Abstract:
An approach for providing cross-coupling-based designs using diffusion contact structures is disclosed. Embodiments include providing first and second gate structures over a substrate; providing a gate cut region across the first gate structure, the second gate structure, or a combination thereof; providing a first gate contact over the first gate structure; providing a second gate contact over the second gate structure; and providing a diffusion contact structure coupling the first gate contact to the second gate contact, the diffusion contact structure having vertices within the gate cut region.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates to cross-coupling-based designs. The present disclosure is particularly applicable to designs in 14 nanometer (nm) technology nodes and beyond. 
       BACKGROUND 
       [0002]    Cross-coupling gate contact structures are important for standard cell design to achieve product area scaling goals of advanced technology nodes. However, as technology advances (e.g., 14 nm technology nodes and beyond), it may be difficult to construct a cross-coupling gate structure within a two-gate pitch region using traditional methods. 
         [0003]      FIG. 1  schematically illustrates a typical cross-coupling-based design. As shown, the design in  FIG. 1  includes gate structures  101  over one or more diffusion regions  103  having one or more diffusion contact structures  105 , gate contact structures  107  (gate contact structures  107   a  through  107   c ) over gate structures  101 , and via structures  109  (e.g., via0) to couple some of the gate contact structures  107  to the metal routing layer (e.g., metal1 routing layer) (not shown for illustrative convenience). To separate gate contact structures  107 , portions of some of the gate structures  101  are cut by gate cut regions  111 . As illustrated, the design in  FIG. 1  utilizes two gate cut regions  111  and one straight gate contact structure  107  over two gate structures  101  to achieve the cross-coupling-based design. Based on this design, for instance, for 20 nm technology nodes, two-gate pitch region  113  (which encompasses the gate contact structures  107 ) may be 140 nm to 200 nm in width (e.g., indicator  115 ) and 200 nm to 230 nm in length (e.g., indicator  117 ). 
         [0004]      FIG. 2  schematically illustrates another cross-coupling-based design. As shown, the design in  FIG. 2  similarly includes gate structures  201  over one or more diffusion regions  203  having one or more diffusion contact structures  205 , gate contact structures  207  (e.g., gate contact structures  207   a  through  207   d ) over gate structures  201 , and via structures  209  to couple some of the gate contact structures  207  to the metal routing layer (not shown for illustrative convenience). As depicted, the design in  FIG. 2  utilizes one gate cut region  211  to separate the gate contact structures  207  (as opposed to using two gate cut regions  111  for the design in  FIG. 1 ), and diffusion contact structure  213  to couple gate contact structure  207   b  on one gate structure  201  on one side of the gate cut region  211  to gate contact structure  207   c  on another gate structure  201  on the opposite side of the gate cut region  211 . In this example, two-gate pitch region  215  may, for instance, be 140 nm to 200 nm in width (e.g., indicator  217 ) and 300 nm in length (e.g., indicator  219 ). 
         [0005]    As technology advances, the designs in  FIGS. 1 and 2  may result in low diffusion efficiency, for instance, due to the lengths of the two-gate pitch regions  113  and  215 . Consequently, this low diffusion efficiency reduces the drive strength of the standard cell, negatively impacting its performance. In addition, the complicated gate contact structures in  FIGS. 1 and 2  (e.g., complicated with respect to patterning) may impose yield or reliability concerns as technology advances as a result of shorter spacing between adjacent gate structures. 
         [0006]    A need therefore exists for more effective and efficient cross-coupling-based designs, such as designs utilizing diffusion contact structures for cross-coupling, and enabling methodology. 
       SUMMARY 
       [0007]    An aspect of the present disclosure is a method for implementing a cross-coupling-based design using diffusion contact structures. 
         [0008]    Another aspect of the present disclosure is a device implemented with a cross-coupling-based design using diffusion contact structures. 
         [0009]    Additional aspects and other features of the present disclosure will be set forth in the description which follows and in part will be apparent to those having ordinary skill in the art upon examination of the following or may be learned from the practice of the present disclosure. The advantages of the present disclosure may be realized and obtained as particularly pointed out in the appended claims. 
         [0010]    According to the present disclosure, some technical effects may be achieved in part by a method including: providing first and second gate structures over a substrate; providing a gate cut region across the first gate structure, the second gate structure, or a combination thereof; providing a first gate contact over the first gate structure; providing a second gate contact over the second gate structure; and providing a diffusion contact structure coupling the first gate contact to the second gate contact, the diffusion contact structure having vertices within the gate cut region. 
         [0011]    Aspects of the present disclosure include providing the diffusion contact structure by: providing a first diffusion contact portion over the first gate structure; providing a second diffusion contact portion within the gate cut region; and providing a third diffusion contact portion over the second gate structure. Additional aspects include: coupling the first diffusion contact portion to a first side of the second diffusion contact portion; and coupling the third diffusion contact portion to a second side of the second diffusion contact portion, wherein the second side is opposite the first side. Certain aspects include: coupling the first diffusion contact portion to the first gate contact; and coupling the third diffusion contact portion to the second gate contact. Some aspects include the second diffusion contact portion being perpendicular to the first diffusion contact portion, the third diffusion contact portion, or a combination thereof. In other aspects, the second diffusion contact portion may not be perpendicular to the first diffusion contact portion, the third diffusion contact portion, or a combination thereof. 
         [0012]    Further aspects of the present disclosure include the first gate contact, the second gate contact, or a combination thereof being outside the gate cut region. Various aspects include providing the diffusion contact structure within a two-gate pitch region. Some aspects include the two-gate pitch region being 100 nm to 200 nm in length. 
         [0013]    An additional aspect of the present disclosure is a device including: first and second gate structures over a substrate; a gate cut region across the first gate structure, the second gate structure, or a combination thereof; a first gate contact over the first gate structure; a second gate contact over the second gate structure; and a diffusion contact structure coupling the first gate contact to the second gate contact, the diffusion contact structure having vertices within the gate cut region. 
         [0014]    Aspects include a device having the diffusion contact structure include: a first diffusion contact portion over the first gate structure; a second diffusion contact portion within the gate cut region; and a third diffusion contact portion over the second gate structure. Additional aspects include a device having the first diffusion contact portion being coupled to a first side of the second diffusion contact portion, the third diffusion contact portion being coupled to a second side of the second diffusion contact portion, and the second side being opposite the first side. Certain aspects include a device having the first diffusion contact portion being coupled to the first gate contact, and the third diffusion contact portion being coupled to the second gate contact. Some aspects include a device having the second diffusion contact portion that is perpendicular to the first diffusion contact portion, the third diffusion contact portion, or a combination thereof. 
         [0015]    Further aspects include a device having the first gate contact, the second gate contact, or a combination thereof being outside the gate cut region. Various aspects include a device having the diffusion contact structure being within a two-gate pitch region. Some aspects include a device having the two-gate pitch region being 100 nm to 200 nm in length. 
         [0016]    Another aspect of the present disclosure includes: providing first and second gate structures over a substrate; providing a gate cut region across the first gate structure, the second gate structure, or a combination thereof; providing a first gate contact over the first gate structure; providing a second gate contact over the second gate structure; providing a diffusion contact structure having a first diffusion contact portion over the first gate structure, a second diffusion contact portion within the gate cut region, and a third diffusion contact portion over the second gate structure; and coupling the diffusion contact structure to the first and second gate contacts. 
         [0017]    Additional aspects include: coupling the first diffusion contact portion to a first side of the second diffusion contact portion; and coupling the third diffusion contact portion to a second side of the second diffusion contact portion, wherein the second side is opposite the first side. Some aspects include: coupling the first diffusion contact portion to the first gate contact; and coupling the third diffusion contact portion to the second gate contact, wherein the first gate contact, the second gate contact, or a combination thereof are outside the gate cut region. Further aspects include providing the diffusion contact structure within a two-gate pitch region that is 100 nm to 200 nm in length. 
         [0018]    Additional aspects and technical effects of the present disclosure will become readily apparent to those skilled in the art from the following detailed description wherein embodiments of the present disclosure are described simply by way of illustration of the best mode contemplated to carry out the present disclosure. As will be realized, the present disclosure is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the present disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The present disclosure is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawing and in which like reference numerals refer to similar elements and in which: 
           [0020]      FIG. 1  schematically illustrates a typical cross-coupling-based design; 
           [0021]      FIG. 2  schematically illustrates another cross-coupling-based design; and 
           [0022]      FIG. 3  schematically illustrates a cross-coupling-based design using diffusion contact structures, in accordance with an exemplary embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of exemplary embodiments. It should be apparent, however, that exemplary embodiments may be practiced without these specific details or with an equivalent arrangement. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring exemplary embodiments. In addition, unless otherwise indicated, all numbers expressing quantities, ratios, and numerical properties of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” 
         [0024]    The present disclosure addresses and solves problems of low diffusion efficiency, reduced drive strength, and decreased reliability attendant upon cross-coupling gate contact structures. The present disclosure addresses and solves such problems, for instance, by, inter alia, providing a diffusion contact structure coupling a first gate contact over a first gate structure to the second gate contact over a second gate structure, with the diffusion contact structure having vertices within a gate cut region across the first gate structure, the second gate structure, or a combination thereof. 
         [0025]      FIG. 3  schematically illustrates a cross-coupling-based design using diffusion contact structures, in accordance with an exemplary embodiment of the present disclosure. As shown, the design in  FIG. 3  includes gate structures  301  over one or more diffusion regions  303  having one or more diffusion contact structures  305 . In certain aspects, the gate structures  301  may initially be formed with protective gap caps (not shown for illustrative convenience) that allow diffusion contact structures (e.g., diffusion contact structures  305 ) to overlap the gate structures  301  without shorting to the gate structures  301 . During processing, a portion of the gate cap may be removed for a particular gate structure  301 , for instance, to enable coupling of a diffusion contact structure, a gate contact structure (e.g., gate contact structures  307 ), etc., to that gate structure  301 . 
         [0026]    In addition, the design in  FIG. 3  includes gate contact structures  307  (e.g., gate contact structures  307   a  through  307   d ) over gate structures  301 , and via structures  309  to couple some of the gate contact structures  307  to the metal routing layer (not shown for illustrative convenience). As an example, the design in  FIG. 3  utilizes gate cut region  311  across two of the gate structures  301  to separate the gate contact structures  307  of those gate structures  301 , and diffusion contact structure  313  to couple gate contact structure  307   a  to gate contact structure  307   d.  As depicted, diffusion contact structure  313  crosses over gate cut region  311  to couple gate structures  307  (e.g., gate contact structures  307   a  and  307   d ) that are on opposite sides of the gate cut region  311  and on two different gate structures  301 . In addition, diffusion contact structure  313  has vertices within gate cut region  311  and is made up of at least three diffusion contact portions (e.g., left portion, center portion, right portion, etc.). 
         [0027]    It is noted, however, that diffusion contact structure  313  may be any shape for connecting the various gate contact structures  307 . For example, as an alternative to the Z-shape structure in  FIG. 3 , the diffusion contact structure  313  may be a straight 45 degree structure (not shown for illustrative convenience) coupling gate contact structure  307   a  to gate contact structure  307   d  (e.g., where the structure begins over one gate structure  301 , crosses over gate cut region  311  such that a middle portion is within the gate cut region, and ends over another gate structure  301 ). Moreover, with respect to the design in  FIG. 3 , two-gate pitch region  315  may have any suitable width (e.g., indicator  317 ), and a length of 100 nm to 200 nm (e.g., indicator  319 ). However, the two-gate pitch region  315  may alternatively have a length less than 100 nm or greater than 200 nm. 
         [0028]    Nonetheless, embodiments of the present disclosure enable higher diffusion efficiency due to a shorter length (e.g., vertical dimension as shown by indicator  319 ) of the two-gate pitch region  315 , for instance, when double patterning techniques are utilized for providing gate contact structures  307  and diffusion contact structures  313 . Embodiments of the present disclosure also facilitate further scaling of standard cells without sacrificing device performance. Moreover, due to the simplicity of the gate contact structures  307 , embodiments of the present disclosure are not prone to less yield or reliability concerns as a result of shorter spacing between adjacent gate structures  301 , making such embodiments easier to manufacture. By way of example, the gate contact structures  307  may, for instance, be as small as 20 nm by 20 nm. In certain aspects, the size of the gate contact structure  307  in a layout design may be any suitable single gate contact size is for the technology generation on which the design is being implemented (e.g., since it is not necessary for the gate contact structures  307  to directly connect two gates, the gate contact structures  307  can have a traditional hole shape and be very small). 
         [0029]    The embodiments of the present disclosure can achieve several technical effects, including increased diffusion efficiency, higher drive strength, and improved reliability. Embodiments of the present disclosure enjoy utility in various industrial applications as, for example, microprocessors, smart phones, mobile phones, cellular handsets, set-top boxes, DVD recorders and players, automotive navigation, printers and peripherals, networking and telecom equipment, gaming systems, and digital cameras. The present disclosure therefore enjoys industrial applicability in any of various types of highly integrated semiconductor devices, particularly in 14 nm technology nodes and beyond. 
         [0030]    In the preceding description, the present disclosure is described with reference to specifically exemplary embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the present disclosure, as set forth in the claims. The specification and drawings are, accordingly, to be regarded as illustrative and not as restrictive. It is understood that the present disclosure is capable of using various other combinations and embodiments and is capable of any changes or modifications within the scope of the inventive concept as expressed herein.