Abstract:
Metal-insulator-metal capacitors include a first capacitor electrode comprising a first metal extending on a substrate and a first electrically insulating layer comprising a first material extending on the first capacitor electrode. The first electrically insulating layer has a first opening therein that exposes a first portion of the first capacitor electrode. An electrically insulating etch-stop layer that comprises a second material different from the first material, extends on the first electrically insulating layer and has a second opening therein. A capacitor dielectric layer extends on the exposed first portion of the first capacitor electrode and on sidewalls of the first electrically insulating layer and the etch-stop layer. A second capacitor electrode that comprises a second metal extends on the capacitor dielectric layer and opposite the first capacitor electrode. The first and second metals may both comprise copper, gold or aluminum. The second capacitor electrode may also comprise a composite of a tungsten plug and another metal layer on the tungsten plug.

Description:
RELATED APPLICATION 
     This application is related to Korean Application No. 99-3786, filed Feb. 4, 1999, the disclosure of which is hereby incorporated herein by reference. 
     FIELD OF THE INVENTION 
     This invention relates to integrated circuit devices and methods of forming integrated circuit devices and, more particularly, to integrated circuit capacitors and methods of forming integrated circuit capacitors. 
     BACKGROUND OF THE INVENTION 
     Integrated circuit devices frequently utilize on-chip capacitors as charge storage devices. Such integrated circuit devices may include memory devices having data storage capacitors therein. For example, in a dynamic random access memory (DRAM) device, each memory cell typically includes a respective storage capacitor. In these types of memory devices, the amount of charge held by each storage capacitor is a function of the value of the data written into the respective memory cell. To reliably store and read data from a memory cell, it is important that the C-V characteristics of each storage capacitor not vary significantly as a function of temperature and/or voltage applied across the capacitor. 
     One conventional method of forming an integrated circuit capacitor is illustrated by FIGS. 1 and 2 a - 2   d . In particular, FIG. 2 a  illustrates the steps of forming a polysilicon layer  12  on a semiconductor substrate  10  and field oxide layer (not shown). A buffer oxide layer  14   a  is also formed on the polysilicon layer  12 . The conductivity of the polysilicon layer  12  may then be increased by implanting dopants  15  through the buffer oxide layer  14   a  and into the polysilicon layer  12 . These dopants may comprise N-type dopants selected from the group consisting of arsenic (As) and phosphorus (P). A silicon nitride layer  14   b  is then deposited on the buffer oxide layer  14   a . A layer of photoresist (not shown) is then formed on the silicon nitride layer  14   b  and patterned using conventional techniques. As illustrated by FIG. 2 b , a selective etching step is then performed by etching through the silicon nitride layer  14   b , the buffer oxide layer  14   a  and the polysilicon layer  12  to expose the semiconductor substrate  10 . The resulting structure includes a polysilicon pattern  12   a  having an insulating capping layer  14  thereon. 
     Referring now to FIG. 2 c , a thermal oxidation step is performed to form thermal gate oxide layer  16 . Because silicon nitride is resistant to oxidation, the gate oxide layer  16  selectively forms on the surface of the substrate  10  and on the sidewalls of the polysilicon pattern  12   a , but not on an upper surface of the silicon nitride layer  14   b . A blanket layer of polycide  18  is then deposited on the substrate  10  and on the polysilicon pattern  12   a , as illustrated. 
     Referring now to FIG. 2 d , a layer of photoresist (not shown) is the formed on the blanket layer of polycide  18  and patterned using conventional techniques. A selective etching step is then performed on the blanket layer of polycide  18  and the gate oxide layer  16 , to define a poly-insulator-poly (PIP) capacitor, having an polycide upper capacitor electrode  18   a , and define a gate electrode  18   b . As illustrated by FIGS. 1 and 2 d , the area of the upper capacitor electrode  18   a  may be smaller than the area of the lower capacitor electrode  12   a.    
     Unfortunately, the C-V characteristics of PIP capacitors, including those formed in accordance with the method of FIGS. 1 and 2 a - 2   d , may experience significant dependence on temperature and voltage. For example, typical voltage coefficients of capacitance (VCC) and temperature coefficients of capacitance (TCC) are 200 ppm/N (part per million per volt) and 120 ppm/° C. respectively. Moreover, because PIP capacitors may comprise electrodes having relatively high resistivity, PIP capacitors may not have acceptable high frequency switching characteristics. These limitations associated with the C-V and resistance characteristics of PIP capacitors may limit the performance of integrated circuit devices (analog and digital) that utilize PIP capacitors. Thus, notwithstanding conventional techniques to form integrated circuit capacitors having polysilicon based electrodes, there continues to be a need for improved integrated circuit capacitors and methods of forming integrated circuit capacitors. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide improved integrated circuit capacitors and methods of forming same. 
     It is another object of the present invention to provide integrated circuit capacitors having excellent VCC and TCC characteristics and methods of forming same. 
     It is still another object of the present invention to provide integrated circuit capacitors having improved reliability and excellent high frequency characteristics and methods of forming same. 
     These and other objects, advantages and features of the present invention are provided by integrated circuit capacitors having a preferred metal-insulator-metal (MIM) structure and methods of forming same. The preferred methods include the use of copper damascene processing techniques. The use of these techniques improve the VCC and TCC characteristics of the capacitors relative to conventional PIP type capacitors. In particular, integrated circuit capacitors of the present invention include a first capacitor electrode comprising a first metal extending on a substrate and a first electrically insulating layer comprising a first material extending on the first capacitor electrode. The first electrically insulating layer has a first opening therein that exposes a first portion of the first capacitor electrode. An electrically insulating etch-stop layer that comprises a second material different from the first material, extends on the first electrically insulating layer and has a second opening therein. A capacitor dielectric layer extends on the exposed first portion of the first capacitor electrode and on sidewalls of the first electrically insulating layer and the etch-stop layer. A second capacitor electrode that comprises a second metal extends on the capacitor dielectric layer and opposite the first capacitor electrode. Accordingly, a MIM capacitor comprising a first capacitor electrode, capacitor dielectric layer and second capacitor electrode is formed. 
     According to a preferred aspect of the present invention, the capacitor dielectric layer comprises a material selected from the group consisting of plasma-enhance tetraethylorthosilicate (PE-TEOS), plasma-enhanced oxide (PEOX), plasma-enhanced silicon nitride (PESiN), silicon oxynitride (SiON), high density plasma (HDP), tantalum pentoxide (Ta 2 O 5 ), spin-on glass (SOG), O 3 -TEOS and BST (BaSrTiO 3 ). The first and second metals also preferably comprise copper or gold. Alternatively, the first or second metal may comprise aluminum. A preferred embodiment of the present invention may also include the use of a tungsten (W) plug that extends between the capacitor dielectric layer and the second capacitor electrode. The insulating etch-stop layer may also comprise silicon oxynitride (SiON). 
     Preferred methods of forming integrated circuit capacitors also comprise the steps of forming a first capacitor electrode comprising a first metal on a substrate and then forming a first interlayer insulating layer comprising a first electrically insulating material, on the first capacitor electrode. An etch-stop layer comprising a second electrically insulating material different from the first electrically insulating material, is also formed on the first interlayer insulating layer. A contact hole is then formed that extends through the etch-stop layer and the first interlayer insulating layer and exposes a portion of the first capacitor electrode. Next, a capacitor dielectric layer is formed on the exposed portion of the first capacitor electrode and on sidewalls of the first interlayer insulating layer and the etch-stop layer. The MIM capacitor structure may then be completed by forming second capacitor electrode comprising a second metal on the capacitor dielectric layer. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIGS. 1 and 2 a - 2   d  are cross-sectional views of intermediate structures that illustrate a conventional method of forming an integrated circuit capacitor. 
     FIGS. 3 and 4 a - 4   e  are cross-sectional views of intermediate structures that illustrate methods of forming integrated circuit capacitors according to a first embodiment of the present invention. 
     FIGS. 5 a - 5   e  are cross-sectional views of intermediate structures that illustrate methods of forming integrated circuit capacitors according to a second embodiment of the present invention. 
     FIGS. 6 and 7 a - 7   d  are cross-sectional views of intermediate structures that illustrate methods of forming integrated circuit capacitors according to a third embodiment of the present invention. 
     FIGS. 8 and 9 a - 9   d  are cross-sectional views of intermediate structures that illustrate methods of forming integrated circuit capacitors according to a fourth embodiment of the present invention. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the thickness of layers and regions are exaggerated for clarity. It will also be understood that when a layer is referred to as being “on” another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Like numbers refer to like elements throughout. 
     Referring now to FIGS. 3 and 4 a - 4   e , preferred methods of forming an integrated circuit capacitor according to a first embodiment of the present invention will be described. In particular, FIG. 4 a  illustrates the steps of forming a first interlayer insulating layer  102  on a semiconductor substrate  100 . The first interlayer insulating layer  102  may comprise silicon dioxide. A first etch-stop layer  104  and second interlayer insulating layer  106  are then formed in sequence on the first interlayer insulating layer  102 . The first etch-stop layer  104  may comprise an electrically insulating material such as silicon nitride (SiN) or silicon oxynitride (SiON). 
     A layer of photoresist (not shown) is then formed on an upper surface of the second interlayer insulating layer  106 . This layer of photoresist is then patterned using conventional techniques. The patterned layer of photoresist is then used as an etching mask during the step of selectively etching the second interlayer insulating layer  106 . This selective etching step is performed until the underlying first etch-stop layer  104  is exposed. Another selective etching step is then performed to define a first contact hole hi that extends through the first etch-stop layer  104  and the first interlayer insulating layer  102  and exposes the underlying substrate  100 . The first contact hole hi also exposes sidewalls of the first etch-stop layer  104  and the first interlayer insulating layer  102 . Referring now to FIG. 4 b , a first blanket metal layer is then conformally deposited onto the second interlayer insulating layer  106  and into the first contact hole h 1 . This blanket metal layer may comprise copper (Cu) or gold (Au), for example. A planarization step is then performed to define a first wiring line  108   a  and a lower capacitor electrode  108   b . This planarization step may be performed using conventional chemical-mechanical polishing (CMP) techniques. 
     Referring now to FIG. 4 c , a third interlayer insulating layer  110  is deposited on the structure of FIG. 4 b . A second etch-stop layer  112  and a fourth interlayer insulating layer  114  are then deposited in sequence on the third interlayer insulating layer  110 . Like the first etch-stop layer  104 , the second etch-stop layer  112  may comprise silicon nitride or silicon oxynitride, for example. A layer of photoresist (not shown) is then formed on an upper surface of the fourth interlayer insulating layer  114 . This layer of photoresist may then be patterned using conventional exposure and developing techniques. The patterned layer of photoresist can then be used as an etching mask during the step of selectively etching the fourth interlayer insulating layer  114  to expose portions of the second etch-stop layer  112 . 
     Referring now to FIG. 4 d , another selective etching step is then performed to define a second contact hole h 2 . The second contact hole h 2  extends through the second etch-stop layer  112  and the third interlayer insulating layer  110  and exposes the lower capacitor electrode  108   b , as illustrated. A layer  116  of dielectric material is then conformally deposited onto the fourth interlayer insulating layer  114  and into the second contact hole h 2 . This deposition step may be performed using a chemical vapor deposition (CVD) technique. The dielectric material may comprise plasma-enhance tetra-ethyl-ortho-silicate (PE-TEOS), plasma-enhanced oxide (PEOX), plasma-enhanced silicon nitride (PESiN), silicon oxynitride (SiON), high density plasma (HDP), tantalum pentoxide (Ta 2 O 5 ), spin-on glass (SOG), O 3 -TEOS and BST (BaSrTiO 3 ), for example. After deposition of the layer  116  of dielectric material, an additional selective etching step is performed using an patterned photoresist layer (not shown) as an etching mask. During this etching step, the layer  116  of dielectric material, the second etch-stop layer  112  and the third interlayer insulating layer  110  are etched in sequence to define a third contact hole h 3  that exposes a portion of an upper surface of the first wiring line  108   a.    
     Referring now to FIGS. 3 and 4 e , a second blanket metal layer is then conformally deposited onto the layer  116  of dielectric material and into the second and third contact holes h 2  and h 3 . This second blanket metal layer may also comprise copper (Cu) or gold (Au), for example. The second blanket metal layer may then be planarized to define a second wiring line  118   a  (that ohmically contacts the first wiring line  108   a ) and an upper capacitor electrode  118   a . Accordingly, a metal-insulator-metal (MIM) type capacitor can be formed in accordance with the methods illustrated by FIGS. 3 and 4 a - 4   e . Moreover, the lower and upper electrodes of the MIM capacitor can be formed of copper using copper damascene processes. According to another aspect of this embodiment of the present invention, electrically insulating capping layers (not shown) may be formed at intermediate stages of processing. For example, a first capping layer may be formed on the first wiring line  108   a  and on the lower capacitor electrode  108   b  after the steps illustrated by FIG. 4 b  have been performed. The first capping layer may comprise silicon oxynitride (SiON) and may act as a protective layer in the event subsequently formed contact holes are misaligned during processing. A second capping layer may also be formed (as a protection layer) on the second wiring line  118   a  and on the upper capacitor electrode  118   b , after the steps illustrated by FIG. 4 e  have been performed. These capping layers may also be selectively etched during processing to expose underlying structures. In addition, barrier metal layers (not shown) may be deposited into the first and third contact holes hi and h 3  prior to formation of the first wiring line  108   a  and the second wiring line  118   a , respectively. These barrier metal layers may be used to improve (e.g., lower) contact resistance. The barrier metal layers may comprise a material selected from the group consisting of Ti, Ta, W, Mo, TiN, TiW, TaN, MoN, W—N, W—Si—N, Ta—Si—N, W—B—N and Ti—Si—N. 
     Referring to FIGS. 5 a - 5   e , preferred methods of forming an integrated circuit capacitor according to a second embodiment of the present invention will be described. In particular, FIG. 5 a  illustrates the steps of forming a first interlayer insulating layer  102  on a semiconductor substrate  100 . The first interlayer insulating layer  102  may comprise silicon dioxide. Using a conventional photolithographically defined etching mask, a first contact hole hi may be formed in the first interlayer insulating layer  102 . This first contact hole is then filled with a conductive plug  103  comprising a material such as tungsten (W). This step may be performed by depositing a blanket layer of tungsten and then planarizing the blanket layer until an upper surface of the first interlayer insulating layer  102  is exposed. 
     Referring now to FIG. 5 b , a first etch-stop layer  104  and a second interlayer insulating layer  106  are then formed in sequence on the first interlayer insulating layer  102 . The first etch-stop layer  104  may comprise an electrically insulating material such as silicon nitride (SiN) or silicon oxynitride (SiON). A layer of photoresist (not shown) may then be formed on an upper surface of the second interlayer insulating layer  106 . This layer of photoresist is then patterned using conventional techniques. The patterned layer of photoresist is then used as an etching mask during the step of selectively etching the second interlayer insulating layer  106 . This selective etching step is performed until the first interlayer insulating layer  102  is exposed and the conductive plug  103  is exposed, as illustrated. A first blanket metal layer is then conformally deposited onto the second interlayer insulating layer  106  and onto the exposed portions of the first interlayer insulating layer  102  and onto the conductive plug  103  to form an ohmic contact therewith. This blanket metal layer may comprise copper (Cu) or gold (Au), for example. A conventional metallization technique is then performed on the blanket metal layer to define a first wiring line  109   a  and a lower capacitor electrode  109   b.    
     Referring now to FIG. 5 c , a third interlayer insulating layer  110  is deposited on the structure of FIG. 5 b . A second etch-stop layer  112  and fourth interlayer insulating layer  114  are then deposited in sequence on the third interlayer insulating layer  110 . Like the first etch-stop layer  104 , the second etch-stop layer  112  may comprise silicon nitride or silicon oxynitride, for example. A layer of photoresist (not shown) may then be formed on an upper surface of the fourth interlayer insulating layer  114 . This layer of photoresist is then patterned using conventional techniques. The patterned layer of photoresist is then used as an etching mask during the step of selectively etching the fourth interlayer insulating layer  114  to expose selected portions of the second etch-stop layer  112 . 
     Referring now to FIG. 5 d , another selective etching step is then performed to define a second contact hole h 2 . The second contact hole h 2  extends through the second etch-stop layer  112  and through the third interlayer insulating layer  110  and exposes a portion of the lower capacitor electrode  109   b , as illustrated. A layer  116  of dielectric material is then conformally deposited onto the fourth interlayer insulating layer  114  and into the second contact hole h 2 . This deposition step may be performed using a chemical vapor deposition (CVD) technique. The dielectric material may comprise plasma-enhance tetra-ethyl-ortho-silicate (PE-TEOS), plasma-enhanced oxide (PEOX), plasma-enhanced silicon nitride (PESiN), silicon oxynitride (SiON), high density plasma (HDP), tantalum pentoxide (Ta 2 O 5 ), spin-on glass (SOG), O 3 -TEOS and BST (BaSrTiO 3 ), for example. After deposition of the layer  116  of dielectric material, an additional selective etching step is performed using an patterned photoresist layer (not shown) as an etching mask. During this etching step, the layer  116  of dielectric material, the second etch-stop layer  112  and the third interlayer insulating layer  110  are etched in sequence to define a third contact hole h 3  that exposes a portion of an upper surface of the first wiring line  109   a.    
     Referring now to FIG. 5 e , a second blanket metal layer is then conformally deposited onto the layer  116  of dielectric material and into the second and third contact holes h 2  and h 3 . This second blanket metal layer may also comprise copper (Cu) or gold (Au), for example. The second blanket metal layer may then be planarized to define a second wiring line  118   a  (that ohmically contacts the first wiring line  109   a ) and an upper capacitor electrode  118   a . Accordingly, a metal-insulator-metal (MIM) type capacitor can be formed in accordance with the methods illustrated by FIGS. 5 a - 5   e . Like the first embodiment, electrically insulating capping layers and barrier metal layers may be formed during intermediate stages of processing. 
     Referring now to FIGS. 6 and 7 a - 7   d , preferred methods of forming an integrated circuit capacitor according to a third embodiment of the present invention will be described. In particular, FIG. 7 a  illustrates the steps of forming a first interlayer insulating layer  202  on a semiconductor substrate  200 . The first interlayer insulating layer  202  may comprise silicon dioxide. As described above with respect to the second embodiment of the present invention, the first interlayer insulating layer  202  is then selectively etched to define a contact hole therein. This contact hole is then filled with a conductive plug comprising a material such as tungsten (W). Prior to formation of the conductive plug  204 , a barrier metal layer (not shown) may be deposited into a bottom of the contact hole to lower the contact resistance between the conductive plug  204  and the substrate  200 . 
     A first wiring line  206   a  and a lower capacitor electrode  206   b  are then formed on the first interlayer insulating layer  202 , as illustrated. The first wiring line  206   a  ohmically contacts the conductive plug  204 . The first wiring line  206   a  and the lower capacitor electrode  206   b  may be formed by depositing a conductive layer comprising aluminum (Al), for example, and then patterning the deposited conductive layer by selectively etching the deposited layer using a patterned photoresist mask (not shown). Other metal patterning techniques may also be used. This etching step may be preceded by the step of forming a capping layer (e.g., SiON capping layer), as described above, on the deposited conductive layer or on the patterned regions defined therefrom. As illustrated, the first wiring line  206   a  electrically contacts the conductive plug  204 . 
     Referring now to FIG. 7 b , a second interlayer insulating layer  208  is then deposited onto the first interlayer insulating layer  202  and onto the first wiring line  206   a  and onto the lower capacitor electrode  206   b , as illustrated. An etch-stop layer  210  and a third interlayer insulating layer  212  are then deposited in sequence on the second interlayer insulating layer  208 . The third interlayer insulating layer  212  is then patterned using conventional techniques, to expose selected underlying portions of the etch-stop layer  210 . 
     Referring now to FIG. 7 c , another selective etching step is then performed on the structure of FIG. 7 b  to define a second contact hole h 2 . The second contact hole h 2  extends through the second etch-stop layer  210  and the third interlayer insulating layer  208  and exposes the lower capacitor electrode  206   b . A layer  214  of dielectric material is then conformally deposited onto the fourth interlayer insulating layer  212  and into the second contact hole h 2 . This deposition step may be performed using a chemical vapor deposition (CVD) technique. The dielectric material may comprise plasma-enhance tetra-ethyl-ortho-silicate (PE-TEOS), plasma-enhanced oxide (PEOX), plasma-enhanced silicon nitride (PESiN), silicon oxynitride (SiON), high density plasma (HDP), tantalum pentoxide (Ta 2 O 5 ), spin-on glass (SOG), O 3 -TEOS and BST (BaSrTiO 3 ), for example. After deposition of the layer  214  of dielectric material, an additional selective etching step is performed using an patterned photoresist layer (not shown) as an etching mask. During this etching step, the layer  214  of dielectric material, the second etch-stop layer  210  and the third interlayer insulating layer  208  are etched in sequence to define a third contact hole h 3  that exposes a portion of an upper surface of the first wiring line  206   a.    
     Referring now to FIGS. 6 and 7 d , a second blanket metal layer is then conformally deposited onto the layer  214  of dielectric material and into the second and third contact holes h 2  and h 3 . This second blanket metal layer may also comprise copper (Cu) or gold (Au), for example. The second blanket metal layer may then be planarized to define a second wiring line  216   a  (that ohmically contacts the first wiring line  206   a ) and an upper capacitor electrode  216   b . Accordingly, a metal-insulator-metal (MIM) type capacitor can be formed in accordance with the methods illustrated by FIGS. 6 and 7 a - 7   d . A capping layer (not shown) may also be formed (as a protection layer) on the second wiring line  216   a  and on the upper capacitor electrode  216   b , after the steps illustrated by FIG. 7 d  have been performed. 
     Referring now to FIGS. 8 and 9 a - 9   d , preferred methods of forming integrated circuit capacitors according to a fourth embodiment of the present invention will be described. In particular, FIG. 9 a  illustrates the steps of forming a first interlayer insulating layer  302  on a semiconductor substrate  300 . A first etch-stop layer  304  and a second interlayer insulating layer  306  are then formed in sequence on the first interlayer insulating layer  302 . A step is then performed to selectively etch the second interlayer insulating layer  306  until portions of the first etch-stop layer  304  are exposed, using a photoresist mask (not shown) as an etching mask. Following this etching step, another selective etching step is performed to define a first contact hole hi by etching through the first etch-stop layer  304  and through the first interlayer insulating layer  302  and exposing the underlying substrate  300 . 
     Referring now to FIG. 9 b , a first wiring line  308   a  and a lower capacitor electrode  308   b  are then formed by conformally depositing a blanket metal layer on the structure of FIG. 9 a  and then planarizing the deposited layer using the second interlayer insulating layer  306  as a planarization stop layer. Referring now to FIG. 9 c , a third interlayer insulating layer  310  is then formed on the structure of FIG. 9 b . The third interlayer insulating layer  310  is then patterned to define a second contact hole h 2  therein that exposes the lower capacitor electrode  308   a . A layer of dielectric material  312  is then conformally deposited onto the third interlayer insulating layer  310  and into the second contact hole h 2 . A selective etching step is then performed to etch through the layer of dielectric material  312  and the third interlayer insulating layer  310  in sequence to define a third contact hole h 3  that exposes the first wiring line  308   a.    
     As illustrated by FIGS. 8 and 9 d , a blanket layer of a conductive material such as tungsten (W) is then conformally deposited on the structure of FIG. 9 c . A planarization or etch-back step is then performed on the blanket layer of conductive material, using the third interlayer insulating layer  310  as a planarization or etch stop layer. This planarization step results in the formation of first and second conductive plugs  314   a  and  314   b , respectively. Another blanket layer of conductive material such as aluminum (Al) is then deposited on the third interlayer insulating layer  310  and on the first and second conductive plugs  314   a and  314   b . This blanket layer of conductive material is then patterned to define a second wiring line  316   a  and an upper capacitor electrode. The upper capacitor electrode comprises the conductive pattern  316   b  in combination with the second conductive plug  314   b . Thus, according to this embodiment, only one copper demascene process is required when forming the first wiring line  308   a  and lower capacitor electrode  308   a . Like the first, second and third embodiments, additional capping layers (not shown) and barrier metal layers (not shown) may be formed at intermediate processing steps. 
     According to preferred aspects of the present invention, the use of copper damascene processing techniques during formation of MIM integrated circuit capacitors improves the electrical characteristics of capacitors. For example, when compared to conventional methods of forming PIP capacitors, the value of VCC for MIM capacitors formed in accordance with the present invention can be achieved at levels in a range between about 0.166 and 0.2 times the value of VCC for conventional PIP capacitors. Also, the value of TCC for MIM capacitors formed in accordance with the present invention can be achieved at levels below about 0.5 times the value of TCC for conventional PIP capacitors. Thus, MIM capacitors according to the present invention can be expected to have improved C-V characteristics (lower voltage and temperature dependence and improved high frequency performance). These improvements can also be expected to improve the bit resolution characteristics of memory cells that utilize these MIM capacitors (relative to PIP type capacitors). 
     In the drawings and specification, there have been disclosed typical preferred embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.