US 6,713,872 B2Granted

Multilayered semiconductor device

AssigneeRenesas Technology Corp.

InventorYoshinori Tanaka

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Abstract

A first silicon oxide film is formed in such a manner as to cover source/drain regions of a transistor. A conductive pad is provided in the first silicon oxide film in such a manner that one end surface thereof is connected to each source/drain region and the other end surface thereof is exposed to the surface of the first silicon oxide film. A second silicon oxide film is formed on the first silicon oxide film and the pad. A conductive layer functioning as plug is provided in the second silicon oxide film in such a manner that one end surface thereof is in contact with the pad and the other end surface thereof is connected to an interconnection layer. The surface of the first silicon oxide film is smoothly continuous to the other end surface of the pad at the same level. The conductive layer as the plug is formed in such a manner as to be smaller in size than the pad and to be in contact with the central portion of the pad.

Claims6

Dependent claims

A semiconductor device in which first and second circuit elements to be connected to each other are disposed in such a manner as to be spaced from each other with a specific gap kept therebetween in the stacking direction, said semiconductor device comprising:

a first interlayer insulating film formed on said first circuit element, and wherein said first circuit element is a source/drain region of a transistor provided on a silicon substrate;
a conductive pad provided in said first interlayer insulating film in such a manner that one end surface thereof is connected to said first circuit element and the other end surface thereof is exposed to the surface of said first interlayer insulating film;
a second interlayer insulating film formed on said first interlayer insulating film and said pad;
and
a conductive plug provided in said second interlayer insulating film in such a manner that one end surface thereof is in contact with said pad and the other end surface thereof is connected to said second circuit element, and wherein said second circuit element is an interconnection layer,
wherein the surface of said first interlayer insulating film is smoothly continuous to the other end surface of said pad at the same level, said plug is smaller in size than said pad and is in contact with the central portion of said pad, and said interconnection layer is narrower than said conductive plug, and has a uniform width.

3 more elements

A semiconductor device having a capacitor over bit line structure in which a capacitor is provided on a bit line, said semiconductor device comprising:

a transistor formed on a silicon substrate, said transistor including two source/drain regions and a gate electrode held therebetween;
a first interlayer insulating film formed on said transistor;
an interconnection side pad provided in said first interlayer insulating film in such a manner that one end surface thereof is connected to one of said source/drain regions and the other end surface thereof is exposed to the surface of said first interlayer insulating film;
a capacitor side pad provided in said first interlayer insulating film in such a manner that one end surface thereof is connected to the other of said source/drain regions and the other end surface thereof is exposed to the surface of said first interlayer insulating film;
a second interlayer insulating film formed on said first interlayer insulating film and said two pads;
a bit line formed on said second interlayer insulating film;
an interconnection side plug provided in said second interlayer insulating film in such a manner that one end surface thereof is in contact with said interconnection side pad and the other end surface thereof is connected to said bit line;
a third interlayer insulating film formed on said bit line and said second interlayer insulating film;
a first electrode for a capacitor, which is formed on said third interlayer insulating film;
and
a capacitor side plug provided in said third interlayer insulating film in such a manner that one end surface thereof is in contact with said capacitor side pad and the other end surface thereof is connected to said first electrode,
wherein the surface of said first interlayer insulating film is smoothly continuous to the other end surfaces of said two pads at the same level;
said interconnection side plug is smaller in size than said interconnection side pad, and is in contact with the central portion of said interconnection side pad;
said capacitor side plug is in contact with said capacitor side pad;
said interconnection side pad is made from doped silicon;
said interconnection side plug comprises a high melting point metal film being in contact with said interconnection side pad and a low resistance metal film formed on said high melting point metal side film;
a silicide film is formed near the boundary between said interconnection side pad and said interconnection side plug;
said silicide film is formed by reaction between said interconnection side pad and a first high melting point metal film suitable for preventing absorption of an impurity from said doped silicon;
and
said high melting point metal film constituting part of said interconnection plug is a second high melting point metal film suitable for preventing reaction between said doped silicon and said low resistance metal film.

17 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/114,264Filed 3 Apr 2002 · continuation
Priority: JP 11-15285031 May 1999
Published: US 2002/0105089 A18 Aug 2002
Granted: 30 Mar 2004
Term ends: Not estimatedThe source records don’t support an estimate.

Classification20 codes

H10B 12/0335
The capacitor extending over the transistor: making a connection between the transistor and the capacitor, e.g. plug
H10W 20/066
By modifying the conductivity of conductive parts, e.g. by alloying: by forming silicides of refractory metals
H10W 20/069
Of conductive parts of the interconnections: by forming self-aligned vias or self-aligned contact plugs
H10W 20/0698
Of conductive parts of the interconnections: local interconnections