METHOD OF FABRICATING SELF-ALIGNED EXTERNAL CONTACTS IN CMOS AND BiCMOS PROCESSES USING CHEMICAL MECHANICAL POLISHING CMP

摘要

A method of forming external contacts in an integrated circuit structure using chemical mechanical polishing (CMP) techniques is disclosed. The integrated circuit structure includes an active substrate region defined by field oxide. A substrate surface region is defined between the first and second diffusion regions formed in the active region. According to the present invention, after a layer of amorphous or polycrystalline silicon is formed in contact with the diffusion region, a chemical mechanical polishing (CMP) step is performed and then etched to form an external contact. The process flow can be applied to bipolar as well as CMOS technology to provide BiCMOS flow.