Abstract:
The semiconductor device having electrostatic discharge protector includes a gate electrode on a first conductive type semiconductor substrate, a second conductive type source area in the semiconductor substrate at one lateral side of the gate electrode, and a second conductive type lightly doped drain area in the semiconductor substrate at the other lateral side of the gate electrode. A second conductive type heavily doped drain area is formed in a portion of the second conductive type lightly doped drain. The second conductive type heavily doped drain area is spaced from the gate electrode, to reduce/eliminate input capacitance of a high speed semiconductor device as well as improve an electrostatic discharge characteristic. A contact of conductive material forms an interface with the second conductive type heavily doped drain area that is recessed into the second conductive type heavily doped drain area.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a semiconductor device having an electrostatic discharge protector and fabricating method thereof.  
           [0003]    2. Description of Related Art  
           [0004]    Generally, a plurality of semiconductor devices manufactured on a wafer are cut by sawing so as to be packaged. When electrostatic discharge(hereinafter abbreviated ESD), which is high voltage amounting over 4000V instantly, generated from a human body is applied to the wafer or package during transportation or fabrication, the semiconductor device is destroyed.  
           [0005]    Such an inner circuit damage is caused by Joule&#39;s heat generated from electric charges which are inputted to an input pad and outputted to another terminal through an inner circuit. Namely, Joule&#39;s heat causes junction spiking and oxide breakage(rupture) and the like, thereby bringing about a damage on the inner circuit.  
           [0006]    In order to overcome such a damage, an ESD protection circuit is inserted therein so as to discharge the electric charges injected into the input pad by ESD directly to a terminal of a power supply before the electric charges exit through the inner circuit. Thus, a damage caused on the semiconductor device by ESD is prevented.  
           [0007]    An ESD protector is constructed with a field transistor consuming most of the current when ESD is applied between an input pad and an inner circuit, a gate ground NMOS transistor protecting a gate insulating layer of the inner circuit, and a resistor preventing excessive current from flowing into the NMOS transistor.  
           [0008]    In the ESD protection field transistor, n+ impurity diffusion areas, which become source and drain areas of the field transistor, are formed at both sides of a device isolating layer on a semiconductor substrate having a p-type well. The n+ impurity diffusion area at the one side is connected to an input pin, and the other n+ impurity diffusion area is connected to VSS.  
           [0009]    Such an ESD protector itself is destroyed when ESD is applied thereto, in which the drain area of the field transistor is mainly destroyed. This is because the drain area is directly connected to the input pin.  
           [0010]    A semiconductor device having an ESD protector and a fabricating method thereof are explained by referring to the attached drawings as follows.  
           [0011]    [0011]FIG. 1A illustrates a layout of an ESD transistor of an ESD protector according to the prior art, and FIG. 1B illustrates a cross-sectional view of the ESD transistor bisected along line I-I′.  
           [0012]    Referring to FIG. 1A and FIG. 1B, after defining an active area and a field area on a semiconductor substrate  10  having a p-type well, a device isolating layer  11  is formed in the field area of the semiconductor substrate  10 .  
           [0013]    Then, a gate electrode  13   a  having a gate insulating layer  12  there under is formed in one direction on the active area of the semiconductor substrate  10  isolated by the device isolation layer  11 . And, source and drain areas  15  and  16  are formed on the semiconductor substrate  10  at both lateral sides of the gate electrode  13   a , respectively.  
           [0014]    Successively, a first insulating interlayer  17 , having a plurality of first contact holes  18   a  and  18   b  exposing predetermined surface portions of the source and drain areas  15  and  16 , is formed on the substrate  10 . In this case, the first contact hole  18   b  on the drain area  16  is formed to leave at least a 2 interval from the gate electrode  13   a.    
           [0015]    If the interval between the gate electrode  13   a  and the first contact hole  18   b  is short enough to have a small resistance, the gate insulating layer  12  on a transistor channel part is broken by ESD from the gate electrode  13   a.    
           [0016]    And, the interval between the gate electrode  13   a  and first contact hole  18   b  is a major parameter of an input capacitance.  
           [0017]    A first conductive layer  19  is formed in the first contact holes  18   a  and  18   b,  and a first metal layer pattern  20  is formed not to be overlapped with the gate electrode  13   a  but to be connected with the first conductive layer  19  on the source and drain areas  15  and  16 . In this case, the first conductive layer  19  is formed of tungsten.  
           [0018]    A second insulating layer  21  having second contact holes  22   a  and  22   b  exposing predetermined portions of the first metal layer pattern  20 . A second conductive layer  23  is then formed in the second contact holes  22   a  and  22   b.  In this case, the second contact hole  22   b  in the drain area  16  is formed not to be overlapped with the first contact hole  18   b . And, the second conductive layer  23  is formed of tungsten.  
           [0019]    Subsequently, a second metal layer pattern  24  is formed over the source and drain areas  15  and  16  so as not to be overlapped with the gate electrode  13   a  but to be connected to the second conductive layer  23 .  
           [0020]    In this case, an input capacitance occupies 80 to 90% of an area size C×D of the drain area in FIG. 1A.  
           [0021]    Operation of the above-constructed ESD device is explained by the bipolar operation of a field transistor.  
           [0022]    When a high voltage is applied to the second metal layer pattern  24  formed over the drain area  16 , avalanche breakdown occurs in a drain area of a gate ground transistor(not shown in the drawing) connected to a resistor.  
           [0023]    A current flows through a junction of the field transistor after the junction breakdown. The current flow into the substrate  10  due to the junction breakdown is drained to a ground terminal(source area  15 ). In this case, when the current flow into the substrate  10  becomes large, a voltage difference is produced by a resistance of the substrate  10 , which is an intrinsic resistor having a large resistance. Thus, the source area  15  of the field transistor makes a substrate voltage increase.  
           [0024]    In this case, the source area  15  of the field transistor is an emitter of a bipolar transistor, the substrate  10  is a base, and the drain area  16  is a collector so as to carry out the bipolar operation. This is because an emitter-base junction becomes forward biased owing to the increasing base voltage of the bipolar transistor.  
           [0025]    [0025]FIGS. 2A to FIGS. 2F illustrate cross-sectional views of fabricating an ESD transistor according to the prior art.  
           [0026]    Referring to FIG. 2A, after an active area and a field area have been defined on a semiconductor substrate  10  having a p-type well, a trench is formed to have a predetermined depth in the substrate  10  by removing selectively the field area. An insulating layer is formed on the semiconductor substrate  10  including the trench.  
           [0027]    Subsequently, etch-back or CMP is carried out on an entire surface of the semiconductor substrate  10  so that the insulating layer remains only in the trench. Thus, a device insulating layer  11  having an STI(shallow trench isolation) structure is formed. A gate insulating layer  12  and a polysilicon layer  13  for forming a gate electrode are then formed on the semiconductor substrate  10 .  
           [0028]    After a photoresist has been formed on the polysilicon layer  13 , exposure and development are carried out on the photoresist so as to form a patterned photoresist  14  defining a gate area.  
           [0029]    Referring to FIG. 2B, a gate electrode  13   a  is formed by removing the polysilicon layer  13  and gate insulating layer  12  selectively using the patterned photoresist  14  as a mask.  
           [0030]    Referring to FIG. 2C, after the patterned photoresist  14  has been removed, source and drain areas  15  and  16  are formed on the semiconductor substrate  10  at both lateral sides of the gate electrode  13   a  respectively by carrying out impurity ion implantation on an entire surface of the semiconductor substrate  10  using the gate electrode  13   a  as a mask.  
           [0031]    In order to secure a sufficient drain resistance, a salicide layer is formed using a salicide protection mask (not shown in the drawing). And, the salicide layer (not shown in the drawing) is formed on a surface of the substrate, where gate electrodes and source/drain areas of other transistors are formed, by forming a Ti or Co layer on an entire surface of the semiconductor substrate  10  except the area where an ESD transistor is formed. Namely, the salicide layer is formed not to cover an area where the ESD transistor is to be formed.  
           [0032]    Referring to FIG. 2D, a first insulating interlayer  17  is formed on an entire surface of the semiconductor substrate including the gate electrode  13   a.  A plurality of first contact holes  18   a  and  18   b  are then formed by removing the first insulating interlayer  17  selectively so as to expose predetermined portions of the source and drain areas  15  and  16 . In this case, the first contact hole  18   b  formed in the drain area  16  is formed to leave an interval at least 2 from the gate electrode  13   a.    
           [0033]    Referring to FIG. 2E, a first conductive layer  19  is formed on the first insulating layer  17  including the first contact holes  18   a  and  18   b . Then, etch-back or CMP is carried out on the first conductive layer  19  so as to leave the first conductive layer  19  inside the first contact holes  18   a  and  18   b  only. In this case, the first conductive layer  19  is formed of tungsten.  
           [0034]    A first metal layer is deposited on the first insulating interlayer  17  including the first conductive layer  19 . A first metal layer pattern  20  is then formed on the source and drain areas  15  and  16  by removing portions of the first metal layer.  
           [0035]    Still referring to FIG. 2E, a second insulating interlayer  21  is formed on the first metal layer pattern  20 . A plurality of second contact holes  22   a  and  22   b  are formed by removing the second insulating interlayer  21  selectively so as to expose predetermined portions of the first metal layer pattern  20 . In this case, the second contact holes  22   a  and  22   b  are formed not to overlap with the first contact hole  18   b .  
           [0036]    Subsequently, as shown in FIG. 2F, a second conductive layer  23  is formed inside the second contact holes  22 . A second metal layer pattern  24  is formed selectively on the second insulating interlayer  21  including the second conductive layer  23 . In this case, the second conductive layer  23  is formed of tungsten.  
           [0037]    Then, a third metal layer pattern is formed after a contact hole is formed to expose the gate electrode for forming a wire, which is not shown in the drawing.  
           [0038]    Unfortunately, the semiconductor device having the ESD protector and fabricating method thereof according to the prior art has the problems as follows.  
           [0039]    An interval between a contact and a gate electrode for securing a resistance of a drain area is a major parameter for the ESD protector according to the prior art. Yet, the resistance is too small to prevent a gate insulating layer on a channel area of a transistor from being destroyed when ESD is applied to the gate electrode.  
           [0040]    Therefore, the interval between the contact and gate electrode is designed long enough to secure the resistance of the drain area.  
           [0041]    Thus, an area size of the drain area is so wide that an input capacitance increases when the interval between the contact and gate electrode is designed long enough to secure the resistance of the drain area.  
           [0042]    As a result, the increase of the input capacitance delays data input/output so as to interrupt the high speed of device operation.  
           [0043]    Moreover, a CSP(chip scale package) type high-speed-operating device is vulnerable to CDM(charged device mode).  
         SUMMARY OF THE INVENTION  
         [0044]    Accordingly, the present invention is directed to a semiconductor device having an electrostatic discharge protector and fabricating method thereof that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.  
           [0045]    The object of the present invention is to provide a semiconductor device having an electrostatic discharge protector and fabricating method thereof enabling to reduce/eliminate input capacitance of a high speed semiconductor device as well as improve an electrostatic discharge characteristic by reducing an interval between a contact and a gate electrode when the contact is formed to secure a resistance of a drain area of an ESD transistor.  
           [0046]    Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.  
           [0047]    To achieve these and other advantages, and in accordance with the purpose of the present invention as embodied and broadly described, a semiconductor device having an electrostatic discharge protector according to the present invention includes a gate electrode on a first conductive type semiconductor substrate, a second conductive type source area in the semiconductor substrate at a first lateral side of the gate electrode, a second conductive type lightly doped drain area in the semiconductor substrate at a second lateral side of the gate electrode, and a second conductive type heavily doped drain area in the second conductive type lightly doped drain, the second conductivity type heavily doped drain area being spaced from the gate electrode.  
           [0048]    Preferably, the second conductive type heavily doped drain area is formed deeper into the substrate than the second conductive type lightly doped drain area.  
           [0049]    Preferably, the present invention further includes a contact for a wiring process for the second conductive type heavily doped drain area.  
           [0050]    Preferably, a contact interface of the contact for the second conductive type heavily doped drain area is recessed into a surface of the second conductive type heavily doped drain area.  
           [0051]    Preferably, the second conductive type heavily doped drain area is spaced from the gate electrode so as to secure a desired resistance.  
           [0052]    Preferably, the first conductive type semiconductor substrate forms a p-type well using boron of which concentration is 1E17 to 3E17 ions/cm 3 , the second conductive type lightly doped drain area is doped with phosphorus of which concentration is 1E18 ions/cm 3 , and the second conductive type source/drain areas are doped with arsenic at a concentration over 1E20 ions/cm 3 .  
           [0053]    Preferably, a device isolation layer is formed in a field area of the semiconductor substrate defined by the field area and an active area.  
           [0054]    More preferably, the device isolation layer has a shallow trench isolation(STI) structure.  
           [0055]    In another aspect according to the present invention, a method of fabricating a semiconductor device having electrostatic discharge protector includes the steps of forming a gate electrode on a first conductive type semiconductor substrate, forming a second conductive type lightly doped source area in the semiconductor substrate at a first lateral side of the gate electrode and a second conductive type lightly doped drain area in the semiconductor substrate at a second lateral side of the gate electrode, and forming a second conductive type heavily doped source area at the first lateral side of the gate electrode and a second conductive type heavily doped drain area in the second conductive type lightly doped drain, the second conductivity type heavily doped drain area being spaced from the gate electrode.  
           [0056]    Preferably, the step of forming the second conductive type lightly doped source and drain areas forms the second conductive type lightly doped source and drain areas using the gate electrode as a mask; and the step of forming the second heavily doped source and drain areas includes forming a photoresist pattern exposing the second conductive type lightly doped source area and a predetermined portion of the second conductive type lightly doped drain area, and simultaneously forming the second conductive type heavily doped source area and the second conductive type heavily doped drain area.  
           [0057]    Preferably, the second conductive type heavily doped drain area is formed deeper into the substrate than the second conductive type lightly doped drain area.  
           [0058]    Preferably, the method further includes the steps of forming an insulating interlayer over the substrate, and forming a contact hole exposing a portion of the second conductive type heavily doped drain area by selectively removing the insulating interlayer.  
           [0059]    More preferably, a contact interface of the contact hole formed in the second conductive type heavily doped drain area is recessed into a surface of the second conductive type heavily doped drain area.  
           [0060]    Preferably, the second conductive type heavily doped drain area is spaced from the gate electrode so as to secure a desired resistance.  
           [0061]    Preferably, the first conductive type semiconductor substrate forms a p-type well using boron of which concentration is 1E17 to 3E17 ions/cm 3 , the second conductive type lightly doped drain area is doped with phosphorus of which concentration is 1E18 ions/cm 3 , and the second conductive type source/drain areas are doped with arsenic at a concentration over 1E20 ions/cm 3 .  
           [0062]    Preferably, a device isolation layer, after field and active areas are defined on the substrate, is formed in the field area of the semiconductor substrate.  
           [0063]    More preferably, the device isolation layer has a shallow trench isolation(STI) structure.  
           [0064]    It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0065]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.  
         [0066]    In the drawings:  
         [0067]    [0067]FIG. 1A illustrates a layout of an ESD transistor of an ESD protector according to the prior art;  
         [0068]    [0068]FIG. 1B illustrates a cross-sectional view of the ESD transistor bisected along line I-I′;  
         [0069]    [0069]FIGS. 2A to FIGS. 2F illustrate cross-sectional views of fabricating an ESD transistor according to the prior art;  
         [0070]    [0070]FIG. 3A illustrates a layout of an ESD transistor of an ESD protector according to an embodiment of the present invention;  
         [0071]    [0071]FIG. 3B illustrates a cross-sectional view of the ESD transistor bisected along line III-III′; and  
         [0072]    [0072]FIGS. 4A to FIGS. 4F illustrate cross-sectional views of fabricating an ESD transistor according to an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0073]    Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Where possible, the same reference numerals will be used to illustrate like elements throughout the specification.  
         [0074]    [0074]FIG. 3A illustrates a layout of an ESD transistor of an ESD protector according to an embodiment of the present invention and FIG. 3B illustrates a cross-sectional view of the ESD transistor bisected along line III-III′.  
         [0075]    Referring to FIG. 3A and FIG. 3B, a device isolating layer  101  having an STI(shallow trench isolation) structure is formed in a field area of a semiconductor substrate  100  where an active area and the field area are defined.  
         [0076]    Then, a gate electrode  103   a  having a gate insulating layer  12  underneath is formed in one direction on the active area of the semiconductor substrate  100 . And, a heavily doped source area  105   a  is formed at one lateral side of the gate electrode  103   a  of the semiconductor substrate  100 .  
         [0077]    A lightly doped drain area  106  is formed at the other lateral side of the gate electrode  103 a of the semiconductor substrate  100 . Additionally, a heavily doped drain area  106   a  is formed in the lightly doped drain area  106  leaving a predetermined interval far from the gate electrode  103   a.  In this case, the heavily doped drain area  106   a  is formed to provide a sufficient interval to secure a necessary resistance from the gate electrode  103   a.  In addition, the heavily doped drain area  106   a  is formed deeper than the lightly doped drain area  106 .  
         [0078]    When the semiconductor substrate  100  is a p-type substrate, the heavily doped source area  105   a  and the lightly/heavily doped drain areas  106  and  106   a  are doped with n-type impurities. Otherwise, the heavily doped source area  105   a  and the lightly/heavily doped drain areas  106  and  106   a  are doped with p-type impurities.  
         [0079]    Successively, a first insulating interlayer  107  having a plurality of first contact holes  109   a  and  109   b  exposing predetermined surface portions of the heavily doped source and drain areas  105   a  and  106   a  is formed on an entire surface of the substrate  100 . In this case, a contact interface of the first contact hole  109   b  is formed deeper than a surface of the heavily doped drain area  106   a .  
         [0080]    A first conductive layer  110  is formed in the first contact holes  109   a  and  109   b . And, a first metal layer pattern  111  is formed on the first insulating interlayer  107  including the first conductive layer  110 , and over but not in contact with the gate electrode  103   a . In this case, the first conductive layer  103   a  is formed of tungsten.  
         [0081]    A second insulating layer  112  having second contact holes  113   a  and  113   b  exposing predetermined portions of the first metal layer pattern  111   a.  A second conductive layer  114  is then formed in the second contact holes  113   a  and  113   b  only. In this case, the second contact holes  113   a  and  113   b  are formed not to be overlapped with the first contact holes  109   a  and  109   b . And, the second conductive layer  114  is formed of tungsten.  
         [0082]    Subsequently, a second metal layer pattern  115  is formed selectively on the second insulating layer  112  including the second conductive layer  114 , and over but not in contact with the gate electrode  103   a .  
         [0083]    Then, a third metal layer pattern (not shown) is formed after a contact hole (not shown) is formed to expose the gate electrode  103   a  for forming a wire, which is not shown in the drawing.  
         [0084]    [0084]FIGS. 4A to FIGS. 4F illustrate cross-sectional views of fabricating an ESD transistor according to an embodiment of the present invention.  
         [0085]    Referring to FIG. 4A, after an active area and a field area have been defined on a semiconductor substrate  100  having a p-type well, a trench is formed to have a predetermined depth in the substrate  100  by removing selectively the field area. An insulating layer(not shown in the drawing) is formed on the semiconductor substrate  100  including the trench. In this case, the p-type well of the semiconductor substrate  100  is formed using boron and impurity density of the p-type well is 1E17 to 3E17 ions/cm 3 .  
         [0086]    Subsequently, etch-back or CMP is carried out on an entire surface of the semiconductor substrate  100  so that the insulating layer remains only inside the trench. Thus, a device insulating layer  101  having an STI(shallow trench isolation) structure is formed. A gate insulating layer  102  and a polysilicon layer  103  for forming a gate electrode are then formed on the semiconductor substrate  100 .  
         [0087]    After a first photoresist has been formed on the polysilicon layer  103 , exposure and development are carried out on the first photoresist so as to form a first patterned photoresist  104  defining a gate area.  
         [0088]    Referring to FIG. 4B, a gate electrode  103   a  is formed by removing the polysilicon layer  103  and gate insulating layer  102  selectively using the first patterned photoresist  104  as a mask.  
         [0089]    Referring to FIG. 4C, after the first patterned photoresist  104  has been removed, a lightly doped source area  105  and a lightly doped drain area  106  are formed in the semiconductor substrate  100  at both lateral sides of the gate electrode  103   a  respectively by lightly carrying out impurity ion implantation on an entire surface of the semiconductor substrate  100  using the gate electrode  103   a  as a mask. In this case, the impurity ions for the lightly doped source/drain are phosphorus ions and the impurity concentration is 1E18 ions/cm 3 .  
         [0090]    In order to secure a sufficient drain resistance, a salicide layer is formed using a salicide protection mask(not shown in the drawing). And, the salicide layer(not shown in the drawing) is formed on a surface of the substrate, where gate electrodes and source/drain areas of other transistors are formed, by forming a Ti or Co layer on an entire surface of the semiconductor substrate  100  except the area where an ESD transistor is formed. Namely, the salicide layer is formed not to cover an area where the ESD transistor is to be formed.  
         [0091]    Referring to FIG. 4D, after a second photoresist has been formed on an entire surface of the semiconductor substrate  100 , exposure and development are carried out on the second photoresist so as to form a second patterned photoresist  107  exposing portions of the lightly doped source and drain areas  105   a  and  106 .  
         [0092]    Subsequently, by implanting impurity ions for heavily doped source/drain using the second patterned photoresist  107  and gate electrode  103   a  as a mask, a heavily doped source area  105   a  is formed at one lateral side of the gate electrode  103   a  and a heavily doped drain area  106   a  is formed to be located a predetermined interval from the gate electrode  103   a .  
         [0093]    In this case, the heavily doped drain area  106   a  is formed at a sufficient interval from the gate electrode  103   a  to secure a necessary resistance from the gate electrode  103   a . In addition, the heavily doped drain area  106   a  is formed deeper than the lightly doped drain area  106 .  
         [0094]    The impurity for the heavily doped source/drain is arsenic, and the concentration is about 1E20 ions/cm 3 .  
         [0095]    When the semiconductor substrate  100  is a p-type substrate, the heavily doped source area  105   a  and the lightly/heavily doped drain areas  106  and  106   a  are doped with n-type impurities. Otherwise, the heavily doped source area  105   a  and the lightly/heavily doped drain areas  106  and  106   a  are doped with p-type impurities.  
         [0096]    Referring to FIG. 4E, after the second patterned photoresist  107  has been removed, a first insulating interlayer  108  is formed on an entire surface of the semiconductor substrate  100  including the gate electrode  103   a . A plurality of first contact holes  109   a  and  109   b  are then formed by removing the first insulating interlayer  108  selectively so as to expose predetermined portions of the heavily doped source and drain areas  105   a  and  106   a.    
         [0097]    In this case, the first contact hole  109   b  exposing the heavily doped drain area  106  has the interval, which is shorter than that of the prior art, from the gate electrode  103   a .  
         [0098]    In this case, a contact interface of the first contact hole  109   b  formed in the heavily doped drain area  106   a  is formed deeper than a surface of the heavily doped drain area  106   a.    
         [0099]    Therefore, a vertical resistance at the contact interface of the first contact hole  109   b  is reduced.  
         [0100]    Referring to FIG. 4F, a first conductive layer  110  is formed on the first insulating layer  108  including the first contact holes  109   a  and  109   b . Then, etch-back or CMP is carried out on the first conductive layer  110  so as to leave the first conductive layer  110  inside the first contact holes  109   a  and  109   b  only. In this case, the first conductive layer  110  is formed of tungsten.  
         [0101]    A first metal layer is deposited on the first insulating interlayer  108  including the first conductive layer  110 . A first metal layer pattern  111  is then formed by removing the first metal layer  111  selectively. The first metal layer  111  is over but not in contact with the gate electrode  103 a.  
         [0102]    A second insulating interlayer  112  is formed on the first metal layer pattern  111 . A plurality of second contact holes  113   a  and  113   b  are formed by removing the second insulating interlayer  112  selectively so as to expose predetermined portions of the first metal layer pattern  111 .  
         [0103]    Subsequently, as shown in FIG. 4G, a second conductive layer  114  is formed inside the second contact holes  113   a  and  113 b. A second metal layer pattern  115  is formed selectively on the second insulating interlayer  112  including the second conductive layer  114 . The second metal layer pattern  115  covers but does not contact the gate electrode  103 a.  
         [0104]    Then, a third metal layer pattern (not shown) is formed after a contact hole (not shown) is formed to expose the gate electrode  103 a for forming a wire, which is not shown in the drawing.  
         [0105]    Therefore, a semiconductor device having electrostatic discharge protector and fabricating method thereof enables to reduce or eliminate an input capacitance since the reduced size of the ESD protector is realized.  
         [0106]    Accordingly, the present invention enables to design a device having low input capacitance as well as excellent ESD characteristics by settling the reciprocality between the ESD characteristics and input capacitance.  
         [0107]    Moreover, when maintaining the same input capacitance of the related art, the present invention is available for high-sped-operation devices such as DDR, Rambers DRAM, SRAM and the like by increasing twice the size of the ESD protector.  
         [0108]    The foregoing embodiments are merely exemplary and are not to be construed as limiting the present invention. The present teachings can be readily applied to other types of apparatuses. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art.