CN117038649A - Capacitor structure and forming method thereof - Google Patents

Abstract

A capacitor structure and method of forming the same, the method comprising: providing a substrate; forming a plurality of layers of metal wires on a substrate, wherein the metal wires of each layer comprise a first electrode and a second electrode which are alternately stacked on the substrate in sequence, each of the first electrode and the second electrode comprises a comb handle part and a plurality of comb tooth parts which are connected with the comb handle part and are arranged in parallel, the comb tooth parts corresponding to the first electrode are used as first comb tooth parts, and the comb tooth parts corresponding to the second electrode are used as second comb tooth parts; among the metal wires of the adjacent layers, the projection of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, and the projection of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts. The capacitance density of the capacitor structure is improved.

Description

Capacitor structure and forming method thereof

Technical Field

Embodiments of the present disclosure relate to the field of semiconductor manufacturing, and more particularly, to a capacitor structure and a method for forming the same.

Background

Metal-oxide-Metal (MOM) capacitors are a number of very critical components in mixed-signal Radio Frequency Integrated Circuits (RFICs), such as analog frequency tuning circuits, switched capacitor circuits (Switched Capacitor Circuits), filters, resonators (modulators), up-and Down-modulation (Down-conversion) mixers, analog-to-digital Converters (a/D Converters), and the like, which serve as internal matching (inter-matching) to greatly optimize the performance of the RFICs.

However, the performance of Metal-oxide-Metal (MOM) capacitor structures remains to be improved.

Disclosure of Invention

The embodiment of the invention solves the problem of providing a capacitor structure and a forming method thereof. The performance of the capacitor is further improved.

To solve the above problems, an embodiment of the present invention provides a capacitor structure, including: a substrate; the multi-layer metal wire comprises a first metal wire and a second metal wire which are sequentially and alternately stacked on the substrate and are electrically connected with each other, each layer of metal wire comprises a first electrode and a second electrode, each of the first electrode and the second electrode comprises a comb handle part and a plurality of comb tooth parts which are connected with the comb handle part and are arranged in parallel, the comb tooth part corresponding to the first electrode is used as a first comb tooth part, the comb tooth part corresponding to the second electrode is used as a second comb tooth part, and the second comb tooth part and the first comb tooth part are arranged in a crossing way; among the metal wires of the adjacent layers, the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the first comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are contacted, and the projections of the second comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are contacted.

Correspondingly, the embodiment of the invention provides a method for forming a capacitor structure, which comprises the following steps: providing a substrate; forming a plurality of layers of metal wires on the substrate, wherein the plurality of layers of metal wires comprise a first metal wire and a second metal wire which are sequentially and alternately stacked on the substrate and are electrically connected with each other, each layer of metal wire comprises a first electrode and a second electrode, each of the first electrode and the second electrode comprises a comb handle part and a plurality of comb teeth parts which are connected with the comb handle part and are arranged in parallel, each comb tooth part corresponding to the first electrode is used as a first comb teeth part, each comb tooth part corresponding to the second electrode is used as a second comb teeth part, and each second comb teeth part is arranged in a crossing way with each first comb teeth part; among the metal wires of the adjacent layers, the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are contacted, and the projections of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are contacted.

Compared with the prior art, the technical scheme of the embodiment of the invention has the following advantages:

the embodiment of the invention provides a method for forming a capacitor, wherein in metal wires of adjacent layers, projections of first comb tooth parts corresponding to first metal wires and first comb tooth parts corresponding to second metal wires on a substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, projections of second comb tooth parts corresponding to first metal wires and second comb tooth parts corresponding to second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, projections of first comb tooth parts corresponding to first metal wires and first comb tooth parts corresponding to second metal wires on the substrate are contacted with each other, and projections of second comb tooth parts corresponding to first metal wires and second comb tooth parts corresponding to second metal wires on the substrate are contacted with each other. Compared with the prior art that the first metal wires and the second metal wires are stacked alternately in turn, and the first comb tooth parts and the second comb tooth parts of the adjacent layers are positioned right above or right below each other, in the metal wires of the adjacent layers, the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are staggered along the arrangement direction of the comb tooth parts, the projections of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are staggered along the arrangement direction of the comb tooth parts, and the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are contacted, the projection of the second comb tooth portion corresponding to the first metal wire and the projection of the second comb tooth portion corresponding to the second metal wire on the substrate are contacted, so that the total effective coupling distance between the first electrode of the first metal wire and the second electrode of the second metal wire of the adjacent layer is reduced, the total effective coupling distance between the second electrode of the first metal wire and the first electrode of the second metal wire of the adjacent layer is reduced, the total capacitance value between the first electrode of the first metal wire and the second electrode of the second metal wire of the adjacent layer is increased, the total capacitance value between the second electrode of the first metal wire and the first electrode of the second metal wire of the adjacent layer is increased, correspondingly, the capacitance value between the plurality of layers of metal wires which are sequentially and alternately stacked on the substrate and are electrically connected with each other is increased, thereby improving the capacitance density of the capacitor structure, thereby improving the performance of the capacitor structure.

Drawings

Fig. 1 to 3 are schematic structural views of a capacitor structure;

FIGS. 4-6 are schematic diagrams illustrating capacitor structures according to one embodiment of the present invention;

fig. 7 to 10 are schematic structural diagrams corresponding to steps in an embodiment of a method for forming a capacitor structure according to the present invention.

Detailed Description

The performance of the present capacitor structure is to be improved. The reasons for the improvement in performance are now analyzed in connection with a capacitor structure.

Fig. 1 to 3 are schematic structural views corresponding to a capacitor structure, wherein fig. 1 is a top view of the capacitor structure, fig. 2 is a cross-sectional view of fig. 1 along the direction ef, and fig. 3 is a cross-sectional view of fig. 1 along the direction gh.

Referring to fig. 1 to 3, the capacitor structure includes: a substrate 10; a stacked multi-layered metal wire 20 positioned on top of the substrate 10, the metal wire 20 including a first electrode 18 and a second electrode 13, the first electrode 18 including a first comb handle portion 17 and a plurality of first comb teeth portions 16 connected to the first comb handle portion 17, the second electrode 13 including a second comb handle portion 11 and a plurality of second comb teeth portions 12 connected to the second comb handle portion 11, the second comb teeth portions 12 being disposed to intersect the first comb teeth portions 11, and the lengths of the plurality of first comb teeth portions 11 being the same as the lengths of the plurality of second comb teeth portions 12; a first via interconnect structure 21 located between the first comb handle portions 17 of the adjacent layers of the metal layer 20, and the first via interconnect structure 21 is electrically connected to the first comb handle portions 17; a second via interconnect structure 22 is located between the second comb handle portions 11 of the adjacent layers of the metal layer 20, and the first via interconnect structure 22 is electrically connected with the first comb handle portions 11.

In the adjacent two metal wires 20, the first electrode 18 and the second electrode 13 are disposed opposite to each other in the longitudinal direction, so that the total effective coupling distance between the first electrode 18 of any metal wire 20 and the second electrode 13 of the adjacent metal wire 20 in the capacitor is too large, and thus the total capacitance value between the first electrode 18 and the second electrode 13 of the adjacent metal wire is too small, and accordingly, the capacitance value between the multiple metal wires 20 stacked alternately and disposed on the substrate 10 and electrically connected to each other is reduced, and in the case of a certain volume of the capacitor structure, the capacitance density of the capacitor structure is too low, thereby affecting the performance of the capacitor structure.

For example, as shown in fig. 3, for two adjacent metal lines 20, since the first electrode 18 and the second electrode 13 are disposed opposite to each other in the longitudinal direction, the coupling distance between the second electrode 13 of one metal line 20 and the first electrode 18 adjacent in the oblique direction is large, so that the total capacitance C2 between the second electrode 13 and the first electrode 18 is too small.

In order to solve the technical problem, an embodiment of the present invention provides a method for forming a capacitor structure, including: providing a substrate; forming a plurality of layers of metal wires on the substrate, wherein the plurality of layers of metal wires comprise a first metal wire and a second metal wire which are sequentially and alternately stacked on the substrate and are electrically connected with each other, each layer of metal wire comprises a first electrode and a second electrode, each of the first electrode and the second electrode comprises a comb handle part and a plurality of comb teeth parts which are connected with the comb handle part and are arranged in parallel, each comb tooth part corresponding to the first electrode is used as a first comb teeth part, each comb tooth part corresponding to the second electrode is used as a second comb teeth part, and each second comb teeth part is arranged in a crossing way with each first comb teeth part; among the metal wires of the adjacent layers, the projection of the first comb tooth part corresponding to the first metal wire and the projection of the second comb tooth part corresponding to the second metal wire on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projection of the second comb tooth part corresponding to the first metal wire and the projection of the first comb tooth part corresponding to the second metal wire on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projection of the first comb tooth part corresponding to the first metal wire and the projection of the second comb tooth part corresponding to the second metal wire on the substrate are contacted, and the projection of the second comb tooth part corresponding to the first metal wire and the projection of the first comb tooth part corresponding to the second metal wire on the substrate are contacted.

The embodiment of the invention provides a method for forming a capacitor structure, wherein projections of first comb tooth parts corresponding to first metal wires and second comb tooth parts corresponding to second metal wires on a substrate are arranged in a staggered manner along the arrangement direction of the comb tooth parts, projections of the second comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered manner along the arrangement direction of the comb tooth parts, the projections of the first comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered manner, and the projections of the first comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are in contact with each other.

In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

Fig. 4 to 6 are schematic structural views of an embodiment of the capacitor structure of the present invention, in which fig. 4 is a top view, fig. 5 is a cross-sectional view of fig. 4 along AB direction, and fig. 6 is a cross-sectional view of fig. 4 along CD direction.

The semiconductor structure comprises: a substrate 200; a plurality of metal wires 213 including first metal wires 212 and second metal wires 211 which are sequentially and alternately stacked on the substrate 200 and are electrically connected to each other, wherein each metal wire 213 includes a first electrode 207 and a second electrode 208, each of the first electrode 207 and the second electrode 208 includes a comb handle 201, and a plurality of comb teeth 202 connected to the comb handle 201 and arranged in parallel, each of the comb teeth 202 corresponding to the first electrode 207 is a first comb teeth 203, each of the comb teeth 202 corresponding to the second electrode 208 is a second comb teeth 206, and each of the second comb teeth 206 is disposed to cross the first comb teeth 203; among the metal wires 213 of the adjacent layers, the projections of the first comb-tooth portions 203 corresponding to the first metal wires 212 and the projections of the first comb-tooth portions 203 corresponding to the second metal wires 211 on the substrate 200 are staggered along the arrangement direction of the comb-tooth portions 202, the projections of the second comb-tooth portions 206 corresponding to the first metal wires 212 and the projections of the second comb-tooth portions 206 corresponding to the second metal wires 211 on the substrate 200 are staggered along the arrangement direction of the comb-tooth portions 202, the projections of the first comb-tooth portions 203 corresponding to the first metal wires 212 and the projections of the first comb-tooth portions 203 corresponding to the second metal wires 211 on the substrate are contacted, and the projections of the second comb-tooth portions 206 corresponding to the first metal wires 212 and the projections of the second comb-tooth portions 206 corresponding to the second metal wires 211 on the substrate are contacted.

Specifically, among the metal wires of the adjacent layers, the projections of the first comb-tooth portions 203 corresponding to the first metal wires 212 and the projections of the first comb-tooth portions 203 corresponding to the second metal wires 211 on the substrate 200 are arranged in a staggered manner along the arrangement direction of the comb-tooth portions 202, the projections of the second comb-tooth portions 206 corresponding to the first metal wires 212 and the second comb-tooth portions 206 corresponding to the second metal wires 211 on the substrate 200 are arranged in a staggered manner along the arrangement direction of the comb-tooth portions 202, the projections of the first comb-tooth portions 203 corresponding to the first metal wires 212 and the first comb-tooth portions 203 corresponding to the second metal wires 211 on the substrate 200 are contacted, the projections of the second comb-tooth portions 206 corresponding to the first metal wires 212 and the second comb-tooth portions 206 corresponding to the second metal wires 211 on the substrate 200 are contacted, the total effective coupling distance between the first electrode 207 of the first metal line 212 and the second electrode 208 of the second metal line 211 of its adjacent layer is made smaller, and the total effective coupling distance between the second electrode 208 of the first metal line 212 and the first electrode 207 of the second metal line 211 of its adjacent layer is made smaller, so that the total capacitance value between the first electrode 207 of the first metal line 212 and the second electrode 208 of the second metal line 211 of its adjacent layer is increased, and the total capacitance value between the second electrode 208 of the first metal line 212 and the first electrode 207 of the second metal line 211 of its adjacent layer is increased, and accordingly, the capacitance value between the multilayer metal lines 213 which are sequentially and alternately stacked on the substrate 200 and electrically connected to each other is made larger, thereby improving the capacitance density of the capacitor structure, and further improving the performance of the capacitor structure.

For example, as shown in fig. 6, taking the first electrode 207 of the second metal line 211 as an example, for the metal line 213 of the adjacent layer, the sum of effective coupling distances between the first electrode 207 of the second metal line 211 and the adjacent second electrode 208 in the oblique direction becomes smaller, and thus the total capacitance value C2 between the first electrode 207 of the first metal line 212 and the second electrode 208 of the second metal line 211 of the adjacent layer increases. Similarly, the total capacitance value between the second electrode of the first metal line 212 and the first electrode of the second metal line 211 of the adjacent layer increases.

In order to facilitate distinguishing the first electrode 207 of the second metal line 211 from the second electrode 208 of the second metal line 211, as shown in fig. 6, the contour line thickness of the first electrode 207 and the second electrode 208 of the second metal line 211 is different; similarly, in order to facilitate distinguishing between the first electrode 207 of the first metal line 212 and the second electrode 208 of the first metal line 212, the contour line thickness of the first electrode 207 and the second electrode 208 of the first metal line 212 is different.

In this embodiment, the substrate 200 is used to form a capacitor with a plurality of metal lines 213 disposed on top of the substrate 200.

In this embodiment, the base 200 may include doped or undoped silicon, or an active layer of a semiconductor-on-insulator (SOI) substrate. In other embodiments, the material of the base may also be germanium, silicon carbide, gallium arsenide, or indium gallium arsenide, and the base may also be a silicon-on-insulator substrate or a germanium-on-insulator substrate.

In this embodiment, in the metal line 213 of the same layer, the first electrode 207 and the second electrode 208, which are disposed so as to intersect the first comb-teeth portion 203, form an electrode group 210.

Specifically, since the input electrical signals of the first electrode 208 and the second electrode 203 are opposite, and the inter-Metal dielectric layer 215 between the electrode groups 110 and the electrode groups 210 form a Metal-oxide-Metal (MOM) capacitor.

In this embodiment, the number of the electrode groups 210 is plural, and the arrangement direction of the plurality of electrode groups 210 is perpendicular to the extending direction of the comb handle 201, and adjacent electrode groups 210 share the comb handle 201 at the boundary.

It should be noted that, the arrangement direction of the plurality of electrode groups 210 is perpendicular to the extension direction of the comb handle 201, that is, the arrangement direction of the plurality of electrode groups 210 is the same as the extension direction of the comb teeth 202, and in a case where the volume of the MOM capacitor is fixed, the more the electrode groups 210 are arranged along the extension direction of the comb teeth 202, the smaller the length of the comb teeth 202 in each electrode group 210, and when an electrical signal passes through the comb teeth 202, the smaller the length of the comb teeth 102, and the smaller the attenuation amplitude of the electrical signal passing through the comb teeth 202, so as to reduce the probability that the capacitance value generated between the comb teeth 202 of the same layer fluctuates and the capacitance value generated between the comb teeth 202 of adjacent layers fluctuates. As an example, the number of the electrode groups 210 is two.

It should be further noted that, the adjacent electrode groups 210 share the comb handle 201 at the junction, which is beneficial to improving the structural integration of the MOM capacitor, so that the overall structure of the MOM capacitor is more compact.

In this embodiment, in the metal wires 213 of the adjacent layers, the comb handle 201 of the second metal wire 211 is located directly above the comb handle 201 of the first metal wire 212.

On the one hand, since the lengths of the comb teeth 202 of the second metal wire 211 and the lengths of the comb teeth 202 of the first metal wire 212 are both identical, and the lengths of the comb teeth 202 of the second metal wire 211 and the widths of the comb teeth 202 of the first metal wire 212 are both identical, the comb handle 201 of the second metal wire 211 is located directly above the comb handle 201 of the first metal wire 212, so that the total coupling area between the first electrode 207 of the first metal wire 212 and the second electrode 208 of the second metal wire 211 of the adjacent layer is maximized, and the total coupling area between the second electrode 108 of the first metal wire 212 and the first electrode 207 of the second metal wire 211 of the adjacent layer is maximized, and accordingly, the total capacitance value between the first electrode 207 of the first metal wire 212 and the second electrode 208 of the second metal wire 211 of the adjacent layer is increased, and the total capacitance value between the second electrode 208 of the first metal wire 212 and the first electrode 208 of the second metal wire 211 of the adjacent layer is increased, and the capacitance value of the capacitor density of m is increased.

On the other hand, in the metal wires 213 of the adjacent layers, the comb handle 201 of the second metal wire 211 is located directly above the comb handle 201 of the first metal wire 212, so that the structural symmetry of the multi-layer metal wires 213 in the MOM capacitor is high, and the probability of frequency oscillation of the MOM capacitor is reduced, thereby improving the performance of the capacitor structure.

In this embodiment, along the normal direction of the surface of the substrate 200, the side walls of the first comb teeth 203 and the side walls of the second comb teeth 206 of the adjacent layers are flush, so that the total effective coupling distance between the first electrode 207 of the first metal wire 212 and the second electrode 208 of the second metal wire 211 of the adjacent layers is reduced, and the total effective coupling distance between the second electrode 208 of the first metal wire 212 and the first electrode 207 of the second metal wire 211 of the adjacent layers is reduced, and accordingly, the total capacitance value between the first electrode 207 of the first metal wire 212 and the second electrode 208 of the second metal wire 211 of the adjacent layers is increased, and the total capacitance value between the second electrode 208 of the first metal wire 212 and the first electrode 207 of the second metal wire 211 of the adjacent layers is increased.

In other embodiments, the side walls of the first comb teeth portions and the second comb teeth portions of the adjacent layers may not be flush, and the projections of the first comb teeth portions and the second comb teeth portions of the adjacent layers on the substrate have partial overlapping areas.

In this embodiment, the number of layers of the first metal lines 212 is multiple, and the projections of the first metal lines 212 on the surface of the substrate 200 are coincident.

It should be noted that, the greater the number of layers of the stacked first metal lines 212, the greater the total capacitance value between the first electrode 207 and the second electrode 208 of the adjacent first metal lines 212, and, at the same time, since the second metal lines 211 are further disposed between the adjacent first metal lines 212, when the number of layers of the first metal lines 212 is multiple, the number of layers of the second metal lines 211 is also multiple, and accordingly, the greater the total capacitance value generated between the first electrode 207 of the first metal line 212 and the second electrode 208 of the second metal line 211 of the adjacent layer is, the greater the total capacitance value generated between the second electrode 208 of the first metal line 212 and the first electrode 207 of the second metal line 211 of the adjacent layer is, thereby increasing the capacitance value of the MOM capacitor.

It should be further noted that the projections of the first metal lines 212 on the surface of the substrate 200 coincide, so that the total coupling area between the first electrodes 207 and the second electrodes 208 in the adjacent first metal lines 212 is maximized, and accordingly, the capacitance value generated between the first electrodes 207 and the second electrodes 208 in the adjacent first metal lines 212 is maximized, thereby increasing the capacitance density of the capacitor structure.

In this embodiment, the number of layers of the second metal lines 211 is multiple, and projections of the second metal lines 211 on the surface of the substrate 200 are coincident.

It should be noted that, the greater the number of layers of the stacked second metal lines 211, the greater the total capacitance value between the first electrode 207 and the second electrode 208 of the adjacent second metal lines 211, and, at the same time, since the first metal lines 212 are further disposed between the adjacent second metal lines 211, when the number of layers of the second metal lines 211 is multiple, the number of layers of the first metal lines 212 is also multiple, and accordingly, the greater the total capacitance value generated between the first electrode 207 of the first metal line 212 and the second electrode 208 of the second metal line 211 of the adjacent layer is, the greater the total capacitance value generated between the second electrode 208 of the first metal line 212 and the first electrode 207 of the second metal line 211 of the adjacent layer is, thereby increasing the capacitance value of the MOM capacitor.

It should be further noted that the projections of the second metal lines 211 on the surface of the substrate 100 overlap, so as to maximize the total coupling area between the first electrodes 207 and the second electrodes 208 in the adjacent second metal lines 211, and correspondingly, maximize the capacitance value generated between the first electrodes 207 and the second electrodes 208 in the adjacent second metal lines 211, thereby increasing the capacitance density of the capacitor structure.

In this embodiment, the material of the first metal line 212 includes one or more of aluminum, copper, titanium nitride, tantalum nitride, and cobalt.

Specifically, the aluminum, copper, titanium nitride, tantalum nitride and cobalt have lower resistivity, which is favorable for making the resistance value generated by the first metal line 212 lower, so that the performance of the capacitor structure is improved, and meanwhile, the electron mobility of the aluminum, copper, titanium nitride, tantalum nitride and cobalt is faster, the conductivity is higher, and the electrical performance of the capacitor structure can be further improved.

In this embodiment, the material of the second metal line 211 includes one or more of aluminum, copper, titanium nitride, tantalum nitride and cobalt.

Specifically, the aluminum, copper, titanium nitride, tantalum nitride and cobalt have lower resistivity, which is favorable for making the resistance value generated by the first metal line 212 lower, so that the performance of the capacitor structure is improved, and meanwhile, the electron mobility of the aluminum, copper, titanium nitride, tantalum nitride and cobalt is faster, the conductivity is higher, and the electrical performance of the capacitor structure can be further improved.

In this embodiment, the capacitor structure further includes: a via interconnect structure 216 is located between the handle portions 201 of the metal lines 213 of adjacent layers and is electrically connected to the handle portions 201.

Specifically, the via interconnection structure 216 is configured to electrically connect the stacked layers of the first metal line 212 and the second metal line 211 to each other.

In this embodiment, the material of the via interconnect structure 216 includes one or more of aluminum, copper, titanium nitride, tantalum nitride, and cobalt.

Specifically, aluminum, copper, titanium nitride, cobalt and tantalum nitride have lower resistivity, which is beneficial to making the resistance value generated by the via interconnection structure 216 lower, improving the performance of the capacitor structure, and at the same time, aluminum, copper, titanium nitride, cobalt and tantalum nitride have faster electron mobility, have higher conductivity, and can further improve the electrical performance of the capacitor structure.

In this embodiment, the semiconductor structure further includes: an inter-metal dielectric layer 215 is located over the substrate 200 at the side of the first electrode 207 and the second electrode 208, and covers the sidewalls of the first electrode 207 and the second electrode 208.

The inter-metal dielectric layer 215 is interposed between the first electrode 207 and the second electrode 208, and the inter-metal dielectric layer 205 is configured to electrically isolate the adjacent first electrode 207 and second electrode 208, so as to reduce the probability of shorting between the first electrode 207 and the second electrode 208.

The inter-metal dielectric layer 215 is an insulating material, and the material of the inter-metal dielectric layer 215 includes one or more of silicon oxide, silicon nitride, silicon oxynitride, silicon oxycarbide, silicon carbonitride and silicon oxycarbonitride. As an example, the material of the intermetal dielectric layer 215 is silicon oxide.

Fig. 7 to 10 are schematic structural views corresponding to steps in an embodiment of a method for forming a semiconductor structure according to the present invention.

Referring to fig. 7, a substrate 100 is provided.

In this embodiment, the substrate 100 is used to form a capacitor with a plurality of metal lines formed on top of the substrate 100.

In this embodiment, the base 100 may include doped or undoped silicon, or an active layer of a semiconductor-on-insulator (SOI) substrate. In other embodiments, the material of the base may also be germanium, silicon carbide, gallium arsenide, or indium gallium arsenide, and the base may also be a silicon-on-insulator substrate or a germanium-on-insulator substrate.

Referring to fig. 8 to 10, fig. 8 is a top view after forming a multi-layer metal wire, fig. 9 is a cross-sectional view along a ab direction of fig. 8, fig. 10 is a cross-sectional view along a cd direction of fig. 8, forming a multi-layer metal wire 113 on the substrate 100, the multi-layer metal wire 113 including a first metal wire 112 and a second metal wire 111 which are sequentially and alternately stacked on the substrate 100 and are electrically connected to each other, the metal wire 113 of each layer includes a first electrode 107 and a second electrode 108, the first electrode 107 and the second electrode 108 each include a comb handle 101, and a plurality of parallel-arranged comb teeth 102 connected to the comb handle 101, the first electrode 107 corresponds to the comb teeth 102 as a first comb teeth 103, the second electrode 108 corresponds to the comb teeth 102 as a second comb teeth 106, the second comb teeth 106 are disposed across the first comb teeth 103, the metal wire 113 of an adjacent layer includes a first metal wire 107 and a second metal wire 108, the first metal wire 103 corresponds to the second metal wire 103 and the second metal wire 103 corresponds to the second comb wire 111 are disposed across the first comb teeth 106 and the second comb teeth 106, the second metal wire 102 is disposed across the first comb teeth 106 and the second comb wire 102 and is disposed across the first comb teeth 106 and the second comb wire 106, and the second metal wire 102 is disposed across the first comb wire 103 and is disposed across the second comb wire 102 and is disposed across the second wire 102.

Specifically, in the metal wires 113 of the adjacent layers, the projections of the first comb-tooth portions 103 corresponding to the first metal wires 112 and the first comb-tooth portions 102 corresponding to the second metal wires 111 on the substrate 100 are arranged in a staggered manner along the arrangement direction of the comb-tooth portions 102, the projections of the second comb-tooth portions 106 corresponding to the first metal wires 112 and the second comb-tooth portions 106 corresponding to the second metal wires 111 on the substrate 100 are arranged in a staggered manner along the arrangement direction of the comb-tooth portions 102, and the projections of the first comb-tooth portions 103 corresponding to the first metal wires 112 and the first comb-tooth portions 103 corresponding to the second metal wires 111 on the substrate 100 are in contact, the projections of the second comb-tooth portions 106 corresponding to the first metal wires 112 and the second comb-tooth portions 106 corresponding to the second metal wires 111 on the substrate 100 are in contact, the total effective coupling distance between the first electrode 107 of the first metal line 112 and the second electrode 108 of the second metal line 111 of its adjacent layer is made smaller, and the total effective coupling distance between the second electrode 108 of the first metal line 112 and the first electrode 107 of the second metal line 111 of its adjacent layer is made smaller, so that the total capacitance value between the first electrode 107 of the first metal line 112 and the second electrode 108 of the second metal line 111 of its adjacent layer is increased, and the total capacitance value between the second electrode 108 of the first metal line 112 and the first electrode 107 of the second metal line 111 of its adjacent layer is increased, and correspondingly, the capacitance value between the multi-layer metal lines 113 which are sequentially and alternately stacked on the substrate 100 and electrically connected to each other is made larger, thereby improving the capacitance density of the capacitor structure, and further improving the performance of the capacitor structure.

In this embodiment, a plurality of metal patterning processes are performed to form the multi-layered metal line 113, where the metal patterning processes are used to form the metal line 113 with the same layer, and the metal patterning process includes: forming an inter-metal dielectric layer 115 on top of the substrate 100; forming comb-shaped first grooves (not shown) and second grooves (not shown) penetrating through the inter-metal dielectric layer 115, wherein each of the first grooves and the second grooves comprises comb handle grooves and comb tooth grooves which are communicated with the comb handle grooves and are arranged in parallel, the comb tooth grooves corresponding to the first grooves are used as first comb tooth grooves, the comb tooth grooves corresponding to the second grooves are used as second comb tooth grooves, and the second comb tooth grooves are arranged in an intersecting manner with the first comb tooth grooves; filling metal materials (not shown) in the first groove and the second groove to form a comb handle part 101 positioned in the comb handle groove and a comb tooth part 102 positioned in the comb tooth groove, wherein the comb handle part 101 and the comb tooth part 102 in the first groove form a first electrode 107, and the comb handle part 101 and the comb tooth part 102 in the second groove form a second electrode 108; the comb tooth grooves formed in the metal patterning process of the last time are arranged in a staggered manner with respect to the comb tooth parts 102 formed in the metal patterning process of the previous time along the arrangement direction, and the projection of the comb tooth grooves on the substrate is contacted with the projection of the comb tooth parts 102 on the substrate 100.

The inter-metal dielectric layer 115 is interposed between the first comb tooth 103 and the second comb tooth 106, and the inter-metal dielectric layer 105 is configured to electrically isolate the adjacent first comb tooth 103 and second comb tooth 106, so as to reduce the probability of shorting between the first comb tooth 103 and the second comb tooth 106, and meanwhile, the inter-metal dielectric layer 105 provides a spatial position for forming the first trench and the second trench.

The inter-metal dielectric layer 115 is an insulating material, and the material of the inter-metal dielectric layer 115 includes one or more of silicon oxide, silicon nitride, silicon oxynitride, silicon oxycarbide, silicon carbonitride, and silicon oxycarbonitride. As an example, the material of the intermetal dielectric layer 115 is silicon oxide.

In this embodiment, the process of forming the first electrode 107 in the first trench and the process of forming the second electrode 108 in the second trench each include an electrochemical plating (Electrochemical Plating) process.

Specifically, the electrochemical plating (Electrochemical Plating) process has the characteristics of fast growth rate, good filling performance, etc., reduces the probability of occurrence of gaps between the interfaces of the first electrode 107 and the second electrode 108 and the inter-metal dielectric layer 115, and improves the conductivity of the metal wire 113.

In this embodiment, the multi-layered metal line 113 is formed on the top of the substrate 100, and the patterning process is used to form one layer of the metal line 113, so that multiple patterning processes are required in the process of forming the multi-layered metal line 113 on the top of the substrate 100.

It should be noted that, in the next metal patterning process, the comb teeth slots formed in the next metal patterning process are arranged in a staggered manner with respect to the comb teeth 102 formed in the previous metal patterning process, and the projection of the comb teeth slots on the substrate 100 is in contact with the projection of the comb teeth 102 on the substrate 100, accordingly, the comb teeth 102 formed in the comb teeth slots formed in the next metal patterning process are arranged in a staggered manner with respect to the comb teeth 102 formed in the previous metal patterning process, so that the total effective coupling distance between the first electrode 107 of the first metal wire 112 and the second electrode 108 of the second metal wire 111 of the adjacent layer is reduced, and the total effective coupling distance between the second electrode 108 of the first metal wire 112 and the first electrode 107 of the second metal wire 111 of the adjacent layer is reduced, and correspondingly, the total capacitance value between the first electrode 107 of the first metal wire 112 and the second electrode 108 of the adjacent layer is increased, and the total capacitance value between the first electrode 108 of the first metal wire 112 and the second electrode 108 of the adjacent layer is increased, thereby increasing the total capacitance value of the capacitor structure.

In this embodiment, in the metal line 113 of the same layer, the first electrode 107 and the second electrode 108, which are disposed so as to intersect the first comb-teeth portion 103, form an electrode group 110.

Specifically, since the input electrical signals of the first electrode 108 and the second electrode 103 are opposite, and the inter-Metal dielectric layer 115 between the electrode groups 110 and the electrode groups 110 form a Metal-oxide-Metal (MOM) capacitor.

In this embodiment, the number of the electrode groups 110 is plural, and the arrangement direction of the plurality of electrode groups 110 is perpendicular to the extending direction of the comb handle 101, and adjacent electrode groups 110 share the comb handle 101 at the boundary.

It should be noted that, the arrangement direction of the plurality of electrode groups 110 is perpendicular to the extension direction of the comb handle 101, that is, the arrangement direction of the plurality of electrode groups 110 is the same as the extension direction of the comb teeth 102, and in a case that the volume of the MOM capacitor is fixed, the more the electrode groups 110 are arranged along the extension direction of the comb teeth 102, the smaller the length of the comb teeth 102 in each electrode group 110, and when an electrical signal passes through the comb teeth 102, the smaller the length of the comb teeth 102, and the smaller the attenuation amplitude of the electrical signal passing through the comb teeth 102, so as to reduce the probability that the capacitance value generated between the comb teeth 102 of the same layer fluctuates and the capacitance value generated between the comb teeth 102 of adjacent layers fluctuates. As an example, the number of the electrode groups 110 is two.

It should be further noted that, the adjacent electrode groups 110 share the comb handle 101 at the junction, which is beneficial to improving the structural integration level of the MOM capacitor, so that the overall structure of the MOM capacitor is more compact.

In this embodiment, in the metal wires 113 of the adjacent layers, the comb handle portion 101 of the second metal wire 111 is located directly above the comb handle portion 101 of the first metal wire 112.

On the one hand, since the lengths of the comb teeth 102 of the second metal wire 111 are the same as the lengths of the comb teeth 102 of the first metal wire 112, and the lengths of the comb teeth 102 of the second metal wire 111 are the same as the widths of the comb teeth 102 of the first metal wire 112, the comb handle 101 of the second metal wire 111 is located directly above the comb handle 101 of the first metal wire 112, so that the total coupling area between the first electrode 107 of the first metal wire 112 and the second electrode 108 of the second metal wire 111 of the adjacent layer is maximized, and the total coupling area between the second electrode 108 of the first metal wire 112 and the first electrode 107 of the second metal wire 111 of the adjacent layer is maximized, and accordingly, the total capacitance value between the first electrode 107 of the first metal wire 112 and the second electrode 108 of the second metal wire 111 of the adjacent layer is increased, and the total capacitance value between the second electrode 108 of the first metal wire 112 and the first electrode 108 of the second metal wire 111 of the adjacent layer is increased, and the capacitance value of the capacitor density of m is increased.

On the other hand, in the metal wires of the adjacent layers, the comb handle portion 101 of the second metal wire 111 is located right above the comb handle portion 101 of the first metal wire 112, so that the structural symmetry of the multi-layer metal wire 113 in the MOM capacitor is high, the probability of frequency oscillation of the MOM capacitor is reduced, and the performance of the capacitor structure is improved.

In this embodiment, along the normal direction of the surface of the substrate 100, the side walls of the first comb teeth 103 and the side walls of the second comb teeth 106 of the adjacent layers are flush, so that the total effective coupling distance between the first electrode 107 of the first metal wire 112 and the second electrode 108 of the second metal wire 111 of the adjacent layers is reduced, and the total effective coupling distance between the second electrode 108 of the first metal wire 112 and the first electrode 107 of the second metal wire 111 of the adjacent layers is reduced, and accordingly, the total capacitance value between the first electrode 107 of the first metal wire 112 and the second electrode 108 of the second metal wire 111 of the adjacent layers is increased, and the total capacitance value between the second electrode 108 of the first metal wire 112 and the first electrode 107 of the second metal wire 111 of the adjacent layers is increased.

In other embodiments, the side walls of the first comb teeth portions and the second comb teeth portions of the adjacent layers may not be flush, and the projections of the first comb teeth portions and the second comb teeth portions of the adjacent layers on the substrate have partial overlapping areas.

In this embodiment, the number of layers of the first metal line 112 is multiple, and projections of the first metal line 112 on the surface of the substrate 100 are coincident.

It should be noted that, the greater the number of layers of the stacked first metal lines 112, the greater the total capacitance value between the first electrode 107 and the second electrode 108 of the adjacent first metal lines 112, and, at the same time, since the second metal lines 111 are further disposed between the adjacent first metal lines 112, when the number of layers of the first metal lines 112 is multiple, the number of layers of the second metal lines 111 is also multiple, and accordingly, the greater the total capacitance value generated between the first electrode 107 of the first metal line 112 and the second electrode 108 of the second metal line 111 of the adjacent layer is, the greater the total capacitance value generated between the second electrode 108 of the first metal line 112 and the first electrode 107 of the second metal line 111 of the adjacent layer is, thereby increasing the capacitance value of the MOM capacitor.

It should be further noted that the projections of the first metal lines 112 on the surface of the substrate 100 coincide, so that the total coupling area between the first electrode 107 and the second electrode 108 in the adjacent first metal lines 112 is maximized, and correspondingly, the capacitance value generated between the first electrode 107 and the second electrode 108 in the adjacent first metal lines 112 is maximized, thereby improving the capacitance density of the capacitor structure.

In this embodiment, the number of layers of the second metal lines 111 is multiple, and projections of the second metal lines 111 on the surface of the substrate 100 are coincident.

It should be noted that, the greater the number of layers of the stacked second metal lines 111, the greater the total capacitance value between the first electrode 107 and the second electrode 108 of the adjacent second metal lines 111, and, at the same time, since the first metal lines 112 are further disposed between the adjacent second metal lines 111, when the number of layers of the second metal lines 111 is multiple, the number of layers of the first metal lines 112 is also multiple, and accordingly, the greater the total capacitance value generated between the first electrode 107 of the first metal line 112 and the second electrode 108 of the second metal line 111 of the adjacent layer is also the greater the total capacitance value generated between the second electrode 108 of the first metal line 112 and the first electrode 107 of the second metal line 111 of the adjacent layer, thereby increasing the capacitance value of the MOM capacitor.

It should be further noted that the projections of the second metal lines 111 on the surface of the substrate 100 coincide, so that the total coupling area between the first electrode 107 and the second electrode 108 in the adjacent second metal lines 111 is maximized, and correspondingly, the capacitance value generated between the first electrode 107 and the second electrode 108 in the adjacent second metal lines 111 is maximized, thereby improving the capacitance density of the capacitor structure.

In this embodiment, the material of the first metal line 112 includes one or more of aluminum, copper, titanium nitride, tantalum nitride and cobalt.

Specifically, the aluminum, copper, titanium nitride, tantalum nitride and cobalt have lower resistivity, which is favorable for making the resistance value generated by the first metal line 112 lower, so that the performance of the capacitor structure is improved, and meanwhile, the electron mobility of the aluminum, copper, titanium nitride, tantalum nitride and cobalt is faster, the conductivity is higher, and the electrical performance of the capacitor structure can be further improved.

In this embodiment, the material of the second metal line 111 includes one or more of aluminum, copper, titanium nitride, tantalum nitride and cobalt.

Specifically, the aluminum, copper, titanium nitride, tantalum nitride and cobalt have lower resistivity, which is favorable for making the resistance value generated by the first metal line 112 lower, so that the performance of the capacitor structure is improved, and meanwhile, the electron mobility of the aluminum, copper, titanium nitride, tantalum nitride and cobalt is faster, the conductivity is higher, and the electrical performance of the capacitor structure can be further improved.

In this embodiment, in the process of forming the multi-layered metal line 113 on top of the substrate 100, via interconnection structures 116 between the comb handle portions 101 of the metal lines 113 of adjacent layers are also formed, and the via interconnection structures 116 are electrically connected to the comb handle portions 101.

Specifically, the via interconnection structure 116 is configured to electrically connect the stacked layers of the first metal line 112 and the second metal line 111 to each other.

As an example, the first metal line 112 of the lowermost layer is taken as the 1 st layer metal line (M ₁ ) From layer 2 metal lines (M ₂ ) Initially, in the process of forming the first groove (not shown) and the second groove (not shown) corresponding to the n-th layer metal wire, a through hole communicating with the bottom of the comb handle groove is also formed, and the bottom of the through hole exposes the comb handle part 101 in the n-1-th layer metal wire; accordingly, during the formation of the first electrode 107 in the first trench and the formation of the second electrode 108 in the second trench, the material forming the first electrode 107 and the second electrode 108 is also filled in the via hole to form the via interconnection structure 116. Wherein n is an integer greater than or equal to 2. In this embodiment, n=6.

In this embodiment, the material of the via interconnect structure 116 includes one or more of aluminum, copper, titanium nitride, tantalum nitride, and cobalt.

Specifically, aluminum, copper, titanium nitride, cobalt and tantalum nitride have lower resistivity, which is favorable for making the resistance value generated by the via interconnection structure 116 lower, improving the performance of the capacitor structure, and at the same time, aluminum, copper, titanium nitride, cobalt and tantalum nitride have faster electron mobility, have higher conductivity, and can further improve the electrical performance of the capacitor structure.

Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention, and the scope of the invention should be assessed accordingly to that of the appended claims.

Claims (19)

1. A capacitor structure, comprising:

a substrate;

the multi-layer metal wire comprises a first metal wire and a second metal wire which are sequentially and alternately stacked on the substrate and are electrically connected with each other, each layer of metal wire comprises a first electrode and a second electrode, each of the first electrode and the second electrode comprises a comb handle part and a plurality of comb tooth parts which are connected with the comb handle part and are arranged in parallel, the comb tooth part corresponding to the first electrode is used as a first comb tooth part, the comb tooth part corresponding to the second electrode is used as a second comb tooth part, and the second comb tooth part and the first comb tooth part are arranged in a crossing way;

among the metal wires of the adjacent layers, the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the first comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are contacted, and the projections of the second comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are contacted.

2. The capacitor structure of claim 1, characterized in that, in the same layer of the metal wire, first electrodes and second electrodes satisfying the second comb-tooth parts and the first comb-tooth parts are arranged to intersect to form an electrode group;

the number of the electrode groups is multiple, the arrangement direction of the electrode groups is perpendicular to the extending direction of the comb handle part, and adjacent electrode groups share the comb handle part at the junction.

3. The capacitor structure of claim 1, in which, in the metal wires of adjacent layers, the comb handle portion of the second metal wire is located directly above the comb handle portion of the first metal wire.

4. The capacitor structure of claim 1, in which the number of layers of the first metal lines is multiple, and the projections of the first metal lines onto the substrate surface are coincident.

5. The capacitor structure of claim 4, in which the number of layers of the second metal lines is multiple, and the projections of the second metal lines onto the substrate surface are coincident.

6. The capacitor structure of claim 1, in which the capacitor structure further comprises: and the through hole interconnection structure is positioned between the comb handle parts of the metal wires of the adjacent layers and is electrically connected with the comb handle parts.

7. The capacitor structure of any of claim 6, in which the material of the via interconnect structure comprises one or more of aluminum, copper, titanium nitride, tantalum nitride, and cobalt.

8. The capacitor structure of claim 1, in which sidewalls of the first comb-teeth portions of adjacent layers are flush with sidewalls of the second comb-teeth portions along a normal direction of the substrate surface.

9. The capacitor structure of any one of claims 1-8, characterized in that the capacitor structure further comprises: and the metal interlayer dielectric layer is positioned above the substrate at the side parts of the first electrode and the second electrode and covers the side walls of the first electrode and the second electrode.

10. The capacitor structure of any one of claims 1-8, characterized in that the material of the first metal line comprises one or more of aluminum, copper, titanium nitride, tantalum nitride and cobalt;

the material of the second metal line includes one or more of aluminum, copper, titanium nitride, tantalum nitride and cobalt.

11. A method of forming a capacitor structure, comprising:

providing a substrate;

forming a plurality of layers of metal wires on the substrate, wherein the plurality of layers of metal wires comprise a first metal wire and a second metal wire which are sequentially and alternately stacked on the substrate and are electrically connected with each other, each layer of metal wire comprises a first electrode and a second electrode, each of the first electrode and the second electrode comprises a comb handle part and a plurality of comb teeth parts which are connected with the comb handle part and are arranged in parallel, each comb tooth part corresponding to the first electrode is used as a first comb teeth part, each comb tooth part corresponding to the second electrode is used as a second comb teeth part, and each second comb teeth part is arranged in a crossing way with each first comb teeth part;

Among the metal wires of the adjacent layers, the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are arranged in a staggered mode along the arrangement direction of the comb tooth parts, the projections of the first comb tooth parts corresponding to the first metal wires and the first comb tooth parts corresponding to the second metal wires on the substrate are contacted, and the projections of the second comb tooth parts corresponding to the first metal wires and the second comb tooth parts corresponding to the second metal wires on the substrate are contacted.

12. The method of forming a capacitor structure according to claim 11, wherein in the same layer of the metal line, first electrodes and second electrodes satisfying the second comb-teeth portions crossing the first comb-teeth portions form an electrode group;

the number of the electrode groups is multiple, the arrangement direction of the electrode groups is perpendicular to the extending direction of the comb handle part, and adjacent electrode groups share the comb handle part at the junction.

13. The method of forming a capacitor structure of claim 11, wherein in the metal lines of adjacent layers, the comb handle portion of the second metal line is located directly above the comb handle portion of the first metal line.

14. The method of forming a capacitor structure of claim 11, wherein a plurality of metal patterning processes are performed to form said multi-layered metal lines, said metal patterning processes being used to form said metal lines of a same layer, said metal patterning processes comprising: forming a metal interlayer dielectric layer on the top of the substrate;

forming a comb-shaped first groove and a comb-shaped second groove which penetrate through the metal interlayer dielectric layer, wherein the first groove and the second groove both comprise comb handle grooves and comb tooth grooves which are communicated with the comb handle grooves and are arranged in parallel, the comb tooth groove corresponding to the first groove is used as a first comb tooth groove, the comb tooth groove corresponding to the second groove is used as a second comb tooth groove, and the second comb tooth groove is arranged in an intersecting manner with the first comb tooth groove;

filling metal materials in the first groove and the second groove to form a comb handle part positioned in the comb handle groove and a comb tooth part positioned in the comb tooth groove, wherein the comb handle part and the comb tooth part in the first groove form a first electrode, and the comb handle part and the comb tooth part in the second groove form a second electrode;

The comb tooth grooves formed in the metal patterning process at the next time are arranged in a staggered mode along the arrangement direction of the comb tooth grooves and the comb tooth parts formed in the metal patterning process at the previous time, and the projection of the comb tooth grooves on the substrate is contacted with the projection of the comb tooth parts on the substrate.

15. The method of forming a capacitor structure of claim 14, wherein the process of forming a first electrode in the first trench and the process of forming a second electrode in the second trench each comprise an electrochemical plating process.

16. The method of forming a capacitor structure of claim 11, wherein during the formation of the multi-layered metal lines on top of the substrate, via interconnection structures between comb handles of adjacent layers of the metal lines are also formed and electrically connected to the comb handles.

17. The method of forming a capacitor structure of claim 11, wherein the number of layers of the first metal lines is multiple, and projections of the first metal lines on the substrate surface are coincident.

18. The method of forming a capacitor structure of claim 17, wherein the number of layers of said second metal lines is multiple, and projections of said second metal lines onto said substrate surface are coincident.

19. The method of forming a capacitor structure of claim 11, wherein sidewalls of the first comb-teeth portions of adjacent layers are flush with sidewalls of the second comb-teeth portions along a normal direction of the substrate surface.