1. Field of the Invention
This invention relates in general to thin-film capacitors and more specifically to a thin-film capacitor with a field modification layer and methods for forming the same.
2. Description of the Related Art
Thin-film capacitors increasingly have thinner insulator and electrode layers. Thinning of the insulator layer, however, poses several problems in such capacitors. In particular, enhanced electric field at the corners of the electrode layers can generate higher leakage current at the periphery of the thin-film capacitors. In certain instances, leakage current can be large enough to cause insulator breakdown at the electrode layer edges. Insulator breakdown is more likely to happen in thin-film capacitors with thinner insulator layers. Susceptibility to insulator breakdowns lowers the reliability of thin-film capacitors.
Thus, there is a need for improved thin-film capacitors and methods for forming the same.
The present invention may be better understood, and its numerous objects, features, and advantages made apparent to those skilled in the art by referencing the accompanying drawings.
Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve the understanding of the embodiments of the present invention.
The following sets forth a detailed description of a mode for carrying out the invention. The description is intended to be illustrative of the invention and should not be taken to be limiting.
In one aspect, a method for forming a capacitor, such as a thin-film capacitor, is provided. The method may include providing a metal-containing bottom electrode and forming a capacitor insulator over the metal-containing bottom electrode. The method may further include forming a metal-containing top electrode layer over the capacitor insulator. The method may further include forming a dielectric-containing field modification layer over the capacitor insulator and at least partially surrounding the metal-containing top-electrode.
In another aspect, a method for forming a capacitor, such as a thin-film capacitor is provided. The method may include providing a bottom electrode and forming a capacitor insulator over the bottom electrode. The method may further include forming a metal-containing top electrode over the capacitor insulator. The method may further include oxidizing a sidewall region of the metal-containing top electrode to form an oxide-containing field modification layer at least partially surrounding the metal-containing top electrode.
In yet another aspect, a capacitor comprising a metal-containing bottom electrode and a capacitor insulator over the metal-containing bottom electrode is provided. The capacitor may further include a metal-containing top electrode over the capacitor insulator. The capacitor may further include a dielectric-containing field modification layer over the capacitor insulator and at least partially surrounding the metal-containing top electrode.
As shown in
In the foregoing specification, the invention has been described with reference to specific embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present invention.
Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or element of any or all the claims. As used herein, the terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
This is a divisional application of and claims priority under 35 U.S.C. §120 to U.S. patent application Ser. No. 11/326,524 entitled “Thin-Film Capacitor with a Field Modification Layer and Methods for Forming the Same,” by Roberts et al., filed Jan. 4, 2006, which is assigned to the current assignee hereof and incorporated herein by reference in its entirety.
Number | Name | Date | Kind |
---|---|---|---|
5504041 | Summerfelt | Apr 1996 | A |
5554564 | Nishioka et al. | Sep 1996 | A |
5619393 | Summerfelt et al. | Apr 1997 | A |
5686151 | Imai et al. | Nov 1997 | A |
6025257 | Jeon | Feb 2000 | A |
6144060 | Park et al. | Nov 2000 | A |
6184551 | Lee et al. | Feb 2001 | B1 |
6215646 | Ochiai et al. | Apr 2001 | B1 |
6261849 | Lee | Jul 2001 | B1 |
6344964 | Adler | Feb 2002 | B1 |
6379977 | Sun et al. | Apr 2002 | B1 |
6414344 | Kweon | Jul 2002 | B1 |
6614643 | Morita et al. | Sep 2003 | B1 |
6670256 | Yang et al. | Dec 2003 | B2 |
6825081 | Zheng | Nov 2004 | B2 |
6831319 | Zheng | Dec 2004 | B2 |
6897105 | Wilk et al. | May 2005 | B1 |
6898068 | Rost et al. | May 2005 | B2 |
6927121 | Oh et al. | Aug 2005 | B2 |
20030096473 | Shih et al. | May 2003 | A1 |
20030211687 | Lee | Nov 2003 | A1 |
Number | Date | Country |
---|---|---|
2000022083 | Jan 2000 | JP |
Number | Date | Country | |
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20090279226 A1 | Nov 2009 | US |
Number | Date | Country | |
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Parent | 11326524 | Jan 2006 | US |
Child | 12431288 | US |