JP6033938B2 - Semiconductor device manufacturing method and semiconductor device - Google Patents

Description

  The present invention relates to a method for manufacturing a semiconductor device and a semiconductor device.

  Semiconductor integrated circuits, in particular integrated circuits using MOS transistors, are becoming increasingly highly integrated. Along with this high integration, the MOS transistors used therein have been miniaturized to the nano region. When the miniaturization of such a MOS transistor progresses, it is difficult to suppress the leakage current, and there is a problem that the occupied area of the circuit cannot be easily reduced due to a request for securing a necessary amount of current. In order to solve such a problem, a Surrounding Gate Transistor (hereinafter referred to as “SGT”) having a structure in which a source, a gate, and a drain are arranged in a vertical direction with respect to a substrate and a gate electrode surrounds a columnar semiconductor layer is proposed. (For example, see Patent Document 1, Patent Document 2, and Patent Document 3).

In a conventional SGT manufacturing method, a silicon pillar in which a nitride film hard mask is formed in a columnar shape is formed using a mask for drawing a silicon pillar, and a silicon pillar is drawn using a mask for drawing a planar silicon layer. A planar silicon layer is formed at the bottom, and a gate wiring is formed using a mask for drawing the gate wiring (see, for example, Patent Document 4).
That is, a silicon pillar, a planar silicon layer, and a gate wiring are formed using three masks.

  Further, in a conventional MOS transistor, a metal gate last process in which a metal gate is formed after a high temperature process is used in order to achieve both a metal gate process and a high temperature process (Non-patent Document 1). After forming a gate with polysilicon, an interlayer insulating film is deposited, then the polysilicon gate is exposed by chemical mechanical polishing, and after etching the polysilicon gate, a metal is deposited. Therefore, also in SGT, in order to make a metal gate process and a high temperature process compatible, it is necessary to use the metal gate last process which produces a metal gate after a high temperature process.

  Further, when the metal is embedded, if the upper part of the hole is narrower than the lower part of the hole, the upper part of the hole is filled first, and a hole is generated.

  In order to reduce the parasitic capacitance between the gate wiring and the substrate, the conventional MOS transistor uses the first insulating film. For example, in FINFET (Non-patent Document 2), a first insulating film is formed around one fin-like semiconductor layer, the first insulating film is etched back, the fin-like semiconductor layer is exposed, and the gate wiring and the substrate The parasitic capacitance between them is reduced. Therefore, also in SGT, it is necessary to use the first insulating film in order to reduce the parasitic capacitance between the gate wiring and the substrate. In SGT, since there is a columnar semiconductor layer in addition to the fin-shaped semiconductor layer, a device for forming the columnar semiconductor layer is required.

When the silicon pillar is thinned, the density of silicon is 5 × 10 ²² pieces / cm ³ , so that it becomes difficult for impurities to exist in the silicon pillar.

In the conventional SGT, it has been proposed to determine the threshold voltage by changing the work function of the gate material by setting the channel concentration to a low impurity concentration of 10 ¹⁷ cm ⁻³ or less (see, for example, Patent Document 5). ).

  In the planar MOS transistor, the sidewall of the LDD region is formed of polycrystalline silicon having the same conductivity type as that of the low concentration layer, and the surface carrier of the LDD region is induced by the work function difference, so that the oxide film sidewall LDD type MOS It has been shown that the impedance of the LDD region can be reduced as compared with a transistor (see, for example, Patent Document 6). The polycrystalline silicon sidewall is shown to be electrically insulated from the gate electrode. In the figure, it is shown that the polysilicon side wall and the source / drain are insulated by an interlayer insulating film.

JP-A-2-71556 Japanese Patent Laid-Open No. 2-188966 Japanese Patent Laid-Open No. 3-145761 JP 2009-182317 A JP 2004-356314 A JP 11-297984 A

IEDM2007 K. Mistry et.al, pp 247-250 IEDM2010 CC.Wu, et.al, 27.1.1-27.1.4.

  In view of the above, the present invention provides a method of manufacturing SGT, which is a gate last process, and a structure of SGT obtained as a result of forming a fin-like semiconductor layer, a columnar semiconductor layer, a gate electrode, and a gate wiring with two masks. For the purpose.

  The method for manufacturing a semiconductor device of the present invention includes a first step of forming a fin-like semiconductor layer on a semiconductor substrate and forming a first insulating film around the fin-like semiconductor layer, and after the first step, A second insulating film is formed around the fin-like semiconductor layer, a first polysilicon is deposited and planarized on the second insulating film, and a third insulating film is formed on the first polysilicon. A second resist for forming a gate wiring and a columnar semiconductor layer is formed in a direction perpendicular to the direction of the fin-shaped semiconductor layer, and the third insulating film and the first poly Etching silicon, the second insulating film, and the fin-like semiconductor layer to form a columnar semiconductor layer, a first dummy gate made of the first polysilicon, and a first hard mask made of the third insulating film Forming a second step and the second step Thereafter, a fourth insulating film is formed around the columnar semiconductor layer and the first dummy gate, a second polysilicon is deposited around the fourth insulating film, planarized, etched back, and A first hard mask is exposed, a sixth insulating film is deposited and etched to form a second hard mask on the side wall of the first hard mask, and the second polysilicon is etched. By doing so, a third step of forming the second dummy gate by remaining on the side walls of the first dummy gate and the columnar semiconductor layer, and after the third step, around the second dummy gate A sidewall made of a fifth insulating film is formed, and a second diffusion layer is formed above the fin-like semiconductor layer and below the columnar semiconductor layer, and left on the second diffusion layer. Of metal and semiconductor After the fourth step of forming the compound, and after the fourth step, an interlayer insulating film is deposited to expose the second dummy gate and the upper portion of the first dummy gate, and the second dummy gate, The first dummy gate is removed, a first gate insulating film is formed around the columnar semiconductor layer and inside the fifth insulating film, a first metal is deposited, and a gate electrode and a gate wiring are formed. After the fifth step and the fifth step, a second gate insulating film is deposited around the columnar semiconductor layer, on the gate electrode, and on the gate wiring, and a part of the second on the gate wiring is formed. The gate insulating film is removed, a second metal is deposited, etch back is performed, the second gate insulating film on the columnar semiconductor layer is removed, a third metal is deposited, and the third metal is deposited. Etching a metal and a portion of the second metal allows the second metal to A first contact surrounding the upper side wall of the columnar semiconductor layer; an upper portion of the first contact; and an upper portion of the columnar semiconductor layer connected to each other, and a second contact made of the second metal formed on the gate wiring. And a sixth step of forming a contact.

  The area of the upper surface of the second dummy gate is larger than the area of the lower surface of the second dummy gate.

  In the second step, a second insulating film is formed around the fin-like semiconductor layer, and the first polysilicon is deposited and planarized on the second insulating film, and the gate wiring and A second resist for forming the columnar semiconductor layer is formed in a direction perpendicular to the direction of the fin-shaped semiconductor layer, and the first polysilicon, the second insulating film, and the fin-shaped semiconductor are formed. The columnar semiconductor layer and the first dummy gate made of the first polysilicon are formed by etching a layer.

  Further, in the fourth step, the fifth insulating film is formed around the second dummy gate, etched and left in a sidewall shape, and a sidewall made of the fifth insulating film is formed. And forming the second diffusion layer above the fin-like semiconductor layer and below the columnar semiconductor layer, and forming the compound of the metal and the semiconductor on the second diffusion layer.

  In the fifth step, an interlayer insulating film is deposited and chemically mechanically polished to expose the second dummy gate and the upper portion of the first dummy gate, and the second dummy gate and the first dummy are exposed. Removing the gate, removing the second insulating film and the fourth insulating film, forming a first gate insulating film around the columnar semiconductor layer and inside the fifth insulating film; The metal is deposited and etched back to form the gate electrode and the gate wiring.

  The method further includes depositing a contact stopper film after the fourth step.

  The method further includes a step of removing the first gate insulating film after the fifth step.

  The metal work function of the first contact is between 4.0 eV and 4.2 eV.

  The metal work function of the first contact is between 5.0 eV and 5.2 eV.

  The semiconductor device of the present invention is formed on the fin-like semiconductor layer, the fin-like semiconductor layer formed on the semiconductor substrate, the first insulating film formed around the fin-like semiconductor layer, and the fin-like semiconductor layer. A columnar semiconductor layer, a first gate insulating film formed around the columnar semiconductor layer, a gate electrode made of metal formed around the first gate insulating film, and connected to the gate electrode A gate wiring made of a metal extending in a direction orthogonal to the fin-shaped semiconductor layer, the gate electrode, the first gate insulating film formed on the periphery and bottom of the gate wiring, and the fin-shaped semiconductor layer. A second diffusion layer formed at an upper portion and a lower portion of the columnar semiconductor layer; a second gate insulating film formed around an upper sidewall of the columnar semiconductor layer; and around the second gate insulating film Second gold formed An upper surface area of the gate electrode and the gate wiring is larger than an area of a lower surface of the gate electrode and the gate wiring, and an upper portion of the first contact and the columnar semiconductor layer. The upper part is connected.

  In addition, a second contact made of the second metal is formed on the gate wiring.

  The work function of the second metal of the first contact is between 4.0 eV and 4.2 eV.

  The work function of the second metal of the first contact is between 5.0 eV and 5.2 eV.

  According to the present invention, a fin-like silicon layer, a columnar silicon layer, a gate electrode and a gate wiring are formed with two masks, and a method for producing SGT, which is a gate last process, and the resulting SGT structure are provided. be able to.

  A first step of forming a fin-like semiconductor layer on the semiconductor substrate and forming a first insulating film around the fin-like semiconductor layer; and a second step around the fin-like semiconductor layer after the first step. A first polysilicon is deposited and planarized on the second insulating film, a third insulating film is formed on the first polysilicon, and a gate wiring and a columnar semiconductor layer are formed. A second resist is formed in a direction perpendicular to the direction of the fin-like semiconductor layer, and the third insulating film, the first polysilicon, the second insulating film, and the Etching the fin-like semiconductor layer to form a columnar semiconductor layer, a first dummy gate made of the first polysilicon, and a first hard mask made of the third insulating film; After the two steps, the columnar semiconductor layer and the first A fourth insulating film is formed around the dummy gate, and second polysilicon is deposited and planarized around the fourth insulating film, etched back, and the first hard mask is exposed, A second hard mask is formed on the side wall of the first hard mask by depositing and etching the insulating film, and the second polysilicon is etched to form the first dummy gate and the first hard gate. And a third step of forming a second dummy gate, which is left on the side wall of the columnar semiconductor layer, thereby forming a fin-shaped semiconductor layer, a columnar semiconductor layer, and a gate electrode later with two masks. As a result, the first dummy gate and the second dummy gate to be the gate wiring can be formed, and the number of steps can be reduced.

  Further, the first and second hard masks prevent the metal and semiconductor compound from being formed on the first and second dummy gates, and the metal and semiconductor compound is formed only on the fin-like semiconductor layer. be able to.

  Further, when etching the second polysilicon, by using reverse taper etching, the area of the upper surface of the second dummy gate can be made larger than the area of the lower surface of the second dummy gate. When the metal for embedding is embedded, voids can be prevented from being formed.

  Misalignment between the columnar semiconductor layer and the gate wiring can be eliminated.

  In addition, the first dummy gate and the second dummy gate are made of polysilicon, and after that, an interlayer insulating film is deposited, and then the first dummy gate and the second dummy gate are exposed by chemical mechanical polishing. Since the conventional metal gate last manufacturing method of depositing metal after etching the gate can be used, the metal gate SGT can be easily formed.

  If the metal gate last process is applied to SGT, the upper part of the columnar semiconductor layer is covered with the polysilicon gate, so that it is difficult to form a diffusion layer on the upper part of the columnar semiconductor layer. Therefore, a diffusion layer is formed on the columnar semiconductor layer before forming the polysilicon gate. On the other hand, in the present invention, the diffusion layer is not formed on the upper part of the columnar semiconductor layer, and the upper part of the columnar semiconductor layer can function as an n-type semiconductor layer or a p-type semiconductor layer depending on a work function difference between the metal and the semiconductor. Therefore, it is possible to reduce the step of forming the diffusion layer on the columnar semiconductor layer.

  In addition, the gate electrode and the gate wiring can be insulated from the columnar semiconductor layer and the fin-shaped semiconductor layer by the first gate insulating film formed around and at the bottom of the gate electrode and the gate wiring.

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  Below, the manufacturing process for forming the structure of SGT which concerns on embodiment of this invention is demonstrated with reference to FIGS.

  First, a first step of forming a fin-like semiconductor layer on a semiconductor substrate and forming a first insulating film around the fin-like semiconductor layer is shown. In this embodiment, the semiconductor substrate is silicon, but other semiconductors may be used as long as they are semiconductors.

  As shown in FIG. 2, a first resist 102 for forming a fin-like silicon layer is formed on the silicon substrate 101.

  As shown in FIG. 3, the silicon substrate 101 is etched to form a fin-like silicon layer 103. Although the fin-like silicon layer is formed using a resist as a mask this time, a hard mask such as an oxide film or a nitride film may be used.

  As shown in FIG. 4, the first resist 102 is removed.

  As shown in FIG. 5, a first insulating film 104 is deposited around the fin-like silicon layer 103. An oxide film formed by high-density plasma or an oxide film formed by low-pressure CVD (Chemical Vapor Deposition) may be used as the first insulating film.

  As shown in FIG. 6, the 1st insulating film 104 is etched back and the upper part of the fin-like silicon layer 103 is exposed. The process up to here is the same as the manufacturing method of the fin-like silicon layer of Non-Patent Document 2.

  Thus, the first step of forming the fin-like semiconductor layer on the semiconductor substrate and forming the first insulating film around the fin-like semiconductor layer is shown.

  Next, a second insulating film is formed around the fin-like semiconductor layer, a first polysilicon is deposited and planarized on the second insulating film, and a third is formed on the first polysilicon. A second resist for forming a gate wiring and a columnar semiconductor layer is formed in a direction perpendicular to the direction of the fin-shaped semiconductor layer, and the third insulating film and the first insulating film are formed. 1 polysilicon, the second insulating film, and the fin-like semiconductor layer are etched, whereby a columnar semiconductor layer, a first dummy gate made of the first polysilicon, and a first insulating film made of the third insulating film. The 2nd process of forming a hard mask is shown.

  As shown in FIG. 7, a second insulating film 105 is formed around the fin-like silicon layer 103. The second insulating film 105 is preferably an oxide film.

  As shown in FIG. 8, a first polysilicon 106 is deposited on the second insulating film 105 and planarized.

  As shown in FIG. 9, a third insulating film 107 is formed on the first polysilicon 106. The third insulating film 107 is preferably a nitride film.

  As shown in FIG. 10, a second resist 108 for forming the gate wiring and the columnar silicon layer is formed in a direction perpendicular to the direction of the fin-shaped silicon layer 103.

  As shown in FIG. 11, by etching the third insulating film 107, the first polysilicon 106, the second insulating film 105, and the fin-like silicon layer 103, the columnar silicon layer 109 and the first silicon layer 109 are etched. A first dummy gate 106a made of one polysilicon and a first hard mask 107a made of a third insulating film are formed.

  As shown in FIG. 12, the second resist 108 is removed.

  As described above, the second insulating film is formed around the fin-like semiconductor layer, the first polysilicon is deposited and planarized on the second insulating film, and the third polysilicon is formed on the first polysilicon. A second resist for forming a gate wiring and a columnar semiconductor layer is formed in a direction perpendicular to the direction of the fin-shaped semiconductor layer, and the third insulating film and the first insulating film are formed. 1 polysilicon, the second insulating film, and the fin-like semiconductor layer are etched, whereby a columnar semiconductor layer, a first dummy gate made of the first polysilicon, and a first insulating film made of the third insulating film. A second step of forming a hard mask is shown.

  Next, after the second step, a fourth insulating film is formed around the columnar semiconductor layer and the first dummy gate, and second polysilicon is deposited around the fourth insulating film. Planarizing, etching back, exposing the first hard mask, depositing a sixth insulating film, and etching to form a second hard mask on a sidewall of the first hard mask; A third step of forming a second dummy gate by etching the second polysilicon to remain on the side walls of the first dummy gate and the columnar semiconductor layer is shown.

  As shown in FIG. 13, a fourth insulating film 110 is formed around the columnar silicon layer 109 and the first dummy gate 106a. The fourth insulating film 110 is preferably an oxide film.

  As shown in FIG. 14, the second polysilicon 113 is deposited around the fourth insulating film 110 and planarized.

  As shown in FIG. 15, the second polysilicon 113 is etched back to expose the first hard mask 107a.

  As shown in FIG. 16, the 6th insulating film 114 is deposited. The sixth insulating film 114 is preferably a nitride film.

  As shown in FIG. 17, the 6th insulating film 114 is etched, The 2nd hard mask 114a is formed in the side wall of the said 1st hard mask 107a.

  As shown in FIG. 18, the second polysilicon 113 is etched to remain on the side walls of the first dummy gate 106a and the columnar semiconductor layer 109, thereby forming a second dummy gate 113a. When etching the second polysilicon 113, the area of the upper surface of the second dummy gate 113a can be made larger than the area of the lower surface of the second dummy gate 113a by using reverse taper etching. When embedding the metal for the gate, it is possible to prevent voids from being formed.

  As described above, after the second step, the fourth insulating film is formed around the columnar semiconductor layer and the first dummy gate, and the second polysilicon is deposited around the fourth insulating film. Planarizing, etching back, exposing the first hard mask, depositing a sixth insulating film, and etching to form a second hard mask on a sidewall of the first hard mask; A third step is shown in which the second dummy gate is formed by etching the second polysilicon so as to remain on the side walls of the first dummy gate and the columnar semiconductor layer.

  Next, after the third step, a sidewall made of a fifth insulating film is formed around the second dummy gate to form a sidewall made of a fifth insulating film, and the upper part of the fin-like semiconductor layer and the columnar semiconductor are formed. A fourth step is shown in which a second diffusion layer is formed under the layer, and a metal and semiconductor compound is formed on the second diffusion layer.

  As shown in FIG. 19, a fifth insulating film 115 is formed around the second dummy gate 113a. The fifth insulating film 115 is preferably a nitride film.

  As shown in FIG. 20, the fifth insulating film 115 is etched and left in the shape of a sidewall to form a sidewall 115a made of the fifth insulating film.

  As shown in FIG. 21, impurities are introduced to form a second diffusion layer 116 above the fin-like silicon layer 103 and below the columnar silicon layer 109. In the case of an n-type diffusion layer, it is preferable to introduce arsenic or phosphorus. In the case of a p-type diffusion layer, it is preferable to introduce boron. Impurity introduction may be performed before the fifth insulating film is formed.

  As shown in FIG. 22, a metal-semiconductor compound 117 is formed on the second diffusion layer 116. At this time, the first and second hard masks 107 a and 114 a prevent the formation of a compound of a metal and a semiconductor on the first and second dummy gates 106 a and 113 a, and the fin-like semiconductor layer 103 is formed. Only a compound of a metal and a semiconductor can be formed.

  As described above, after the third step, a sidewall made of a fifth insulating film is formed around the second dummy gate to form a sidewall made of the fifth insulating film, and the upper part of the fin-like semiconductor layer and the columnar semiconductor are formed. A fourth step is shown in which a second diffusion layer is formed below the layer, and a metal and semiconductor compound is formed on the second diffusion layer.

  Next, after the fourth step, an interlayer insulating film is deposited, the second dummy gate and the upper portion of the first dummy gate are exposed, and the second dummy gate and the first dummy gate are formed. 5 shows a fifth step of removing, forming a first gate insulating film around the columnar semiconductor layer and inside the fifth insulating film, depositing a first metal, and forming a gate electrode and a gate wiring. .

  As shown in FIG. 23, a contact stopper film 118 is deposited, and an interlayer insulating film 119 is deposited. The contact stopper film 118 is preferably a nitride film.

  As shown in FIG. 24, chemical mechanical polishing is performed to expose the upper portions of the second dummy gate 113a and the first dummy gate 106a.

  As shown in FIG. 25, the second dummy gate 113a and the first dummy gate 106a are removed.

  As shown in FIG. 26, the second insulating film 105 and the fourth insulating film 110 are removed.

  As shown in FIG. 27, the first gate insulating film 120 is formed around the columnar silicon layer 109 and inside the fifth insulating film 115a.

  As shown in FIG. 28, the 1st metal 121 is deposited.

  As shown in FIG. 29, the first metal 121 is etched back to expose the upper portion of the columnar silicon layer 109. A gate electrode 121 a is formed around the columnar silicon layer 109. In addition, the gate wiring 121b is formed. The gate electrode 121a and the gate wiring 121b are insulated from the columnar silicon layer 109 and the fin-shaped silicon layer 103 by the first gate insulating film 120 formed around and at the bottom of the gate electrode 121a and the gate wiring 121b. be able to.

  As described above, after the fourth step, an interlayer insulating film is deposited, the second dummy gate and the upper portion of the first dummy gate are exposed, and the second dummy gate and the first dummy gate are formed. A fifth step is shown in which a first gate insulating film is formed around the columnar semiconductor layer and inside the fifth insulating film, a first metal is deposited, and a gate electrode and a gate wiring are formed. It was done.

  Next, after the fifth step, a second gate insulating film is deposited around the columnar semiconductor layer, on the gate electrode, and on the gate wiring, and a part of the second gate insulating film on the gate wiring is formed. , Depositing a second metal, performing etch back, removing the second gate insulating film on the columnar semiconductor layer, depositing a third metal, and depositing the third metal and the second metal By etching a part of the metal 2, the second metal connects the first contact that surrounds the upper sidewall of the columnar semiconductor layer, the upper portion of the first contact, and the upper portion of the columnar semiconductor layer. A sixth step of forming a second contact made of the second metal formed on the gate wiring is shown.

  As shown in FIG. 30, the exposed first gate insulating film 120 is removed. The first gate insulating film 120 becomes the first gate insulating film 120a.

  As shown in FIG. 31, a second gate insulating film 122 is deposited around the columnar silicon layer 109, the gate electrode 121a, and the gate wiring 121b.

  As shown in FIG. 32, a third resist 123 for removing a part of the second gate insulating film 122 on the gate wiring 121b is formed.

  As shown in FIG. 33, a part of the second gate insulating film 122 on the gate wiring 121b is removed.

  As shown in FIG. 34, the third resist 123 is removed.

  As shown in FIG. 35, a second metal 124 is deposited. The metal work function of the second metal 124 is preferably between 4.0 eV and 4.2 eV when the transistor is n-type. The work function of the second metal 124 is preferably between 5.0 eV and 5.2 eV when the transistor is p-type.

  As shown in FIG. 36, the second metal 124 is etched back to form contact lines 124a.

  As shown in FIG. 37, the second gate insulating film 122 on the columnar silicon layer 109 is removed. The second gate insulating film 122 becomes the second gate insulating film 122a.

  As shown in FIG. 38, the 4th resist 125 for forming a contact hole is formed.

  As shown in FIG. 39, the contact hole 126 is formed by etching the interlayer insulating film 119 and the contact stopper film 118.

  As shown in FIG. 40, the 4th resist 125 is removed.

  As shown in FIG. 41, the 3rd metal 127 is deposited. Thereby, the third contact 128 is formed.

  As shown in FIG. 42, fifth resists 129, 130, and 131 are formed.

  As shown in FIG. 43, the third metal 127 and the contact line 124a are etched to form the second metal on the first contact 124b surrounding the columnar silicon layer 109 and the gate wiring 121b. The second contact 124c made of the second metal and the metal wiring 127a, 128b, 128c are formed. The upper part of the first contact 124b and the upper part of the columnar silicon layer 109 are connected by a metal wiring 127b.

  As shown in FIG. 44, the fifth resists 129, 130, and 131 are removed.

  As described above, after the fifth step, a second gate insulating film is deposited around the columnar semiconductor layer, on the gate electrode, and on the gate wiring, and a part of the second gate insulating film on the gate wiring is formed. , Depositing a second metal, performing etch back, removing the second gate insulating film on the columnar semiconductor layer, depositing a third metal, and depositing the third metal and the second metal By etching a part of the metal 2, the second metal connects the first contact that surrounds the upper sidewall of the columnar semiconductor layer, the upper portion of the first contact, and the upper portion of the columnar semiconductor layer. Thus, the sixth step of forming the second contact made of the second metal formed on the gate wiring is shown.

  As described above, the fin-like semiconductor layer, the columnar semiconductor layer, the gate electrode, and the gate wiring are formed using two masks, and the method for manufacturing SGT, which is a gate last process, is shown.

  A structure of a semiconductor device obtained by the manufacturing method is shown in FIG.

  The semiconductor device of FIG. 1 is formed on the fin-like silicon layer 103, the first insulating film 104 formed around the fin-like silicon layer, and the fin-like silicon layer 103. Columnar silicon layer 109, first gate insulating film 120a formed around columnar silicon layer 109, gate electrode 121a made of metal formed around first gate insulating film 120a, Gate wiring 121b made of a metal extending in a direction orthogonal to the fin-like silicon layer 103 connected to the gate electrode 121a, and the first and second gate electrodes 121a and the gate wiring 121b are formed around and at the bottom. Gate insulating film 120 a, a second layer formed on the upper part of the fin-like silicon layer 103 and on the lower part of the columnar silicon layer 109. A diffusion layer 116, a second gate insulating film 122a formed around the upper sidewall of the columnar silicon layer 109, and a second metal made of a second metal formed around the second gate insulating film 122a. One contact 124b, the upper part of the first contact 124b and the upper part of the columnar silicon layer 109 are connected, and the area of the upper surface of the gate electrode 121a and the gate wiring 121b is the gate It is larger than the area of the lower surface of the electrode 121a and the gate wiring 121b. .

  In addition, a second contact 124c made of the second metal is formed on the gate wiring 121b.

  Since it is formed by self-alignment, misalignment between the columnar silicon layer 109 and the gate wiring 121b can be eliminated.

  In addition, the gate electrode 121a and the gate wiring 121b can be insulated from the columnar silicon layer 109 and the fin-shaped silicon layer 103 by the gate insulating film 120a formed around and at the bottom of the gate electrode 121a and the gate wiring 121b. it can.

  It should be noted that the present invention can be variously modified and modified without departing from the broad spirit and scope of the present invention. Further, the above-described embodiment is for explaining an example of the present invention, and does not limit the scope of the present invention.

For example, in the above embodiment, a method of manufacturing a semiconductor device in which p-type (including p ⁺ -type) and n-type (including n ⁺ -type) are opposite in conductivity type, and a semiconductor obtained thereby An apparatus is naturally included in the technical scope of the present invention.

101. Silicon substrate 102. First resist 103. Fin-like silicon layer 104. First insulating film 105. Second insulating film 106. First polysilicon 106a. First dummy gate 107. Third insulating film 107a. First hard mask 108. Second resist 109. Columnar silicon layer 110. Fourth insulating film 113. Second polysilicon 113a. Second dummy gate 114. Sixth insulating film 114a. Second hard mask 115. Fifth insulating film 115a. Sidewall 116. Second diffusion layer 117. Compound of metal and semiconductor 118. Contact stopper film 119. Interlayer insulating film 120. First gate insulating film 120a. First gate insulating film 121. First metal 121a. Gate electrode 121b. Gate wiring 122. Second gate insulating film 122a. Second gate insulating film 123. Third resist 124. Second metal 124a. Contact line 124b. First contact 124c. Second contact 125. Fourth resist 126. Contact hole 127. Third metal 127a. Metal wiring 127b. Metal wiring 127c. Metal wiring 128. Third contact 129. Fifth resist 130. Fifth resist 131. 5th resist

Claims (4)

A fin-like semiconductor layer formed on a semiconductor substrate;
A first insulating film formed around the fin-like semiconductor layer;
A columnar semiconductor layer formed on the fin-shaped semiconductor layer;
A first gate insulating film formed around the columnar semiconductor layer;
A gate electrode made of metal formed around the first gate insulating film;
A gate wiring made of a metal extending in a direction orthogonal to the fin-like semiconductor layer connected to the gate electrode;
The first gate insulating film formed on and around the gate electrode and the gate wiring;
A second gate insulating film formed around the upper sidewall of the columnar semiconductor layer;
A first contact made of a second metal formed around the second gate insulating film;
Have
The area of the upper surface of the gate electrode and the gate wiring is larger than the area of the lower surface of the gate electrode and the gate wiring, and the upper part of the first contact and the upper part of the columnar semiconductor layer are electrically connected. A semiconductor device characterized by the above.   The semiconductor device according to claim 1, further comprising a second contact made of the second metal formed on the gate wiring.   2. The semiconductor device according to claim 1, wherein the work function of the second metal of the first contact is between 4.0 eV and 4.2 eV.   2. The semiconductor device according to claim 1, wherein a work function of the second metal of the first contact is between 5.0 eV and 5.2 eV.

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