METAL-INSULATOR-METAL (MIM) CAPER WITH AN INSULATOR CUP AND A LATERALLY EXTENDING INSULATOR FLANGE

Abstract

A method comprising: forming a cup opening in a dielectric region (Vx); depositing a conformal metal layer over the dielectric region (Vx) and extending downward into the cup opening, wherein the deposited conformal metal forms (a) a cup-shaped conformal metal layer region in the cup opening and (b) a lateral conformal metal layer region extending laterally outward from a top surface of the cup-shaped conformal metal region;Removing a corner region of the conformal metal layer at a corner defined between the cup-shaped conformal metal layer region and the lateral conformal metal layer region, wherein a remaining portion of the cup-shaped conformal metal layer region defines a bottom electrode cup (136) comprising (a) a laterally extending bottom electrode cup base (140) and (b) a bottom electrode cup sidewall (142) extending upward from the laterally extending bottom electrode cup base (140); depositing an insulator layer comprising (a) an insulator cup (144) in an opening defined by the bottom electrode cup (136) and (b) an insulator flange (146) extending laterally outward from the insulator cup (144) and laterally over an upper surface of the bottom electrode cup sidewall (142);Deposition, above the insulator layer, of a top electrode layer extending into an opening defined by the insulator cup, wherein the top electrode layer includes a top electrode cap region (158) extending over the insulator flange (146), the insulator flange (146) being positioned between the top electrode cap region (158) and the upper surface of the bottom electrode cup sidewall (142); removal of upper portions of the top electrode layer, the insulator layer, and the conformal metal layer, wherein (a) a remaining portion of the top electrode layer defines a top electrode (122), and (b) a remaining portion of the insulator layer defines an insulator (124) comprising the insulator cup (144) and the insulator flange (146); and forming an electrode connection pad (160) for the top electrode (122) which is conductively connected to the top electrode (122);wherein the top electrode (122) is insulated from the upper surface of the bottom electrode cup sidewall (142) by the insulator flange (146); wherein the removal of the corner region of the conformal metal layer comprises: forming an oxide layer (224) having an opening over the corner region of the conformal metal layer, wherein part of the lateral conformal metal layer region remains covered by the oxide layer (224); and etching through the opening in the oxide layer (224) to remove the corner region of the conformal metal layer.

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