Layer structure of a memory cell for a dynamic random access memory device and method for producing the same

Claim 1

A layer structure of a memory cell for a dynamic random access memory device comprising a semiconductor substrate (11), and an insulation film (13, 17) formed on the semiconductor substrate having a first window (18A, 27A) through which a surface of the semiconductor substrate (11) is partially exposed, characterized in that the layer structure comprises a first conductive film (18 1A , 18 1B , 28 1A , 28 1B ) formed on the insulation film so as to surround the contact window (18A, 27A) and form a second window (18A, 28A) above the first window (18A, 27A); a second conductive film (25 1A , 25 1B , 35 1A , 35 1B ) formed so as to be in contact with the first conductive film (18 1A , 18 1B , 28 1A , 28 1B ) and the semiconductor substrate (11) through the first and second windows (18A, 27A, 28A), the first and second conductive films constructing a storage electrode of a memory cell capacitor; a dielectric film (19 1A , 19 1B , 29 1A , 29 1B ) formed so as to cover the storage electrode (18 1A , 18 1B , 28 1A , 28 1B , 25 1A 25 1B , 35 1A , 35 1B ); and a third conductive film (30₁) formed so as to cover the dielectric film (19 1A , 19 1B , 29 1A , 29 1B ).

Claim 9

A method of producing a layer structure of a memory cell for dynamic random access memory device, characterized by comprising the steps of forming an insulation film (13, 17) on a semiconductor substrate (11); forming a first conductive film (18) on the insulation film (13, 17), the first conductive film (18) being used for forming a part of a storage electrode of a memory cell capacitor; patterning the first conductive film (18) and the insulation film (13, 17) so as to form a window (l8A, 27A, 28A) used for forming a contact between the storage electrode and the semiconductor substrate (11); forming a second conductive film (25) so as to cover the window (18A, 27A, 28A) and the first conductive film (18), the second conductive film being use for forming the remaining part of the storage electrode; and patterning the first conductive film (18) and the second conductive film (25), patterned first and second conductive films (18 1A , 18 1B , 28 1A , 28 1B , 25 1A , 25 1B , 35 1A , 35 1B ) constructing the storage electrode; forming a dielectric film (19 1A , 19 1B , 29 1A , 29 1B ) so as to cover the storage electrode; and forming a third conductive (30₁) film so as to cover the dielectric film (19 1A , 19 1B , 29 1A , 29 1B ), the third conductive film (30₁) being an opposed electrode which is paired with the storage electrode of the memory cell capacitor.

Claim 10

A method of producing a layer structure of a memory cell for dynamic random access memory device, characterized by comprising the steps of forming an insulation film (13, 17) on a semiconductor substrate (11); forming a first conductive film (18) on the insulation film (13, 17), the first conductive film (18) being used for forming a part of a storage electrode of a memory cell capacitor; patterning the first conductive film (18) and the insulation film (13, 17) so as to form a window (l8A, 27A, 28A) used for forming a contact between the storage electrode and the semiconductor substrate (11); forming a second conductive film (25) so as to cover the window (18A, 27A, 28A) and the first conductive film (18), the second conductive film being use for forming the remaining part of the storage electrode; and patterning the first conductive film (18) and the second conductive film (25), patterned first and second conductive films (18 1A , 18 1B , 28 1A , 28 1B , 25 1A , 25 1B , 35 1A , 35 1B ) constructing the storage electrode; forming a dielectric film (19 1A , 19 1B , 29 1A , 29 1B ) so as to cover the storage electrode; and forming a third conductive (30₁) film so as to cover the dielectric film (19 1A , 19 1B , 29 1A , 29 1B ), the third conductive film (30₁) being an opposed electrode which is paired with the storage electrode of the memory cell capacitor.