding. Thus, the temperature required for gold-silicon bonding is lowered and the process of wafer bonding is simplified as well. In addition, the quality of wafer bonding is also assured.

主权项

1. A method for ternary wafer bonding, comprising steps of:
vapor depositing a first bonding layer on a first silicon wafer; disposing a second bonding layer on said first bonding layer, and said second bonding layer including a plurality of island structures distributed on said first bonding layer and exposing a portion of said first bonding layer; disposing a second silicon wafer on said second bonding layer; and performing thermal treatment for producing ternary bonding among said second silicon wafer, said first bonding layer, and said second bonding layer; wherein the material of said first bonding layer is gold and the material of said second bonding layer is silver.