METHOD FOR FABRICATING SELF-ALIGNED FERROELECTRIC MEMORY TRANSISTOR

摘要

PURPOSE: A method for fabricating self-aligned ferroelectric memory transistor is provided to fabricate a ferroelectric stacked structure and its associated electrodes without contaminating a structure positioned under a self-aligned metal-ferroelectric-metal-oxide-semiconductor(MFMOS) memory transistor. CONSTITUTION: A substrate(10), a shallow trench isolation and polysilicon are prepared. A gate stack is formed. A silicon nitride layer is deposited. The silicon nitride layer, the bottom electrode and the polysilicon are selectively etched. The polysilicon is selectively etched to the level of the first dielectric layer. Ions are implanted and activated to form a source region and a drain region. A sidewall barrier layer is formed. A ferroelectric material layer is deposited. A top electrode structure is formed on the ferroelectric material. A passivation process, an oxide depositing process and a metallization process are performed.