Dual width contact for charge gain reduction

A method of forming a contact in an integrated circuit, the method comprising:

• providing a first insulating layer over a semiconductor substrate including first and second gate structures;
• providing an etch stop layer over the first insulating layer;
• providing a second insulating layer over the etch stop layer;
• creating a first aperture in the second insulating layer between the first and second gate structures, the first aperture having a first aperture width, the first aperture extending to the etch stop layer;
• creating a second aperture in the first insulating layer below the first aperture, the second aperture having a second aperture width, the second aperture width being less than the first aperture width;
• and
• filing the first and second apertures with a conductive material to form the contact;
• wherein the first and second gate structures include a floating gate section and the portion of the etch stop layer located proximate the contact is located at the same vertical position as the top of the floating gate section.

A method of forming a contact in an integrated circuit, the method comprising:

• providing a first insulating layer over a semiconductor substrate including first and second gate structures;
• providing an etch stop layer over the first insulating layer;
• providing a second insulating layer over the etch stop layer;
• creating a first aperture in the second insulating layer between the first and second gate structures, the first aperture having a first aperture width, the first aperture extending to the etch stop layer;
• creating a second aperture in the first insulating layer below the first aperture, the second aperture having a second aperture width, the second aperture width being less than the first aperture width;
• and
• filling the first and second apertures with a conductive material to form the contact;
• wherein the first and second gate structures include a floating gate section and the portion of the etch stop layer located proximate the contact is located above the vertical position of the top of the floating gate section.

A method of forming a dual width contact in an integrated circuit including gate structures and an insulating layer covering the gate structures, the method comprising:

• creating an aperture in the insulating layer extending through an etch stop layer to define a contact hole, the aperture having a first aperture width above the etch stop layer and a second aperture width below the etch stop layer, the second aperture width being less than the first aperture width;
• removing a portion of the etch stop layer;
• and
• providing a contact which fills the contact hole;
• wherein the gate structures include a floating gate section and wherein the etch stop layer is located at the same vertical position as a top of the floating gate section.

A method of forming an integrated circuit having reduced charge gain and loss, the method comprising:

• depositing a first insulating layer over a semiconductor substrate including first and second gate structures, each of the gate structures including a control gate and a floating gate;
• depositing an etch stop layer above the first insulating layer;
• depositing a second insulating layer above the etch stop layer;
• removing a portion of the second insulating layer between the first and second gate structures to form a first contact hole, the first contact hole extending to the top of the etch stop layer and having a first width;
• removing a portion of the first insulating layer between the first and second gate structures and below the first contact hole to form a second contact hole, the second contact hole extending between the bottom of the etch stop layer and the substrate and having a second width, the entire second width being less than the first width;
• and
• introducing a conductive material into the first and second contact holes to form a contact.

A method of forming an integrated circuit having produced charge gain and loss, the method comprising:

• depositing a first insulating layer over a semiconductor substrate including first and second gate structures, each of the gate structures including a control gate and a floating gate;
• depositing an etch stop layer above the first insulating layer;
• depositing a second insulating layer above the etch stop layer;
• removing a portion of the second insulating layer between the first and second gate structures to form a first contact hole, the first contact hole extending to the top of the etch stop layer and having a first width;
• removing a portion of the etch stop layer;
• removing a portion of the first insulating layer between the first and second gate structures and below the first contact hole to form a second contact hole, the second contact hole extending between the bottom of the etch stop layer and the substrate and having a second width, the entire second width being less than the first width;
• and
• introducing a conductive material into the first and second contact holes to form a contact;
• wherein the removed portion of the etch stop layer is located at substantially the same vertical position as the top of the floating gate.

A method of forming an integrated circuit having reduced charge gain and loss, the method comprising:

• depositing a first insulating layer over a semiconductor substrate including first and second gate structures, each of the gate structures including a control gate and a floating gate;
• depositing an etch stop layer above the first insulating layer;
• depositing a second insulating layer above the etch stop layer;
• removing a portion of the second insulating layer between the first and second gate structures to form a first contact hole, the first contact hole extending to the top of the etch stop layer and having a first width;
• removing a portion of the etch stop layer;
• removing a portion of the first insulating layer between the first and second gate structures and below the first contact hole to form a second contact hole, the second contact hole extending between the bottom of the etch stop layer and the substrate and having a second width, the entire second width being less than the first width;
• and
• introducing a conductive material into the first and second contact holes to form a contact;
• wherein the removed portion of the etch stop layer is located at a vertical position above the vertical position of the top of the floating gate.