Patent ID: 9673186
Date: 2017-06-06
CPC Classifications: H01L

Claim:
1. A method for fabricating a compound semiconductor integrated circuit, sequentially comprising steps of: growing at least one compound semiconductor epitaxial layer on a substrate of a first chip; fabricating at least one compound semiconductor electronic device on the substrate using the at least one compound semiconductor epitaxial layer; depositing at least one second metal layer made essentially of Au above the at least one compound semiconductor epitaxial layer to form an electrical connection to at least one of the at least one compound semiconductor electronic device, and also to form at least one second pad; depositing a SiN layer above the at least one second metal layer for passivation or protection of the at least one compound semiconductor electronic device, and hereafter, the layer comprising the at least one compound semiconductor electronic device, the at least one second metal layer, and the SiN layer defined as an electronic device layer; depositing a dielectric layer above the electronic device layer; forming at least one dielectric layer via hole penetrating through the dielectric layer for the electrical contact to the at least one second pad; depositing a first metal layer made essentially of Cu on the dielectric layer forming at least one first pad on the dielectric layer, extending from the each first pad into the at least one dielectric layer via hole and connecting to the at least one second pad, where the first metal layer extends from at least one of the at least one first pad three-dimensionally over at least one of the at least one compound semiconductor device, then into the at least one dielectric layer via hole and connects to the at least one second pad; and stacking a second chip containing an electronic circuit over the first metal layer and electrically connecting to at least one of the at least one first pad to connect the electronic circuit in the second chip to the semiconductor integrated circuit in the first chip.