CONTACT FOR ELECTRONIC COMPONENT
The present disclosure relates to a method for manufacturing a contact on a semiconductor region of an electronic component. The method includes forming a coating layer of dielectric material, with a thickness, on at least one side wall of an opening crossing through a dielectric region of the electronic component along a longitudinal direction from a first surface of the dielectric region, and opening out at the semiconductor region. The method includes forming of a metal filler layer, so as to fill the opening coated with the coatin
1 . A method for manufacturing a contact on a semiconductor region of an electronic component, the method comprising:
forming a coating layer of dielectric material, with a first thickness, on at least one side wall of an opening crossing through a dielectric region of the electronic component along a longitudinal direction from a first surface of the dielectric region, and opening out at the semiconductor region; and
forming a metal filler layer to fill the opening coated with the coating layer.
2 . The method according to claim 1 , further comprising:
forming a silicide interface layer comprising an interface between the semiconductor region and the contact; and
after forming the silicide interface layer, forming the opening through the dielectric region, wherein a width of the silicide interface layer is greater than a diameter of the opening.
3 . The method according to claim 1 , wherein the opening has a fixed cross-section, and the first thickness is determined for adapting an effective cross-section of the contact by reducing the cross-section of the opening.
4 . The method according to claim 1 , wherein the opening has a circular cylinder shape with a first diameter, the contact having a circular cylinder shape of a second diameter smaller than the first diameter, and the first thickness is determined for adapting the second diameter by reducing the first diameter by at least twice the first thickness.
5 . The method according to claim 1 , further comprising forming a diffusion barrier layer at a bottom of the opening and laterally in the opening on the coating layer, the formation of the diffusion barrier layer being carried out after forming the coating layer and before forming the filling layer.
6 . The method according to claim 1 , wherein forming the metal filler layer comprises:
depositing a metal layer from the first surface of the dielectric region; and
removing a portion of the metal layer extending over the openings and the first surface of the dielectric region to make the contact flush with the first surface.
7 . The method according to claim 6 , wherein removing the portion of the metal layer comprises a chemical mechanical polishing.
8 . The method according to claim 1 , wherein the dielectric material of the coating layer, or of the layer of dielectric material, is chosen from one or a plurality of materials among: silicon nitride, silicon oxide, silicon oxycarbide, silicon oxycarbonitride, or silicon carbonitride; and/or the metal of the filler layer, or of the metal layer, is chosen among tungsten or copper.
9 . The method according to claim 1 , wherein the first thickness of the coating layer is greater than or equal to 50 nm, wherein the opening has a diameter in a range 225 to 275 nm.
10 . A method for manufacturing a contact on a semiconductor region of an electronic component, the method comprising:
forming a coating layer of dielectric material, with a first thickness, on at least one side wall of an opening crossing through a dielectric region of the electronic component along a longitudinal direction from a first surface of the dielectric region, and opening out at the semiconductor region; and
forming a metal filler layer to fill the opening coated with the coating layer, wherein forming the coating layer comprises:
depositing a layer of dielectric material from the first surface of the dielectric region, at least on the side walls and at a bottom of the opening; and
removing by etching of a portion of the layer of dielectric material located at the bottom of the opening.
11 . The method according to claim 10 , further comprising:
forming a silicide interface layer comprising an interface between the semiconductor region and the contact; and
after forming the silicide interface layer, forming the opening through the dielectric region, wherein a width of the silicide interface layer is greater than a diameter of the opening.
12 . The method according to claim 10 , wherein the removing by etching further comprises removing a portion of the dielectric material layer located on the first surface of the dielectric region.
13 . The method according to claim 10 , wherein the etching is an anisotropic plasma etching and etches the dielectric material layer along the longitudinal direction.
14 . The method according to claim 10 , wherein the opening has a fixed cross-section, the method further comprising determining the first thickness for adapting an effective cross-section of the contact by reducing the cross-section of the opening.
15 . An electronic device comprising:
an electronic component comprising at least one contact on a semiconductor region of the electronic component, each contact being positioned in an opening crossing through a dielectric region of the electronic component along a longitudinal direction from a first surface of the dielectric region, and opening out at the semiconductor region, the contact comprising a coating layer of dielectric material, with a first thickness, extending along at least one side wall of the opening and a filler layer of metal in the opening coated with the coating layer.
16 . The electronic device according to claim 15 , further comprising a diffusion barrier layer at a bottom of the opening and laterally in the opening between the coating layer and the filler layer.
17 . The electronic device according to claim 15 , further comprising an air cavity, crossing through an interconnection region of the electronic component and the dielectric region near the contact.
18 . The electronic device according to claim 15 , wherein the dielectric material of the coating layer, or of the coating layer of dielectric material, is chosen from one or a plurality of materials among: silicon nitride, silicon oxide, silicon oxycarbide, silicon oxycarbonitride, or silicon carbonitride; and/or the metal of the filler layer, or of the metal layer, is chosen among tungsten or copper.
19 . The electronic device according to claim 15 , wherein the first thickness of the coating layer is greater than or equal to 50 nm.
20 . The electronic device according to claim 15 , wherein the electronic component comprises a silicide interface layer forming an interface between the semiconductor region and the contact, wherein a width of the silicide interface layer is greater than a diameter of the opening.
21 . The electronic device according to claim 15 , wherein the opening has a diameter between 225 nm and 275 nm.