JP2009064969A - Semiconductor device, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a schottky barrier diode capable of expressing a forward characteristic and a backward characteristic according to use application in spite of having one type of schottky metal. <P>SOLUTION: This semiconductor device is fabricated by forming a schottky junction region with a semiconductor substrate 1 having a first conductivity type semiconductor layer 2 on a surface, a guard ring 6 comprising a second conductivity type semiconductor region extending into a layer from a surface of the semiconductor layer 2, and a metal layer 4 formed on the semiconductor layer surface surrounded by the guard ring 6. The schottky junction region includes: an eutectic region 7 having an eutectic layer formed between the metal layer 4 and the semiconductor layer 2; and an eutectic region surrounded by the eutectic region 7, having an insulation film pattern 5 interposed between the metal layer 4 and the semiconductor layer 2, and having an eutectic thickness smaller than that of the eutectic region. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a semiconductor device and a method for manufacturing the same, and particularly provides a Schottky barrier semiconductor device that exhibits forward characteristics and reverse characteristics according to usage.

  Conventionally, two types of Schottky barrier diodes are formed using two types of Schottky barriers as a Schottky barrier type semiconductor device using rectification characteristics by Schottky junction, and the areas of these two types of Schottky barrier diodes are formed. There is a device that provides a Schottky barrier semiconductor device having forward characteristics and reverse characteristics according to the intended use by appropriately adjusting and connecting them in parallel (for example, see Patent Document 1). FIG. 9A shows a plan view of a conventional Schottky barrier semiconductor device described in Patent Document 1, and FIG. 9B shows a cross-sectional view.

  In this semiconductor device, as shown in FIGS. 9A and 9B, a first Schottky barrier diode D1 and a second Schottky barrier diode D2 are formed on the same substrate. Here, a low-concentration N-type semiconductor layer 102 is formed on an N-type semiconductor substrate 101, and a first Schottky barrier diode D1 and a second Schottky barrier diode are formed on the surface portion of the low-concentration N-type semiconductor layer 102. Guard rings 106 made of P-type semiconductor regions surrounding the portions forming D 2 are formed, and oxide films 103 are formed along the guard rings 106 on the surface portions of the guard rings 106, and are surrounded by the oxide films 103. The first Schottky metal 104S and the second Schottky metal 104 are stacked in the two regions. By changing the area ratio of the first Schottky barrier diode D1 and the second Schottky barrier diode D2 and the type of the first Schottky metal 104S and the second Schottky metal 104, the forward direction according to the intended use A Schottky barrier semiconductor device that exhibits characteristics and reverse characteristics is provided.

JP 2004-103853 A

However, the apparatus configuration requires two types of Schottky metal and must be formed in a separate process, which has a problem that the process becomes complicated.
In addition to semiconductor devices equipped with a plurality of Schottky barrier diodes, a Schottky metal must be selected in order to obtain a desired barrier height in discrete Schottky barrier diodes. There has been a demand for a semiconductor device structure capable of obtaining desired characteristics without changing the above.

The present invention has been made in view of the above circumstances, and a semiconductor device including a Schottky barrier diode that exhibits forward characteristics and reverse characteristics in accordance with the intended use using one kind of Schottky metal, and its manufacture It aims to provide a method.
In addition, the present invention includes a Schottky barrier diode that can obtain a desired barrier height according to the intended use without changing the Schottky metal material to be used, and exhibits desired forward characteristics and reverse characteristics. An object of the present invention is to provide a semiconductor device and a manufacturing method thereof.

Accordingly, a Schottky barrier type semiconductor device of the present invention is a guard comprising a semiconductor substrate having a first conductivity type semiconductor layer on its surface and a second conductivity type semiconductor region extending from the surface of the semiconductor layer into the layer. A semiconductor device in which a Schottky junction region is formed by a ring layer, the semiconductor layer surface surrounded by the guard ring, and a metal layer formed on the semiconductor layer surface, wherein the Schottky junction region is A eutectic region in which a eutectic layer is formed between the metal layer and the semiconductor layer, and an insulating film pattern is interposed between the metal layer and the semiconductor layer, and is surrounded by the eutectic region. And an inter-eutectic region having a eutectic thickness smaller than that of the crystal region.
If an insulating film is present in the vicinity of the eutectic layer, the outermost electrons in the eutectic layer are attracted to the insulating film and stabilized. Therefore, the barrier height in the vicinity of the insulating film is higher than other portions. Therefore, when the area of the insulating film is large, characteristics with high barrier height are exhibited, and when the area of the insulating film is small, characteristics with low barrier height are exhibited. Thus, since the energy of the outermost shell electrons of the eutectic layer existing in the vicinity of the second insulating film changes under the influence of the atoms constituting the second insulating film, the barrier height at the same location is This is different from the barrier height of the eutectic layer located away from the two insulating films. Therefore, by changing the pitch (area) in which the second insulating film is present, the barrier height is adjusted, and a semiconductor device that exhibits forward characteristics and reverse characteristics according to the intended use can be obtained. Here, when the second insulating film does not exist as long as the atoms constituting the second insulating film are atoms having an electronegativity large enough to attract the outermost electrons of the eutectic layer, In addition to oxygen and nitrogen, carbon, sulfur, boron, phosphorus, etc. are effective.

Further, the present invention includes the semiconductor device, wherein the eutectic layer is formed so as to be connected under the insulating film pattern.
With this configuration, the barrier height can be adjusted without substantially reducing the area of the current path in the Schottky junction region.

  According to the present invention, in the semiconductor device described above, an annular first insulating film is formed on the surface of the semiconductor layer so as to cover a part of the guard ring layer, and the surface of the semiconductor layer in the Schottky junction region Includes those in which the insulating film pattern made of the second insulating film is formed.

According to the present invention, in the semiconductor device, the insulating film pattern includes a width smaller than several hundred nm.
If the width of the insulating film pattern exceeds several hundreds of nanometers in width, there is a problem that the electric field under the insulating film pattern becomes strong and the leakage current increases when reverse bias is applied. It is desirable not to exceed.

  According to the present invention, in the semiconductor device, the second insulating film includes an oxygen atom.

  According to the present invention, in the semiconductor device, the second insulating film includes a nitrogen atom.

  According to the present invention, in the semiconductor device, the second insulating film includes an oxygen atom and a nitrogen atom.

  The present invention includes the above semiconductor device including a Schottky barrier diode having the Schottky junction as a circuit element.

  According to the present invention, in the semiconductor device, the semiconductor integrated circuit includes a MOSFET as a circuit element.

  According to the present invention, in the above semiconductor device, the first Schottky barrier diode and the second Schottky barrier diode are provided, and the metal constituting the Schottky junction surface of the first and second Schottky barrier diodes is provided. And the second insulating film on the Schottky junction surface of the first Schottky barrier diode is the same as the second insulating film on the Schottky junction surface of the second Schottky barrier diode. Includes those having different pattern pitches.

  According to the present invention, in the semiconductor device, the metal layer includes a Schottky metal layer including any of nickel, molybdenum, and titanium and an electrode layer including aluminum.

  According to another aspect of the present invention, there is provided a step of preparing a semiconductor substrate having a first conductivity type semiconductor layer on a surface thereof, and forming a guard ring layer comprising a second conductivity type semiconductor region extending from the surface of the semiconductor layer into the layer. A method of manufacturing a semiconductor device, comprising: a step; and a step of forming a Schottky junction between the surface of the semiconductor layer surrounded by the guard ring and a metal layer formed on the surface of the semiconductor layer, Forming an insulating film pattern having a width of several to several hundreds nm on the surface of the semiconductor layer, forming a metal layer, and eutectic reaction between the metal layer and the semiconductor layer. And a step of forming a eutectic layer.

  According to the present invention, in the method of manufacturing a semiconductor device, the step of forming the eutectic layer includes a step of performing heat treatment so that the eutectic layer is connected under the insulating film pattern.

  According to the present invention, in the method of manufacturing a semiconductor device, a step of forming a first conductivity type semiconductor layer having a concentration lower than that of the semiconductor substrate by epitaxial growth on the first conductivity type semiconductor substrate; Forming a first insulating film on the first insulating film; forming an opening in the first insulating film corresponding to a guard ring formation planned region; exposing the semiconductor layer; and exposing the surface of the exposed semiconductor layer. Implanting impurities of the second conductivity type to form a guard ring layer extending annularly from the surface of the semiconductor layer into the layer, and an annular covering from the periphery of the semiconductor layer to a part of the guard ring layer The first insulating film is left so as to constitute the pattern, and the first insulating film in other portions is selectively removed and the first insulating film is removed by the step of removing the first insulating film. Of the semiconductor layer Forming a second insulating film having a width of several nanometers to several hundreds of nanometers on the surface and the surface of the guard ring layer; forming a metal layer on the surface of the semiconductor layer and the surface of the guard ring layer; And a eutectic layer forming step of forming a eutectic layer of the semiconductor layer and the guard ring layer and the metal layer by heat treatment.

  According to the present invention, in the method of manufacturing a semiconductor device, the step of forming the second insulating film includes a step of forming an insulating film by a CVD method and patterning by photolithography.

  According to the present invention, in the semiconductor device manufacturing method, the step of forming the second insulating film includes a step of forming a silicon oxide film.

  According to the present invention, in the method for manufacturing a semiconductor device, the step of forming the second insulating film includes a step of forming a silicon nitride film.

  According to the present invention, in the method of manufacturing a semiconductor device, the step of forming the second insulating film includes a step of forming a silicon oxynitride film.

  According to the present invention, in the semiconductor device manufacturing method, a semiconductor integrated circuit is configured using the Schottky barrier diode having the Schottky junction as a circuit element, and a metal layer used in the semiconductor integrated circuit is used. Before the formation of the metal layer, the step of determining the size and density of the insulating film pattern so that the barrier height (barrier height) of the Schottky junction in the Schottky barrier diode becomes a desired value, Forming an insulating film pattern so as to have a desired barrier height in the semiconductor integrated circuit.

  The present invention also provides a method for manufacturing a semiconductor device, comprising: a plurality of Schottky barrier diodes, wherein a Schottky barrier barrier height (barrier height) in the Schottky barrier diode is a desired value. Determining the size and density of the insulating film pattern for each diode; and prior to the formation of the metal layer, the size or density of the insulating film pattern so as to have a desired barrier height in the semiconductor integrated circuit. Forming different insulating film patterns.

  According to the present invention, in the method for manufacturing a semiconductor device, the step of forming the metal layer includes a step of forming a Schottky metal layer including any of nickel, molybdenum, and titanium, and an electrode layer including aluminum. Process.

  As described above, according to the present invention, while using the same metal layer (Schottky metal), the barrier height can be adjusted, and the Schottky that expresses the forward characteristics and the reverse characteristics according to the intended use. It becomes possible to provide a barrier semiconductor device and a manufacturing method thereof.

  In a semiconductor integrated circuit, a MOS and an ohmic junction with a semiconductor layer and a Schottky junction with a semiconductor layer may be formed simultaneously in a single metal lamination process. In the conventional technique, the barrier height of the Schottky junction formed simultaneously has to be equal, but a desired barrier height can be easily obtained only by adjusting the pattern of the insulating film interposed between the semiconductor layer and the metal layer. be able to.

  When the technology of the semiconductor device of the present invention is applied to a semiconductor integrated circuit, a plurality of Schottky junctions constituting the integrated circuit can each have a unique barrier height. There is a strong demand for controlling the barrier height of a Schottky junction in a composite element of a CMOS and a Schottky barrier semiconductor device among integrated circuits, and the present invention can meet this demand.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
As shown in FIGS. 1A and 1B, the Schottky barrier diode as the semiconductor device in the first embodiment of the present invention is intermittently provided between the metal layer forming the Schottky junction and the semiconductor layer. An insulating film pattern with a width of several nanometers to several hundreds of nanometers is arranged, and a region other than the insulating film pattern is formed with a eutectic layer, and by changing a pitch (area) at which the insulating film exists, It is characterized by adjusting the barrier height. FIG. 1A shows a cross section of the Schottky barrier diode, and FIG. 1B is a top view of the state in which the Schottky metal is removed as viewed from above.

  As shown in FIG. 1, the Schottky barrier diode includes an N-type silicon substrate having an N− type silicon layer 2 on the surface as a first conductivity type semiconductor layer, and an N− type silicon layer 2. Guard ring layer 6 composed of a P-type silicon region extending from the surface into the layer, N-type silicon layer 2 surrounded by guard ring layer 6, and metal formed on the surface of N-type silicon layer 2 A semiconductor device in which a Schottky junction is formed with a molybdenum layer which is a layer 4, and an oxide having a width of several nm to several hundred nm is intermittently provided between the metal layer 4 and the N− type silicon layer 2. An insulating film pattern made of a silicon film is arranged, and a region other than the insulating film pattern 5 is formed with a molybdenum silicide layer as the eutectic layer 7. Here, the width of the insulating film pattern 5 is set to several nanometers to several hundred nanometers because the size that can be formed in consideration of the resolution limit is from several nanometers. There is an inconvenience that the region that is not formed becomes too large and the resistance of the junction region becomes high.

According to such a configuration, the energy of the outermost electrons of the eutectic layer existing in the vicinity of the insulating film changes under the influence of the atoms constituting the insulating film, so that the barrier height at the same location is This is different from the barrier height of the eutectic layer at a distance from Therefore, by changing the interval and width (size) of the insulating film, and thus the area ratio, it is possible to adjust the barrier height and obtain a semiconductor device that exhibits forward characteristics and reverse characteristics according to the intended use. Is.
In this way, as the area where the insulating film pattern 5 exists is increased, a Schottky barrier semiconductor device with lower leakage can be obtained.

Next, a method for manufacturing such a Schottky barrier diode will be described. This will be described with reference to FIGS.
2 and 3 show cross sections at the end of the main steps of the manufacturing process of the Schottky barrier diode according to the embodiment of the present invention, where 1 is an N-type silicon substrate, 2 is a low concentration N-type silicon layer, 3 Is a first insulating film covering the periphery including the P-type guard ring layer 6, 4 is a metal film such as molybdenum forming a Schottky junction, 5 is a pattern of the second insulating film, 7 is an N-type silicon layer A molybdenum silicide layer that is a eutectic layer with a Schottky metal as the metal film 4 is shown.

  First, as shown in FIG. 2A, a low-concentration N− type silicon layer 2 is formed on an N type silicon substrate 1 by epitaxial growth, and a thermal oxidation method is formed on the N− type silicon layer 2. A silicon oxide film is formed to form the first insulating film 3 (initial oxidation step).

  Next, as shown in FIG. 2B, after the initial oxidation step, the first insulating film 3 located above the portion where the P-type guard ring layer is to be formed is removed by etching to remove the low-concentration N-type silicon layer 2. To expose the surface (window opening process).

  Thereafter, as shown in FIG. 2 (c), boron, which is a P-type dopant, is implanted into the surface of the N-type silicon layer 2 exposed after the window opening process using the first insulating film 3 as a mask to perform thermal diffusion. The P-type guard ring layer 6 extending annularly from the surface of the N-type silicon layer 2 into the N-type silicon layer 2 is formed by drive diffusion by the method, and the N-type silicon substrate 1 and the low concentration N- A semiconductor substrate S composed of a p-type silicon layer 2 and a p-type guard ring layer 6 is formed (P-type guard ring layer forming step).

  Next, as shown in FIG. 3A, an annular first insulating film 3 covering the periphery of the substrate formed on the first main surface of the semiconductor substrate S to a part of the P-type guard ring layer 6. The other portions of the first insulating film 3 are selectively removed by etching to expose the surface of the N− type silicon layer 2 and the surface of the P type guard ring layer 6 (first insulating film removal). Process).

  Next, as shown in FIG. 3B, the second surface is exposed to the surface of the N-type silicon layer 2 and the surface of the P-type guard ring layer 6 exposed in the first insulating film removal step by heat treatment or CVD. The insulating film 5 is formed, and the second insulating film 5 in other portions is removed by etching while leaving the plurality of second insulating films 5 having a width of several nm to several hundred nm (second insulating film forming step). ).

  Then, as shown in FIG. 3C, the surface of the plurality of second insulating films 5 and the N− type silicon layer 2 surrounded by the first insulating film 3 and the P-type guard ring by vapor deposition or sputtering. A molybdenum layer is laminated as a metal layer 4 covering the surface of the layer 6 and extending to the periphery of the first insulating film 3 (Schottky metal forming step).

  And finally, as shown in FIG.3 (d), the eutectic layer 7 of the low concentration N <-> type | mold silicon layer 2 and the P type guard ring layer 6, and the metal layer 4 is formed by heat processing (eutectic layer formation). Process). FIG. 4 is an enlarged view of a main part thereof, and the barrier height changes depending on the interval and size of the second insulating film pattern 5 as shown in the band diagram of FIG. The width (size) of the second insulating film pattern 5 may be heat-treated so that the eutectic layer is connected under the insulating film pattern by heat treatment in the eutectic layer forming step.

  Although the present embodiment has been described on the assumption that a plurality of second insulating film patterns 5 are formed in parallel as an insulating film interposed between the N− type silicon layer 2 and the metal layer 4, The present invention is not limited to this, and as shown in a modified example in FIG. With respect to the width of the second insulating film pattern, heat treatment may be performed so that the eutectic layer is connected under the insulating film pattern by heat treatment.

  In the present embodiment, the first conductivity type is N-type and the second conductivity type is P-type. However, the present invention is not limited to this, and both may be reversed. In that case, the anode and cathode are also reversed.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. In the present embodiment, as shown in FIG. 7, the first and second Schottky barrier diodes D1 and D2 are semiconductor integrated circuits formed on the same substrate, and the same metal layer 4 is used while the first metal layer 4 is used. The one Schottky barrier diode D1 is formed to have a higher barrier height than the second Schottky barrier diode D2. The metal layer 4 constituting the Schottky junction surface of the first and second Schottky barrier diodes is the same metal layer (molybdenum), and the second Schottky junction surface of the first Schottky barrier diode is the second. The insulating film has a larger pattern pitch than the second insulating film on the Schottky junction surface of the second Schottky barrier diode.
According to this configuration, two types of Schottky barriers can be obtained with the same metal layer, so that the number of steps can be reduced by forming and patterning the metal layer only once.

(Embodiment 3)
Next, a third embodiment of the present invention will be described. In the present embodiment, as shown in FIG. 8, the Schottky barrier diode D and the trench MOSFET (MOS) are semiconductor integrated circuits formed on the same substrate, and the same metal layer 4 is used while the first metal layer 4 is used. The Schottky junction of one Schottky barrier diode D and the ohmic junction of the trench MOSFET are formed well. The metal layer 4 constituting the Schottky junction surface of this Schottky barrier diode and the electrode of the trench MOSFET are made of the same metal layer (molybdenum).

The Schottky barrier diode D is the same as in the first and second embodiments, and the description thereof is omitted. However, the MOSFET is on the drain region 11 composed of an N-type epitaxial growth layer formed on the N-type silicon substrate 1. In addition, a P-type region 14 and an N ⁺ -type source region 13 formed on the surface of the P-type region 14 are configured. A trench T that penetrates the source region 13 and the P-type region 14 and reaches the upper portion of the drain region 11 is provided, and a vertical gate electrode 20 made of doped polysilicon is embedded in the trench T. Yes. The uppermost surface of the vertical gate electrode 20 is formed to be located a predetermined depth below the surface of the epitaxial layer where the source region 13 exists. An insulating film 30 is filled on the upper side of the vertical gate electrode 20 in the trench T. A silicon oxide film 40 serving as a gate insulating film is interposed between the vertical gate electrode 20 and the surface serving as the vertical wall surface of the trench in each of the drain region 11 and the P-type region 14. . On the epitaxial layer E, an electrode made of the metal layer 4 connected to the source region 13 is provided.
According to this configuration, a Schottky barrier having a desired barrier height can be obtained with the same metal layer as the source wiring of the MOSFET, so that the number of steps can be reduced by forming and patterning the metal layer only once. it can.

  It is useful as a Schottky barrier diode and a semiconductor integrated circuit using the same, and can be applied to various devices such as a DCDC power supply circuit because it is suitable for developing a forward characteristic and a reverse characteristic according to the intended use. It is.

Sectional drawing and top view of Schottky barrier diode in Embodiment 1 of this invention Manufacturing process diagram of the Schottky barrier diode Manufacturing process diagram of the Schottky barrier diode Explanatory drawing of the principal part of the Schottky barrier diode in Embodiment 1 of this invention Explanatory drawing of the principle of the Schottky barrier diode in Embodiment 1 of this invention The figure which shows the modification of embodiment of this invention Sectional drawing and top view which show the semiconductor device in Embodiment 2 of this invention Sectional drawing and top view which show the semiconductor device in Embodiment 3 of this invention Sectional view of a conventional Schottky barrier semiconductor device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 N type semiconductor substrate 2 Low concentration N type semiconductor layer 3 First insulating film 4 Metal layer 5 Second insulating film 6 P type guard ring layer 7 Eutectic layer S Semiconductor substrate D1 First Schottky barrier diode D2 First Second Schottky barrier diode 101 N-type semiconductor substrate 102 Low-concentration N-type semiconductor layer 103 Oxide film 104 First Schottky metal 104s Second Schottky metal 105 Surface electrode metal 106 P-type semiconductor region 108 Back electrode metal

Claims (21)

A semiconductor substrate provided with a semiconductor layer of a first conductivity type on the surface;
A guard ring layer comprising a semiconductor region of a second conductivity type extending from the surface of the semiconductor layer into the layer;
A semiconductor device in which a Schottky junction region is formed by a surface of the semiconductor layer surrounded by the guard ring and a metal layer formed on the surface of the semiconductor layer,
The Schottky junction region is surrounded by a eutectic region in which a eutectic layer is formed between the metal layer and the semiconductor layer, and an insulating film between the metal layer and the semiconductor layer. A semiconductor device including an inter-eutectic region having a pattern and a thinner eutectic thickness than the eutectic region. The semiconductor device according to claim 1,
The eutectic layer is a semiconductor device formed to be connected under the insulating film pattern. The semiconductor device according to claim 1, wherein
On the surface of the semiconductor layer, an annular first insulating film that covers a part of the guard ring layer is formed,
A semiconductor device in which the insulating film pattern made of a second insulating film is formed on the surface of the semiconductor layer in the Schottky junction region. A semiconductor device according to any one of claims 1 to 3,
The insulating film pattern is a semiconductor device having a width smaller than several hundred nm. The semiconductor device according to claim 1,
The second insulating film is a semiconductor device containing oxygen atoms. The semiconductor device according to claim 1,
The second insulating film is a semiconductor device containing nitrogen atoms. The semiconductor device according to claim 1,
The second insulating film is a semiconductor device containing oxygen atoms and nitrogen atoms. A semiconductor device according to claim 1,
A semiconductor device comprising a semiconductor integrated circuit including a Schottky barrier diode having the Schottky junction as a circuit element. The semiconductor device according to claim 8,
The semiconductor integrated circuit is a semiconductor device including a MOSFET as a circuit element. A semiconductor device according to claim 8 or 9, wherein
Comprising a first Schottky barrier diode and a second Schottky barrier diode;
The metal layers constituting the Schottky junction regions of the first and second Schottky barrier diodes are the same metal layer,
The second insulating film in the Schottky junction region of the first Schottky barrier diode is a semiconductor device having a pattern pitch different from that of the second insulating film in the Schottky junction region of the second Schottky barrier diode. A semiconductor device according to claim 1,
The metal layer is a semiconductor device including a Schottky metal layer containing any of nickel, molybdenum, and titanium and an electrode layer containing aluminum. Preparing a semiconductor substrate having a first conductivity type semiconductor layer on its surface;
Forming a guard ring layer comprising a semiconductor region of a second conductivity type extending from the surface of the semiconductor layer into the layer;
A method of manufacturing a semiconductor device, including a step of forming a Schottky junction between the surface of the semiconductor layer surrounded by the guard ring and a metal layer formed on the surface of the semiconductor layer,
Forming the Schottky junction;
Forming an insulating film pattern on the surface of the semiconductor layer;
Forming a metal layer;
Forming a eutectic layer by a eutectic reaction between the metal layer and the semiconductor layer,
A eutectic region in which a eutectic layer is formed between the metal layer and the semiconductor layer; and an eutectic region surrounded by the eutectic region, and an insulating film pattern interposed between the metal layer and the semiconductor layer, A method for manufacturing a semiconductor device, comprising: an intereutectic region having a eutectic thickness smaller than that of the eutectic region. A method of manufacturing a semiconductor device according to claim 12,
The step of forming the eutectic layer is a method of manufacturing a semiconductor device, which is a step of performing heat treatment so that the eutectic layer is connected under the insulating film pattern. A method of manufacturing a semiconductor device according to claim 12 or 13,
Forming a first conductivity type semiconductor layer having a concentration lower than that of the semiconductor substrate by epitaxial growth on the first conductivity type semiconductor substrate;
Forming a first insulating film on the semiconductor layer;
Forming a window corresponding to a guard ring formation scheduled region in the first insulating film, and exposing the semiconductor layer; and
Injecting a second conductivity type impurity into the exposed semiconductor layer surface to form a guard ring layer extending annularly from the surface of the semiconductor layer into the layer;
The first insulating film is selectively removed while leaving the first insulating film so as to form an annular pattern covering the periphery of the semiconductor layer to a part of the guard ring layer. Process,
Forming a second insulating film having a width of several to several hundred nm on the surface of the semiconductor layer exposed by the step of removing the first insulating film and the surface of the guard ring layer;
Forming a metal layer on the surface of the semiconductor layer and the surface of the guard ring layer;
And a eutectic layer forming step of forming a eutectic layer of the semiconductor layer and the guard ring layer and the metal layer by heat treatment. A method for manufacturing a semiconductor device according to claim 12, comprising:
The step of forming the second insulating film is a method of manufacturing a semiconductor device, which is a step of forming an insulating film by a CVD method and patterning by a photolithography. A method for manufacturing a semiconductor device according to claim 12, comprising:
The method of manufacturing a semiconductor device, wherein the step of forming the second insulating film is a step of forming a silicon oxide film. A method for manufacturing a semiconductor device according to claim 12, comprising:
The method of manufacturing a semiconductor device, wherein the step of forming the second insulating film is a step of forming a silicon nitride film. A method for manufacturing a semiconductor device according to claim 12, comprising:
The method of manufacturing a semiconductor device, wherein the step of forming the second insulating film is a step of forming a silicon oxynitride film. A method for manufacturing a semiconductor device according to claim 12, comprising:
A semiconductor integrated circuit is configured with a Schottky barrier diode having the Schottky junction as a circuit element,
Using the metal layer used in the semiconductor integrated circuit, the size and density of the insulating film pattern are determined so that the barrier height (barrier height) of the Schottky junction in the Schottky barrier diode becomes a desired value. And a process of
Forming a dielectric film pattern so as to have a desired barrier height in the semiconductor integrated circuit prior to forming the metal layer. A method of manufacturing a semiconductor device according to any one of claims 12 to 19,
A plurality of Schottky barrier diodes are included, and the size and density of the insulating film pattern are set for each Schottky barrier diode so that the barrier height (barrier height) of the Schottky junction in the Schottky barrier diode becomes a desired value. A step of determining;
Forming an insulating film pattern having a different size or density of the insulating film pattern so as to have a desired barrier height in the semiconductor integrated circuit prior to forming the metal layer. A method for manufacturing a semiconductor device according to any one of claims 12 to 20,
The step of forming the metal layer includes a step of forming a Schottky metal layer containing any of nickel, molybdenum, and titanium and a step of forming an electrode layer containing aluminum.

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