Abstract:
A semiconductor structure including a body-contacted finFET device and methods form manufacturing the same. The method may include forming one or more semiconductor fins on a SOI substrate, forming a semiconductive body contact region connected to the bottom of the fin(s) in the buried insulator region, forming a sacrificial gate structure over the body region of the fin(s), forming a source region on one end of the fin(s), forming a drain region on the opposite end of the fin(s), replacing the sacrificial gate structure with a metal gate, and forming electrical contacts to the source, drain, metal gate, and body contact region. The method may further include forming a body contact fin contemporaneously with the finFET fins that is in contact with the body contact region, through which electrical contact to the body contact region is made.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to semiconductor devices, and particularly methods of manufacturing body-contacted finFET devices. 
     BACKGROUND 
     Fin metal-oxide-semiconductor field effect transistor (Fin-MOSFET) is an emerging technology which provides solutions to metal-oxide-semiconductor field effect transistor (MOSFET) scaling problems at, and below, the 22 nm node. FinMOSFET structures include fin field effect transistors (finFETs) which include at least one narrow semiconductor fin gated on at least two opposing sides of each of the at least one semiconductor fin. FinFET structures may be formed on a semiconductor-on-insulator (SOI) substrate, because of the low source/drain diffusion to substrate capacitance and ease of electrical isolation by shallow trench isolation structures. 
     However, finFETs fabricated on an SOI substrate suffer from floating body effects, depending on fin thickness, as is well-known for conventional planar MOSFETs. The body of a finFET on an SOI substrate stores charge which is a function of the history of the device, hence becoming a floating body. As such, floating body finFETs experience threshold voltages which are difficult to anticipate and control, and which vary in time. The body charge storage effects result in dynamic sub-threshold voltage (sub-Vt) leakage and threshold voltage (Vt) mismatch among geometrically identical adjacent devices. Floating body effects in finFETs are particularly a concern in static random access memory (sRAM) cells, where Vt matching is extremely important as operating voltages continue to be scaled down. The floating body effects also pose leakage problems for pass gate devices. Further, one of the key concerns of floating body devices is the output conductance instability, a very important factor for analog circuit applications. In view of the above stated problems with finFETs fabricated on SOI substrates, it is desirable to eliminate body effects by building finFETs incorporating body contacts. In addition to this, having a body contact enables devices with multiple threshold voltages by controlling the body voltage. 
     Methods exist in the prior art for fabricating body-contacted finFETs. However, the prior art designs feature limitations that limit their application to finFETs with only a single fin. For example, U.S. Patent Application Publication No. US 2009/001464 A1 provides for a single-fin finFET with a body contact on the top surface of the fin, formed through the gate. Adapting this method for a multi-fin finFET would at least require forming a separate individual contact to each fin, greatly increasing process complexity, and is potentially impossible due to insufficient space to form multiple body-contacts. U.S. Pat. No. 7,485,520 provides for a single-fin finFET design, where a body contact is formed by removing material from a lower portion of a fin which rests on an adjacent semiconductor substrate, replacing the removed material with an insulating material to isolate the fin, and then forming a contact to the adjacent semiconductor substrate. The complexity of this process would be further increased if adapted to multi-fin designs, where the proximity of adjacent fins would reduce the efficacy of processes to add or remove material from lower portions of the fins. Therefore, a new method of forming body contacts for multi-fin finFETs is desirable. 
     SUMMARY 
     According to one embodiment of the present disclosure, a semiconductor structure comprising a finFET device with a body contact is provided. The structure may include one or more semiconductor fins on an silicon-on-insulator (SOI) substrate, a gate on the body region of the fin(s), a source contacting one end of the fin(s), a region contacting the opposite end of the fin(s), a semiconductive body-contact region formed in the insulator layer of the SOI substrate, where the body-contact region contacts the bottom of the fin(s), and electrical contacts formed to the source, the drain, the gate, and the body-contact region. Another embodiment may further include an additional fin formed on the SOI substrate in contact with the body-contact region, with the electrical contact to the body-contact region being formed through the additional fin. 
     According to another embodiment of the present disclosure, a method of manufacturing a semiconductor structure including a body-contacted finFET is provided. The method may include etching the top semiconductive layer of a SOI substrate to form at least one fin on the buried insulator layer, etching partially into the buried insulator underneath the fin(s) to form a recess region, filling the recess region with a semiconductive material to from a body-contact region in contact with the bottom of the fin(s), forming an insulator layer on the exposed top surface of the body contact, forming a sacrificial gate structure contacting the body region of the fin(s) but not fully covering the body contact region, forming a source contacting one end of the fin(s), forming a drain contacting the opposite end of the fin(s), replacing the sacrificial gate structure with a metal gate, and forming electrical contacts to the metal gate, the source, the drain, and the body-contact region. 
     According to another embodiment of the present disclosure, another method of manufacturing a semiconductor structure including a body-contacted finFET is provided. The method may include etching the top semiconductive layer of a SOI substrate to form at least one finFET fin and a body-contact fin on the buried insulator layer, etching partially into the buried insulator underneath the fins to form a recess region, filling the recess region with a semiconductive material to form a body-contact region in contact with the bottom of the fins, forming an insulator layer on the exposed top surface of the body-contact region, forming a sacrificial gate structure contacting the body region of the finFET fin(s) but not covering the body-contact fin, forming a source contacting one end of the finFET fin(s), forming a drain contacting the opposite end of the finFET fin(s), replacing the sacrificial gate structure with a metal gate, and forming electrical contacts to the metal gate, the source, the drain, and the body-contact fin. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIGS. 1A-13E  show sequential steps of an exemplary finFET structure according to a first embodiment of the present invention. Figures with the suffix “A” are top-down views of the exemplary structure. Figures with the suffix “B”, “C”, “D”, or “E” are vertical cross-sectional views of the exemplary structure along the plane indicated by line B, C, D, or E of the corresponding figure with the same numeric label and the suffix “A.” 
         FIGS. 14A-26E  show sequential steps of an exemplary finFET structure according to another embodiment of the present invention. Figures with the suffix “A” are top-down views of the exemplary structure. Figures with the suffix “B”, “C”, “D”, or “E” are vertical cross-sectional views of the exemplary structure along the plane indicated by line B, C, D, or E of the corresponding figure with the same numeric label and the suffix “A.” 
     
    
    
     Elements of the figures are not necessarily to scale and are not intended to portray specific parameters of the invention. For clarity and ease of illustration, dimensions of elements may be exaggerated. The detailed description should be consulted for accurate dimensions. The drawings are intended to depict only typical embodiments of the invention, and therefore should not be considered as limiting the scope of the invention. In the drawings, like numbering represents like elements. 
     DETAILED DESCRIPTION 
     Exemplary embodiments now will be described more fully herein with reference to the accompanying drawings, in which exemplary embodiments are shown. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. Rather, these exemplary embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of this disclosure to those skilled in the art. In the description, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments. 
     First Exemplary Embodiment 
     Referring to  FIGS. 1A-1E  depict a stack of layers from which an exemplary embodiment may be constructed. As seen in the side-views depicted in  FIGS. 1B-1E , the stack of layers includes a base substrate  110 , a buried oxide (BOX) layer  120 , a semiconductor-on-insulator (SOI) layer  130 , a pad oxide layer  140 , and a pad nitride layer  150 . Base substrate  110  may be made of any semiconductor material including, but not limited to: silicon, germanium, silicon-germanium alloy, silicon carbide, silicon-germanium carbide alloy, and compound (e.g. III-V and II-VI) semiconductor materials. Non-limiting examples of compound semiconductor materials include gallium arsenide, indium arsenide, and indium phosphide. BOX layer  120  may be formed from any of several dielectric materials. Non-limiting examples include, for example, oxides, nitrides and oxynitrides of silicon. Oxides, nitrides and oxynitrides of other elements are also envisioned. In addition, BOX layer  120  may include crystalline or non-crystalline dielectric material. Box layer  120  may be about 100-500 nm thick, preferably about 200 nm. SOI layer  130  may be made of any of the several semiconductor materials possible for base substrate  110 . In general, base substrate  110  and SOI layer  130  may include either identical or different semiconducting materials with respect to chemical composition, dopant concentration and crystallographic orientation. SOI layer  130  may be p-doped or n-doped with a dopant concentration in the range of 1×10 15 -1×10 18 /cm 3 , preferably about 1×10 15 /cm 3 . SOI layer  130  may be about 50-300 nm thick, preferably about 100 nm. Pad oxide layer  140  may be made of an insulating material such as, for example silicon oxide and may be about 5-20 nm thick, preferably about 10 nm. Pad nitride layer  150  may include an insulating material such as, for example, silicon nitride and may have be about 50-150 nm thick, preferably about 100 nm. 
     Referring to  FIGS. 2A-2E , at least one semiconductor fin  210  is formed by any method known in the art including, for example, photolithography and etching. It should be noted that a single finFET device may have one or more fins. In the depicted embodiment, three fins  210   a - 210   c  are formed. Fins  210   a - 210   c  contain fin bodies  130   a - 130   c , oxide masks  140   a - 140   c , and nitride masks  150   a - 150   c , respectively. Other embodiments may include as few as one fin. Fins  210   a - 210   c  may have a width of 10-50 nm, preferably about 20 nm. 
     Referring to  FIGS. 3A-3E , spacers  310   a - 310   c  are deposited on the sides of each semiconductor fin  210   a - 210   c , respectively, by any known method. Spacers  310   a - 310   c  may be formed, for example, by depositing a nitride layer over the semiconductor fins  210   a - 210   c  and then removing excess material using an anisotropic reactive ion etching (RIE) process (not shown). 
     Referring to  FIGS. 4A-4E  and  FIGS. 5A-5E , a region  510  is formed in BOX layer  120  by removing material from BOX layer  120 . This may be accomplished first by depositing a photoresist layer  410  on the surface of the structure of  FIGS. 3A-3E , as depicted in  FIGS. 4A-4E , and transferring the pattern of photoresist layer  410  to the BOX layer  120  using a wet etch process, as depicted in  FIGS. 5A-5E . The etching process should be selective to remove the material of the BOX layer  120  while not substantially removing any material of the fins  210   a - 210   c . Region  510  should extend fully underneath each fin at depth of about 10-100 nm, preferably 50 nm, as depicted in  FIG. 5A . Region  510  should have a width, measured perpendicular to the fins, of about 50-100 nm greater than n*(fin pitch), where n is the number of fins, and a length, measured parallel to the fins, of about 50-100 nm greater than the length of the gate (formed in  FIGS. 8A-8E ), preferably about 50 nm, with about 25 nm past each side of the gate. The length of fins  210   a - 210   c  will be greater than the width of region  510  so that ends of each fins  210   a - 210   c  remain in contact with BOX layer  120 . After region  510  is etched, photoresist layer  410  is removed (not shown). 
     Referring to  FIGS. 6A-6E , the region  510  (as depicted in  FIGS. 5A-5B ) may then be filled with a semiconductor layer  610 , so that the semiconductor layer  610  contacts the bottom of each fin  210   a - 210   c . Semiconductor layer  610  may be made of any semiconductor material including, but not limited to: silicon, germanium, silicon-germanium alloy, silicon carbide, silicon-germanium carbide alloy, and compound (e.g. III-V and II-VI) semiconductor materials. Non-limiting examples of compound semiconductor materials include gallium arsenide, indium arsenide, and indium phosphide. Semiconductor layer  610  may formed by any known method including, for example, a silicon epitaxial growth process. 
     Referring to  FIGS. 7A-7E , an oxide layer  711  is formed on top of semiconductor layer  610 . In the depicted embodiment, oxide layer  711  is formed by thermal oxidation, with the unoxidized portion of semiconductor layer  610  forming unoxidized layer  712 . The thickness of layer  711  determines the threshold voltage of the parasitic transistor formed. Therefore, oxide layer  711  may be about 5-10 nm thick. 
     As depicted in  FIGS. 8A-8E , a gate  810 , consisting of a sacrificial gate  811  and a gate cap  812  are formed over a center portion of each fin  210   a - 210   c . Sacrificial gate  811  may be made of a polysilicon material and may be about 100-200 nm thick, preferably about 100 nm. Gate cap  812  may be made of a nitride material and may be about 20-50 nm thick, preferably about 25 nm. Sacrificial gate  811  and gate cap  812  may be formed through any known method including, for example, depositing sacrificial gate  811  over the surface of the device, planarizing sacrificial gate  811 , depositing gate cap  812  on top of sacrificial gate  811 , and then removing material from outside the desired area using a reactive ion etching process. Gate  810  may underlap oxide layer  711  and unoxidized layer  712  by a sufficient distance so that a contact may later be formed to the unoxidized layer  712  in the underlapped region, preferably about 100 nm from the last fin edge. 
     Referring to  FIGS. 9A-9E , a spacer  813  is deposited around gate  810 . Spacer  813  may be formed, for example, by depositing a nitride layer over gate  810  and then removing excess material using an anisotropic reactive ion etching process (not shown). Spacer  813  must be thick enough to fully cover the sides of oxide layer  711  perpendicular to gate  810 , preferably about 10 nm. 
     Referring to  FIGS. 10A-10E , source/drain regions  910   a  and  910   b  are formed over fins  210   a - 210   c , in the regions not covered by gate  810  or spacer  813 . Spacers  310   a - 310   c , nitride masks  150   a - 150   c , and oxide masks  140   a - 140   c  ( FIGS. 2A-2E ) are removed from the exposed portions of fins  210   a - 210   c  ( FIGS. 9A-9E ) using known etching processes. A silicon-containing semiconductor material is then grown using known epitaxial processes over the exposed portions of fins  210   a - 210   c  ( FIGS. 9A-9E ) to form source/drain regions  910   a  and  910   b . For NMOS finFETs, source/drain regions  910   a  and  910   b  may be made of, for example, silicon or silicon carbide with a doping concentration of 1×10 20 -8×10 20 /cm 3  of arsenic or phosphorus, preferably 5×10 20 /cm 3 . For PMOS finFETs, source/drain regions  910   a  and  910   b  may be made of, for example, silicon or silicon germanium with a doping concentration of 1×10 20 -8×10 20 /cm 3  of boron, preferably 5×10 20 /cm 3 . It should be noted that, while source/drain regions  910   a  and  910   b  are depicted as has having uniform geometries in the provided figures, some known epitaxial processes result in non-ideal geometries where faceting may be present. 
     Referring to  FIGS. 11A-11E , an interlevel dielectric (ILD) layer  1010  is deposited over the structure of  FIGS. 10A-10E  and then planarized, using, for example, chemical mechanical planarization (CMP) to expose the top surface of sacrificial gate  811 . ILD layer  1010  may be made of, for example, TEOS, CVD oxide, or a stack of two more insulators including nitrides and oxides. 
     Referring to  FIGS. 12A-12E , sacrificial gate  811  ( FIGS. 11A-11E ) is removed and replaced with a metal gate, which may include interfacial layers, gate dielectrics, work function metals, and metal fill. Sacrificial gate  811  may be removed by any known method, including for example RIE or a wet etch containing ammonium hydroxide and dilute hydrofluoric acid (not shown). Spacers  310   a - 310   c , oxide masks  140   a - 140   c , and nitrides masks  150   a - 150   c  ( FIGS. 2A-2E ) are then removed from fins  210   a - 210   c  in the region exposed by the removal of sacrificial gate  811  ( FIGS. 11A-11E ). Interfacial layers  1211   a - 1211   c  are then formed over fin bodies  130   a - 130   c , respectively. Interfacial layers  1211   a - 1211   c  may be formed by oxidizing the exposed surfaces of fins  210   a - 210   c  and unoxidized layer  712  using known oxidation methods to form an oxide layer up to 10 angstroms thick. Various layers are then deposited in the region vacated by sacrificial gate  811  ( FIGS. 11A-11E ). The depicted embodiment includes a gate dielectric layer  1212 , Work-function metal  1213 , and a metal fill  1214 . Gate dielectric layer  1212  may be made of a high-k material and may be approximately 2 nm thick. Work-function metal  1213  may comprise multiple metal-containing layers and may be made of titanium nitride, tantalum nitride, or titanium-aluminum and may be 20-70 angstroms thick. Metal fill  1214  may be made of, for example, aluminum Other embodiments may include more or less metal layers depending on the application and types of device being formed. The composition of each metal layer may also vary and the process of selecting the material for each metal layer is known in the art. The structure is then planarized using chemical-mechanical planarization or any other known method to remove any excess metal from the top surface of ILD layer  1010 . 
     Referring to  FIGS. 13A-13E , contacts  1310   a - 1310   d  are formed to metal fill  1214 , source/drain  910   a , source/drain  910   b , and unoxidized layer  712 . First, contact holes are formed in ILD layer  1010  (shown in  FIGS. 12A-12E ) using known etching processes to expose a top surface of source/drains  910   a  and  910   b  and unoxidized layer  712  outside of metal gate  1210  (not shown). Silicide layers (not shown) are then formed on a top surface of source/drains  910   a  and  910   b  and unoxidized layer  712  by depositing a silicide metal, annealing the structure, and then removing unreacted metal (not shown). Silicide metals may include, for example, nickel, platinum, titanium, cobalt or some combination thereof. The contact holes are then filled with a contact metal, for example, copper and the structure is planarized to expose the top surface of metal fill  1214 . A dielectric layer  1301  is the deposited on top of the structure and contact holes are formed in dielectric layer  1301  to expose a top surface of metal gate  1210  and a top surface of the earlier formed contacts to source/drains  910   a  and  910   b  and unoxidized layer  712 . These contact holes are then filled with a contact metal, for example tungsten or copper, to form gate contact  1310   a , source/drain contact  1310   b , source/drain contact  1310   c , and body contact  1310   d.    
     Second Exemplary Embodiment 
     A second exemplary embodiment of the present invention includes an additional fin in contact with the buried semiconductor layer to potentially simplify formation of the body contact. Structures of the second exemplary embodiment that substantially correspond to structures of the first exemplary embodiment are represented as the prime of the corresponding reference number. 
     Referring to  FIGS. 14A-14E  depict a stack of layers from which an exemplary embodiment may be constructed. As seen in the side-views depicted in  FIGS. 1B-1E , the stack of layers includes a base substrate  110 ′, a buried oxide (BOX) layer  120 ′, a semiconductor-on-insulator (SOI) layer  130 ′, a pad oxide layer  140 ′, and a pad nitride layer  150 ′. The thickness and material composition of base substrate  110 ′, buried oxide (BOX) layer  120 ′, semiconductor-on-insulator (SOI) layer  130 ′, pad oxide layer  140 ′ is the same as base substrate  110 , buried oxide (BOX) layer  120 , semiconductor-on-insulator (SOI) layer  130 , pad oxide layer  140 , and pad nitride layer  150 , respectively. 
     Referring to  FIGS. 15A-15E , at least two semiconductor fins are formed by any known method including, for example, photolithography and etching processes. It should be noted that a single finFET device may have one or more fins. In the depicted embodiment, three transistor fins  210   a ′- 210   c ′ and one body contact fin  210   d ′ are formed. Fins  210   a ′- 210   d ′ contain fin bodies  130   a ′- 130   d ′. oxide masks  140   a ′- 140   d ′, and nitride masks  150   a ′- 150   d ′, respectively. Other embodiments may include as few one transistor fin. Fins  210   a ′- 210   d ′ may have a width of about 10-50 nm, preferably about 20 nm. Fin  210   d ′ may be formed approximately 100 nm away from the outer edge of the outermost transistor fin, in the depicted embodiment, fin  210   c′.    
     Referring to  FIGS. 16A-16E , spacers  310   a ′- 310   d ′ are deposited on the sides of each fin  210   a ′- 210   d ′, respectively, by any known method. Spacers  310   a ′- 310   d ′ may be formed, for example, by depositing a nitride layer over the semiconductor fins  210   a ′- 210   d ′ and then removing excess material using an anisotropic reactive ion etching (RIE) process (not shown). 
     Referring to  FIGS. 17A-17E  and  FIGS. 18A-18E , a region  510 ′ is formed in BOX layer  120 ′ by removing material from BOX layer  120 ′. This may be accomplished first by depositing a photoresist layer  410 ′ on the surface of the structure of  FIGS. 16A-16E , as depicted in  FIGS. 17A-17E , and transferring the pattern of photoresist layer  410 ′ to the BOX layer  120 ′; using a wet etch process, as depicted in  FIGS. 18A-18E . The etching process should be selective to remove the material of the BOX layer  120 ′ while not substantially removing any material of the fins  210   a ′- 210   d ′. Region  510 ′ should extend fully underneath each fin at depth of 10-100 nm, preferably 50 nm, as depicted in  FIG. 18A . Region  510 ′ should have a length, measured parallel to the fins, of about 50-100 nm greater than the length of the gate (formed in  FIGS. 21A-21E ), preferably about 50 nm, with about 25 nm past each side of the gate. The length of fins  210   a ′- 210   d ′ will be greater than the width of region  510 ′ so that ends of each fins  210   a ′- 210   d ′ remain in contact with BOX layer  120 ′. After region  510 ′ is etched, photoresist layer  410 ′ is removed (not shown). 
     Referring to  FIGS. 19A-19E , the region  510 ′ (as depicted in  FIGS. 18A-18B ) may then be filled with a semiconductor layer  610 ′, so that the semiconductor layer  610 ′ contacts the bottom of each fin  210   a ′- 210   d ′. Semiconductor layer  610 ′ may be made of any semiconductor material including, but not limited to: silicon, germanium, silicon-germanium alloy, silicon carbide, silicon-germanium carbide alloy, and compound (e.g. III-V and II-VI) semiconductor materials. Non-limiting examples of compound semiconductor materials include gallium arsenide, indium arsenide, and indium phosphide. Semiconductor layer  610 ′ may be formed by any known method including, for example, a silicon epitaxial growth process. 
     Referring to  FIGS. 20A-20E , an oxide layer  711 ′ is formed on top of semiconductor layer  610 ′. In the depicted embodiment, oxide layer  711 ′ is formed by thermal oxidation, with the unoxidized portion of semiconductor layer  610 ′ forming unoxidized layer  712 ′. The thickness of layer  711 ′ determines the threshold voltage of the parasitic transistor formed. Therefore, oxide layer  711 ′ may be about 5-10 nm thick. 
     As depicted in  FIGS. 21A-21E , a gate  810 ′, consisting of a sacrificial gate  811 ′ and a gate cap  812 ′ are formed over a center portion of each fin  210   a ′- 210   c ′. Fin  210   d ′ is not covered by gate  810 ′, so that a body-contact may be later formed to fin  210   d ′. The thickness and material composition of sacrificial gate  811 ′ and gate cap  812 ′ may be the same as sacrificial gate  811  and Gate cap  812 , respectively. Sacrificial gate  811 ′ and gate cap  812 ′ may be formed through an known method including, for example, depositing sacrificial gate  811 ′ over the surface of the device, planarizing sacrificial gate  811 ′, depositing gate cap  812 ′ on top of sacrificial gate  811 ′, and then removing material from outside the desired area using a reactive ion etching process. 
     Referring to  FIGS. 22A-22E , a spacer  813 ′ is deposited around gate  810 ′. Spacer  813 ′ may be formed, for example, by depositing a nitride layer over gate  810 ′ and then removing excess material using an anisotropic reactive ion etching process (not shown). Spacer  813 ′ may be thick enough to full cover the sides of oxide layer  711 ′ perpendicular to gate  810 ′, preferably about 10 nm. 
     Referring to  FIGS. 23A-23E , source/drain regions  910   a ′ and  910   b ′ are formed over fins  210   a ′- 210   c ′, in the regions not covered by gate  810 ′ or spacer  813 ′. Spacers  310   a ′- 310   c ′, nitride masks  150   a ′- 150   c ′, and oxide masks  140   a ′- 140   c ′ ( FIGS. 15A-15E ) are removed from the exposed portions of fins  210   a ′- 210   c ′ ( FIGS. 22A-22E ) using known etching processes. A silicon-containing semiconductor material is then grown using known epitaxial processes over the exposed portions of fins  210 ′ a - 210   c ′ ( FIGS. 22A-22E ) to form source/drain regions  910   a ′ and  910   b ′. The thickness and material composition of source/drain regions  910   a ′ and  910   b ′ may the same as source/drain regions  910   a  and  910   b . It should be noted that, while source/drain regions  910   a ′ and  910   b ′ are depicted as has having uniform geometries in the provided figures, some known epitaxial processes result in non-ideal geometries where faceting may be present. 
     Referring to  FIGS. 24A-24E , an interlevel dielectric (ILD) layer  1010 ′ is deposited over the structure of  FIGS. 10A-10E  (not shown) and then planarized, using, for example, chemical mechanical planarization (CMP) to expose the top surface of sacrificial gate  811 ′. ILD layer  1010 ′ may be made of, for example, TEOS, CVD oxide, or a stack of two more insulators including nitrides and oxides. 
     Referring to  FIGS. 25A-25E , sacrificial gate  811 ′ ( FIGS. 11A-11E ) is removed and replaced with a metal gate, which may include interfacial layers, gate dielectrics, work function metals, and metal fill. Sacrificial gate  811 ′ may be removed by any known method, including for example RIE or a wet etch containing ammonium hydroxide and dilute hydrofluoric acid (not shown). Spacers  310   a ′- 310   c ′, oxide masks  140   a ′- 140   c ′, and nitrides masks  150   a ′- 150   c ′ ( FIGS. 15A-15E ) are then removed from fins  210   a ′- 210   c ′ in the region exposed by the removal of sacrificial gate  811 ′ ( FIGS. 24A-24E ). Interfacial layers  1211   a ′- 1211   c ′, gate dielectric layer  1212 ′, work-function metal  1213 ′, and metal fill  1214 ′ are then formed in the same manner as interfacial layers  1211   a - 1211   c , gate dielectric layer  1212 , Work-function metal  1213 , and metal fill  1214  of the first exemplary embodiment. Other embodiments may include more or less metal layers depending on the application and types of device or devices being formed. The composition of each metal layer may also vary and the process of selecting the material for each metal layer is known in the art. The structure is then planarized using chemical-mechanical planarization or any other known method to remove any excess metal from the top surface of ILD layer  1010 ′. 
     Referring to  FIGS. 26A-26E , contacts  1310   a ′- 1310   d ′ are formed to metal gate  1210 ′, source/drain  910   a ′, source/drain  910   b ′, and fin body  130   d ′ of fin  210   d ′. First, contact holes are formed in ILD layer  1010 ′ using known etching processes to expose a top surface of source/drains  910   a ′ and  910   b ′ and fin body  130   d ′ (not shown). Silicide layers (not shown) are then formed on a top surface of source/drains  910   a ′ and  910   b ′ and fin body  130   d ′ by depositing a silicide metal, annealing the structure, and then removing unreacted metal (not shown). Silicide metals may include, for example, nickel, platinum, titanium, cobalt or some combination thereof. The contact holes are then filled with a contact metal, for example, copper and the structure is planarized to expose the top surface of metal fill  1214 ′. A second dielectric layer  1301 ′ is then deposited on top of the structure and contact holes are formed in dielectric layer  1301 ′ to expose a top surface of metal gate  1210 ′ and a top surface of the earlier formed contacts to source/drains  910   a ′ and  910   b ′ and fin body  130   d ′. These contact holes are then filled with a contact metal, for example tungsten or copper, to form gate contact  1310   a ′, source/drain contact  1310   b ′, source/drain contact  1310   c ′, and body contact  1310   d′.    
     The descriptions of the various embodiments of the present invention have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiment, the practical application or technical improvement over technologies found in the marketplace, or to enable other of ordinary skill in the art to understand the embodiments disclosed herein. It is therefore intended that the present invention not be limited to the exact forms and details described and illustrated but fall within the scope of the appended claims.