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US 6,444,558 B1Granted
Methods of forming and programming junctionless antifuses
AssigneeMicron Technology, Inc.
InventorsDouglas J. Cutter, Fan Ho, Kurt D. Beigel
Life of this patent
Estimating the term…
Abstract
A method and apparatus for forming a junctionless antifuse semiconductor structure comprises forming an antifuse in non-active areas of a semiconductor wafer. In one embodiment, the antifuse is formed over a polysilicon layer, which is coupled to a field oxide layer. In a further embodiment, the polysilicon layer comprises a bottom conductor layer in the antifuse. In another embodiment, a refractory metal silicide layer is formed between the polysilicon layer and the antifuse. In yet a further embodiment, the refractory metal silicide layer comprises the bottom conductor layer in the antifuse.
Claims45
A method for selectively forming an antifuse in an integrated circuit, comprising:
- forming a first conductive island of the antifuse and a second conductive island of the antifuse on an insulator, wherein the insulator is supported by a semiconductor substrate and insulates the first conductive island and the second conductive island from the semiconductor substrate;
- forming a refractory metal silicide layer on the first and second conductive islands;
- forming a bottom conductor layer on the refractory metal silicide layer of the first conductive island;
- forming a programming layer on the bottom conductor layer;
- and
- forming a top conductor layer on the programming layer, wherein the top conductor layer overlies at least a portion of the second conductive island,
- wherein the refractory metal silicide layer on the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the bottom conductor layer of the antifuse through the first conductive island and the refractory metal silicide layer on the first conductive island, and
- wherein the refractory metal silicide layer on the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the top conductor layer of the antifuse.
5 more elements
A method for selectively forming an antifuse in an integrated circuit, comprising:
- forming a first conductive island of the antifuse and a second conductive island of the antifuse on an insulator, wherein the first conductive island comprises a bottom conductor layer and the insulator is supported by a semiconductor substrate and insulates the first conductive island and the second conductive island from the semiconductor substrate;
- forming a programming layer on the bottom conductor layer;
- and
- forming a top conductor layer on the programming layer, wherein the top conductor layer overlies at least a portion of the second conductive island,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the bottom conductor layer of the antifuse, and
- wherein the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the top conductor layer of the antifuse.
3 more elements
A method of programming an integrated circuit antifuse from a first state to a second state, comprising:
- applying a voltage through a first contact to a first conductor layer in the first state, wherein the first conductor layer is formed over a non-active device region of a semiconductor substrate and is insulated from the semiconductor substrate, further wherein the first conductor layer is coupled to a programming layer, the programming layer is coupled to a second conductor layer, and the second conductor layer is coupled to a second contact that is formed over and extends to a conductive island of the antifuse that is formed over the non-active device region of the semiconductor substrate, that is insulated from the semiconductor substrate, and that functions as an etch stop for the second contact coupled to the second conductor layer, still further wherein the first conductor layer is electrically isolated from the second conductor layer by the programming layer in the first state;
- and
- forming a conductive path through the programming layer in response to the voltage, wherein the conductive path electrically couples the first conductor layer to the second conductor layer, further wherein the anti fuse assumes the second state when the first conductor layer is electrically coupled to the second conductor layer.
A method of forming an integrated circuit antifuse, comprising:
- forming a first conductor layer that comprises a first conductive island of the antifuse and a second conductive island of the antifuse, wherein the first conductor layer is formed over a non-active device region of a semiconductor substrate, wherein the first conductor layer is insulated from the semiconductor substrate;
- forming a second conductor layer overlying at least a portion of the second conductive island;
- and
- forming a programming layer interposed between the first conductive island and the second conductor layer,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the first conductor layer of the antifuse, and
- wherein the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the second conductor layer of the antifuse.
3 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conductor layer over a non-active device region of a semiconductor substrate, wherein the first conductor layer is insulated from the semiconductor substrate, wherein the first conductor layer comprises a first conductive island of the antifuse and a second conductive island of the antifuse;
- forming a second conductor layer overlying at least a portion of the second conductive island;
- and
- forming a programming layer, wherein the programming layer is interposed between the first conductor layer and the second conductor layer, further wherein the programming layer comprises at least one layer of electrically-insulative programming layer material,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the bottom conductor layer of the antifuse, and
- wherein the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the top conductor layer of the antifuse.
3 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conductor layer over a non-active device region of a semiconductor substrate, wherein the first conductor layer is insulated from the semiconductor substrate, wherein the first conductor layer comprises a first conductive island of the antifuse and a second conductive island of the antifuse;
- forming a second conductor layer overlying at least a portion of the second conductive island;
- and
- forming a programming layer, wherein the programming layer is interposed between the first conductor layer and the second conductor layer, further wherein the programming layer comprises at least one layer of electrically-insulative programming layer material and at least one layer of diffusion barrier material,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the first conductor layer of the antifuse, and
- wherein the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the second conductor layer of the antifuse.
3 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conductor layer over a non-active device region of a semiconductor substrate, wherein the first conductor layer is insulated from the semiconductor substrate, wherein the first conductor layer comprises a first conductive island of the antifuse and a second conductive island of the antifuse;
- forming a bottom conductor layer coupled to the first conductive island;
- forming a programming layer coupled to the bottom conductor layer, wherein the programming layer comprises at least one layer of electrically-insulative programming layer material;
- and
- forming top conductor layer coupled to the programming layer, wherein the top conductor layer overlies at least a portion of the second conductive island,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the bottom conductor layer of the antifuse through the first conductive island, and
- wherein the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the top conductor layer of the antifuse.
4 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conducting layer over a non-active device region of a semiconductor substrate, wherein the first conducting layer is insulated from the semiconductor substrate, wherein the first conducting layer comprises a first conductive island of the antifuse and a second conductive island of the antifuse;
- forming a bottom conductor layer coupled to the first conductive island;
- forming a programming layer coupled to the bottom conductor layer, wherein the programming layer comprises at least one layer of electrically-insulative programming layer material and at least one layer of diffusion barrier material;
- and
- forming top conductor layer coupled to the programming layer, wherein the top conductor layer overlies at least a portion of the second conductive island,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the bottom conductor layer of the antifuse through the first conductive island, and
- wherein the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the top conductor layer of the antifuse.
4 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conducting layer over a non-active device region of a semiconductor substrate;
- forming a second conducting layer coupled to the first conducting layer, wherein the first conducting layer and the second conducting layer:comprise a first conductive island of the antifuse and a second conductive island of the antifuse, wherein the first conductive island and the second conductive island are insulated from the semiconductor substrate;
- forming a bottom conductor layer coupled to the second conducting layer on the first conductive island;
- forming a programming layer coupled to the bottom conductor layer, wherein the programming layer comprises at least one layer of electrically-insulative programming layer material;
- and
- forming top conductor layer coupled to the programming layer, wherein the top conductor layer overlies at least a portion of the second conductive island,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the bottom conductor layer of the antifuse through the first conducting layer and the second conducting layer of the first conductive island, and
- wherein the second conducting layer on the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the top conductor layer of the antifuse.
5 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conducting layer over a non-active device region of a semiconductor substrate;
- forming a second conducting layer coupled to the first conducting layer, wherein the first conducting layer and the second conducting layer comprise a first conductive island of the antifuse and a second conductive island of the antifuse, wherein the first conductive island and the second conductive island are insulated from the semiconductor substrate;
- forming a bottom conductor layer coupled to the second conducting layer on the first conductive island;
- forming a programming layer coupled to the bottom conductor layer, wherein the programming layer comprises at least one layer of electrically-insulative programming layer material and at least one layer of diffusion barrier material;
- and
- forming top conductor layer coupled to the programming layer, wherein the top conductor layer overlies at least a portion of the second conductive island,
- wherein the first conductive island of the antifuse is adapted to function as an etch stop for a first electrical contact to the bottom conductor layer of the antifuse, and
- wherein the second conductive island of the antifuse is adapted to function as an etch stop for a second electrical contact to the top conductor layer of the antifuse.
5 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conducting layer over a field oxide region of a semiconductor substrate;
- forming a second conducting layer over the first conducting layer;
- removing a portion of the first conducting layer and the second conducting layer to form a first conductive island, a second conductive island and an exposed portion of the field oxide region;
- forming a first layer of insulating material over the first conductive island, the second conductive island and the exposed portion of the field oxide region;
- removing a portion of the first layer of insulating material, wherein removing a portion of the first layer of insulating material produces a recess defined by a surface of the first layer of insulating material, an exposed surface of the first conductive island and at least one wall of insulating material interposed between the surface of the first layer of insulating material and the exposed surface of the first conductive island;
- forming a layer of electrically-insulative programming layer material over the surface of the first layer of insulating material, the at least one wall of insulating material and the exposed surface of the first conductive island;
- forming a third conducting layer over the layer of electrically-insulative programming layer material;
- removing a portion of the layer of electrically-insulative programming layer material to produce a programming layer;
- removing a portion of the third conducting layer to produce a top conductor layer, wherein removing a portion of the layer of electrically-insulative programming layer material and removing a portion of the third conducting layer further produces a second exposed portion of the first layer of insulating material and an exposed portion of the layer of electrically-insulative programming layer material;
- forming a second layer of insulating material over the second exposed portion of the layer of insulating material, the exposed portion of the layer of electrically-insulative programming layer material and the top conductor layer;
- forming a first contact through the second layer of insulating material and the first layer of insulating material to the first conductive island, wherein the first contact is electrically coupled to the second conducting layer of the first conductive island;
- and
- forming a second contact through the second layer of insulating material, the top conductor layer and the first layer of insulating material to the second conductive island, wherein the second contact is electrically coupled to the top conductor layer.
10 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conducting layer over a field oxide region of a semiconductor substrate;
- removing a portion of the first conducting layer to form a first conductive island, a second conductive island and an exposed portion of the field oxide region;
- forming a first layer of insulating material over the first conductive island, the second conductive island and the exposed portion of the field oxide region;
- removing a portion of the first layer of insulating material, wherein removing a portion of the first layer of insulating material produces a recess defined by a surface of the first layer of insulating material, an exposed surface of the first conductive island and at least one wall of insulating material interposed between the surface of the first layer of insulating material and the exposed surface of the first conductive island;
- forming a layer of electrically-insulative programming layer material over the surface of the first layer of insulating material, the at least one wall of insulating material and the exposed surface of the first conductive island;
- forming a second conducting layer over the layer of electrically-insulative programming layer material;
- removing a portion of the layer of electrically-insulative programming layer material to produce a programming layer;
- removing a portion of the second conducting layer to produce a top conductor layer, wherein removing a portion of the layer of electrically-insulative programming layer material and removing a portion of the second conducting layer further produces a second exposed portion of the first layer of insulating material and an exposed portion of the layer of electrically-insulative programming layer material;
- forming a second layer of insulating material over the second exposed portion of the layer of insulating material, the exposed portion of the layer of electrically-insulative programming layer material and the top conductor layer;
- forming a first contact through the second layer of insulating material and the first layer of insulating material to the first conductive island, wherein the first contact is electrically coupled to the first conducting layer of the first conductive island;
- and
- forming a second contact through the second layer of insulating material, the top conductor layer and the first layer of insulating material to the second conductive island, wherein the second contact is electrically coupled to the top conductor layer.
9 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conducting layer over a field oxide region of a semiconductor substrate;
- removing a portion of the first conducting layer to form a first conductive island, a second conductive island and an exposed portion of the field oxide region;
- forming a first layer of insulating material over the first conductive island, the second conductive island and the exposed portion of the field oxide region;
- removing a portion of the first layer of insulating material, wherein removing a portion of the first layer of insulating material produces a recess defined by a surface of the first layer of insulating material, an exposed surface of the first conductive island and at least one wall of insulating material interposed between the surface of the first layer of insulating material and the exposed surface of the first conductive island;
- forming a second conducting layer over the surface of the first layer of insulating material, the at least one wall of insulating material and the exposed surface of the first conductive island;
- removing a portion of the second conducting layer to produce a bottom conductor layer and a first exposed portion of the first layer of insulating material;
- forming a layer of electrically-insulative programming layer material over the bottom conductor layer and the first exposed portion of the first layer of insulating material;
- forming a third conducting layer over the layer of electrically-insulative programming layer material;
- removing a portion of the layer of electrically-insulative programming layer material to produce a programming layer;
- removing a portion of the third conducting layer to produce a top conductor layer, wherein removing a portion of the layer of electrically-insulative programming layer material and removing a portion of the third conducting layer further produces a second exposed portion of the first layer of insulating material and an exposed portion of the layer of electrically-insulative programming layer material;
- forming a second layer of insulating material over the second exposed portion of the layer of insulating material, the exposed portion of the layer of electrically-insulative programming layer material and the top conductor layer;
- forming a first contact through the second layer of insulating material and the first layer of insulating material to the first conductive island, wherein the first contact is electrically coupled to the first conducting layer of the first conductive island;
- and
- forming a second contact through the second layer of insulating material, the top conductor layer and the first layer of insulating material to the second conductive island, wherein the second contact is electrically coupled to the top conductor layer.
11 more elements
A method of forming an integrated circuit antifuse, comprising:
- forming a first conducting layer over a field oxide region of a semiconductor substrate;
- forming a second conducting layer over the first conducting layer;
- removing a portion of the first conducting layer and the second conducting layer to form a first conductive island, a second conductive island and an exposed portion of the field oxide region;
- forming a first layer of insulating material over the first conductive island, the second conductive island and the exposed portion of the field oxide region;
- removing a portion of the first layer of insulating material, wherein removing a portion of the first layer of insulating material produces a recess defined by a surface of the first layer of insulating material, an exposed surface of the first conductive island and at least one wall of insulating material interposed between the surface of the first layer of insulating material and the exposed surface of the first conductive island;
- forming a third conducting layer over the surface of the first layer of insulating material, the at least one wall of insulating material and the exposed surface of the first conductive island;
- removing a portion of the third conducting layer to produce a bottom conductor layer and a first exposed portion of the first layer of insulating material;
- forming a layer of electrically-insulative programming layer material over the bottom conductor layer and the first exposed portion of the first layer of insulating material;
- forming a fourth conducting layer over the layer of electrically-insulative programming layer material;
- removing a portion of the layer of electrically-insulative programming layer material to produce a programming layer;
- removing a portion of the fourth conducting layer to produce a top conductor layer, wherein removing a portion of the layer of electrically-insulative programming layer material and removing a portion of the fourth conducting layer further produces a second exposed portion of the first layer of insulating material and an exposed portion of the layer of electrically-insulative programming layer material;
- forming a second layer of insulating material over the second exposed portion of the layer of insulating material, the exposed portion of the layer of electrically-insulative programming layer material and the top conductor layer;
- forming a first contact through the second layer of insulating material and the first layer of insulating material to the first conductive island, wherein the first contact is electrically coupled to the second conducting layer of the first conductive island;
- and
- forming a second contact through the second layer of insulating material, the top conductor layer and the first layer of insulating material to the second conductive island, wherein the second contact is electrically coupled to the top conductor layer.
12 more elements
Dependencies are inferred from the claim text.