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Active area bonding compatible high current structuresRelated Patent Categories: Active Solid-state Devices (e.g., Transistors, Solid-state Diodes), Combined With Electrical Contact Or Lead, Ball Or Nail Head Type Contact, Lead, Or BondActive area bonding compatible high current structures description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20070187837, Active area bonding compatible high current structures. Brief Patent Description - Full Patent Description - Patent Application Claims
[0001] This application is a continuation of prior U.S. patent application No. 11/305,987, filed Dec. 19, 2005 (currently pending), which is a divisional of prior U.S. patent application No. 10/698,184, filed Oct. 31, 2003, now U.S. Pat. No. 7,005,369, which claims the benefit under 35 U.S.C. .sctn.119(e) of U.S. Provisional Application Ser. No. 60/496,881, filed Aug. 21, 2003, and U.S. Provisional Application Ser. No. 60/507,539, filed Sep. 30, 2003, all of which are incorporated herein by reference in their entirety. TECHNICAL FIELD [0002] The present invention relates generally to the formation of semiconductor devices and in particular a formation of active circuits under a bond pad. BACKGROUND [0003] Integrated circuits comprise two or more electronic devices formed in and/or on a substrate of semi-conductive material. Typically, the integrated circuits include two or more metal layers that are used in forming select devices and interconnects between said devices. The metal layers also provide electrical paths to input and output connections of the integrated circuit. Connections to the inputs and outputs of the integrated circuit are made through bond pads. Bond pads are formed on a top metal layer of the integrated circuit. A bonding process (i.e. the bonding of a ball bond wire to the bond pad) can damage any active circuitry formed under the metal layer upon which the bonding pad is formed. Therefore, present circuit layout rules either do not allow any circuitry to be formed under the bonding pad or only allow limited structures that have to be carefully tested. [0004] Damage under bonding pads can be caused by many reasons but mainly it is due to the stresses which have occurred during bond wire attachment process and the subsequent stresses after packaging. For example, temperature excursions after packaging exert both lateral and vertical forces on the overall structure. The metal layers of integrated circuit are typically made of soft aluminum that are separated from each other by harder oxide layers. The soft aluminum tends to give under the forces while the harder oxide layers do not. This eventually leads to cracks in the oxide layers. Once an oxide layer cracks, moisture can enter causing corrosion of the aluminum layers and eventually failure of the circuit function. Therefore, the bonding process typically requires the real estate below the bond pad serve only as a buffer against damage that occurs during the bonding process. However, as chip designers try and reduce the size of chips it would be desired to able to use the real estate under the bonding pad for active circuits or interconnects. [0005] For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for an improved integrated circuit that effectively allows for use of the real estate under bonding pads for active circuits and interconnects. SUMMARY [0006] The above-mentioned problems of current systems are addressed by embodiments of the present invention and will be understood by reading and studying the following specification. The following summary is made by way of example and not by way of limitation. It is merely provided to aid the reader in understanding some of the aspects of the invention. [0007] In one embodiment, a semiconductor structure is provided. The structure comprises at least one active device located in a substrate and directly under a bond pad. A conductor is located between the bond pad and the substrate. The conductor has a plurality of gaps filled with insulating material. The insulating material is harder than the conductor. BRIEF DESCRIPTION OF THE DRAWINGS [0008] The present invention can be more easily understood and further advantages and uses thereof more readily apparent, when considered in view of the description of the preferred embodiments and the following figures in which: [0009] FIG. 1 is a partial cross-sectional view of an integrated circuit of one embodiment of the present invention; [0010] FIG. 2 is a top view of a portion of a metal layer with gaps of one embodiment of the present invention; and [0011] FIGS. 3A through 3G are partial cross-sectional side views of one method of forming an integrated circuit in one embodiment of the present invention. [0012] In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the present invention. Reference characters denote like elements throughout Figures and text. DETAILED DESCRIPTION [0013] In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific preferred embodiments in which the inventions may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical and electrical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims and equivalents thereof. [0014] In the following description, the term substrate is used to refer generally to any structure on which integrated circuits are formed, and also to such structures during various stages of integrated circuit fabrication. This term includes doped and undoped semiconductors, epitaxial layers of a semiconductor on a supporting semiconductor or insulating material, combinations of such layers, as well as other such structures that are known in the art. Terms of relative position as used in this application are defined based on a plane parallel to the conventional plane or working surface of a wafer or substrate, regardless of the orientation of the wafer or substrate. The term "horizontal plane" or "lateral plane" as used in this application is defined as a plane parallel to the conventional plane or working surface of a wafer or substrate, regardless of the orientation of the wafer or substrate. The term "vertical" refers to a direction perpendicular to the horizontal. Terms, such as "on", "side" (as in "sidewall"), "higher", "lower", "over," "top" and "under" are defined with respect to the conventional plane or working surface being on the top surface of the wafer or substrate, regardless of the orientation of the wafer or substrate. [0015] Embodiments of the present invention provide a method and structure of an integrate circuit that allows the use of real estate under bonding pads for active devices and interconnects. Moreover, embodiments of the present invention provide a structure that can use all the metal layers below the bond pad for functional interconnections of the device. In addition, embodiments of the present invention also provide a structure that allows submicron interconnects lines with a TiN top layer and relatively wide lines capable of carrying high currents to exist simultaneously under a bond pad. [0016] FIG. 1 illustrates a partial cross-section view of an integrated circuit 100 of one embodiment of the present invention. In this embodiment, the part of the integrated circuit 100 shown includes a N-channel MOS power device 102, a N-DMOS device 104 and a NPN bipolar device 106. As FIG. 1 also illustrates three conductive layers, which in this embodiment includes a first metal layer M1 108, a second metal layer M2 110 and a third metal layer M3 112. The metal layers 108, 110, and 112 can be made of conductive material such as aluminum, copper and the like. Moreover, in another embodiment, at least one of the metal layers 108, 110 and 112 is made by a sub-micron process that forms many sub-layers of alternating conductive layers. The third metal layer M3 112 can be referred to as the top metal layer 112. As illustrated, a bond pad 130 is formed on a surface of the third metal layer M3 112 by patterning a passivation layer 132. A ball bond wire 114 (bond wire 114) can be coupled to the bonding pad 130 to provide an input or output to the integrated circuit 100. Although, this embodiment, only illustrates three metal layers 108, 110 and 112, other embodiments have more or less metal layers. For example, in an embodiment with more than three metal layers, additional metal layers are formed between metal layers 108 and 110. Each interconnect metal layer 108, 110 and 112 is formed by conventional methods known in the art such as depositing and patterning. [0017] As illustrated in FIG. 1, vias 116 selectively couple the interconnect metal layers 110 and 108 to form electrical connections between devices 102, 104 and 106 of the integrated circuit 100. Further shown are vias 118 that provide electrical connections to elements of the devices 102, 104 and 106 and the first metal layer 108. [0018] In one embodiment, the sub-micron process is used to form metal layer M2 110 and metal layer M3 112. The sub-micron process uses many sub-layers to form a metal layer. In one embodiment, the sub-layers are alternating layers of Ti, TiN and Al alloys. Further in one embodiment, the top layer of the sub-layers of metal layer 110 (i.e. the sub-layer facing metal 112) is a TiN layer 120. The TiN layer 120 is used in this location because of its low reflective properties that aid in the pattering of metal layer 110. However, the presence of sub-layer 120 tends to increase the probability that cracks will form in an oxide layer separating the metal layer 110 from metal layer 112. In particular, because the TiN layer tends to be hard it doesn't yield when stress is applied. As a result, lateral stresses on the separating oxide tend to form cracks in the separating oxide layer. Further in another embodiment, a layer of TiW forms sub-layer 120. [0019] Embodiments, of the present invention reduce the probability of the cracks forming in the separating oxide layer 122. In one embodiment, the separating oxide layer 122 (i.e. the oxide layer that separates metal layer 110 from metal layer 112) is formed to be relatively thick. In one embodiment, the separating oxide layer 122 is formed to be at least 1.5 um thick. The use of a separating oxide layer 122 that is relatively thick reduces the probabilities of crack forming in the oxide layer 122. In further another embodiment, the separating oxide layer is generally a dielectric or insulating layer. Continue reading about Active area bonding compatible high current structures... Full patent description for Active area bonding compatible high current structures Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Active area bonding compatible high current structures patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. 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