KR19980051072A - Airbridge Inductor and Manufacturing Method - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inductor which is a passive element of a semiconductor device for MMIC, and more particularly, to an air bridge inductor and a method of manufacturing the same, which ensures excellent operating characteristics by minimizing parasitic capacitance on a silicon substrate.

A feature of the present invention is to form an insulating film by applying a silicon oxide film on the silicon substrate (1), so that the upper metal wire 3 and the lower metal wire (4) having the same width so as to be spatially separated from the overlapping part To arrange the lower metal wire 4 of the lower part first, and to apply the oxide film as an insulating film to a predetermined thickness in the following process, and then to arrange the upper metal wire 3 to the upper and lower portions of the opening 6, And forming openings 7 and 11 for electrical contact between the conductive wire 5 and the lower metal wire 4 for electrical connection. And selectively removing the oxide film in a predetermined region (2) corresponding to the spiral portion of the inductor so that the upper metal wire (3) formed in the step can operate as an air bridge inductor. A method of manufacturing an airbridge inductor and an inductor device manufactured by the method.

The air bridge type inductor according to the present invention can be very usefully applied as a passive element in an ultra high frequency integrated circuit.

Description

Airbridge Inductor and Manufacturing Method

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a structure of an inductor, which is a passive element of a semiconductor device for a monolithic microwave integrated circuit (MMIC), which is called a high frequency integrated circuit, and a method of manufacturing the same. The present invention relates to an airbridge type inductor having excellent operating characteristics due to its small parasitic capacitance effect even in a large silicon substrate, and a manufacturing method thereof.

Inductors that have been used in ultra-high frequency integrated circuits (MMIC) are widely known to be manufactured in a spiral shape on a semi-insulating semiconductor substrate or on an insulating film.

In particular, inductors in MMIC semiconductor device manufacturing are one of the required passive components.

The inductors widely used in integrated circuits up to now have a structure in which a spiral metal wire is contacted with a substrate on a semi-insulating compound semiconductor or an insulating film. This inductor structure has no serious problem in use because it has a small parasitic capacitance effect generated between the inductor and the substrate on the semi-insulating substrate or the insulating substrate.

Recently, however, MMIC devices have been used for personal communication systems (PCS) in the 900 MHz band and next generation mobile communication (FPLMTS: future pubic) in the 1.8-2.2 GHz band. The demand for MMIC devices for civil purposes such as this is increasing rapidly. Therefore, it is necessary to secure excellent manufacturing process technology in terms of manufacturing price, performance, size of parts, and so on.

However, MMIC devices manufactured using semi-insulating compound semiconductor substrates have a much higher unit cost than conventional silicon wafer manufacturing process technology. This not only makes semiconductor substrates more expensive than silicon wafers, but also produces smaller sizes of wafers manufactured at the current global level. Because it is lower than silicon.

In addition, as the use of ultra-high frequency devices has been expanded from military purposes to civilian use, the need to produce a large number of ultra-high frequency devices at a lower price is increasing in recent years.

As a result of this trend, MMIC devices using silicon on insulator (SOI) substrates, which can use silicon manufacturing process technology, have been researched and published.

The manufacturing method using an SOI substrate is also manufactured using a separation by implanted oxygen (SIMOX) SOI substrate, and a method using a silicon wafer direct bonding (SDB) SOI wafer by SOI wafer and wafer direct bonding method. All are being studied.

Recently, a technology for manufacturing silicon-based MMIC devices using SOI wafers has been presented at Harris Institute in the United States. However, this fabrication technique is the result of the implementation of passive and active devices on a SOI semiconductor substrate as a microwave semiconductor device operating at about 1 GHz.

In addition, an inductor as a passive device for fabricating a silicon-based MMIC device has been reported to be implemented on a SOI substrate, and its characteristics are superior to that of an inductor manufactured using a conventional silicon wafer.

The air bridge process is widely used in the manufacturing of compound semiconductor integrated circuits, and this technology has been developed during the manufacturing of active devices such as heterojunction bipolar transistors (HBTs) or modulation doped field effect transistors (MODFETs). come. The results of improving the ultrahigh frequency characteristics of semiconductor devices manufactured using the air bridge process have been published.

The manufacturing process of the MMIC device using the compound semiconductor is more complicated than the air bridge process, and the expected improvement in the operating characteristics of the expected MMIC device is not significant. This is because the compound resistivity of the compound semiconductor substrate is much larger than that of the silicon substrate, and thus the result is similar to that of manufacturing an MMIC device in an almost insulated substrate.

An object of the present invention relates to an inductor element and a manufacturing method of a CZ (czochraslsiki) silicon wafer or a SOI wafer using a CZ silicon wafer in which it is difficult to obtain a resistivity value of about 100 Ω-cm or more in particular. The present invention relates to an air carriage type and a method for manufacturing the same, which can secure excellent operating characteristics by minimizing the parasitic capacitance effect of the liver.

Features of the present invention include a method by a double metal wire forming process, a structure of an inductor by a multi-support structure, and a method of manufacturing the same. To fabricate an inductor element by a double metal wire forming process into a structure electrically insulated from a silicon substrate. In order to apply a silicon oxide film with an insulating film, first, in order to make the inductor metal wires in the spirally shaped inductor structure, the inductor metal wires in the overlapping portion of the upper metal wire and the lower metal wire having the same width are separated spatially, In the next process, the oxide film as an insulating film is applied to a predetermined thickness, and then the upper metal wire is disposed, and the upper and lower metal wires are electrically contacted through the openings 6 and 10, and the conductive wires and the lower metal wires are electrically connected. It includes an opening for electrical contact with the airbridge type Air bridge inductor having a structure that selectively removes oxide film in a certain area corresponding to the spiral part of the inductor so as to operate as a ductor, and a method of manufacturing the inductor, and removing a portion except the selected SOI layer to a predetermined thickness After the application of an insulating film (oxide film), a silicon epitaxial film is grown to a little thicker than the thickness of the oxide film through a selective epitaxial film growth process in an opening part of the selected SOI layer, and passes over the oxide film and the epitaxial film thereon. A metal wire having a uniform width is formed, and an SOI layer and a portion of the epitaxial film, which serve as electrical conductors, are formed to operate as an inductor by adding impurities at a high concentration by an ion implantation method. For this purpose, only the insulating film (oxide) in a certain region corresponding to the inductor An air bridge inductor having a multi-support structure in the SOI layer manufactured by the selective etching method, and a heat treatment process for reducing the electrical contact resistance between the metal line and the epitaxial film constituting the inductor Can be characterized.

1 is an exemplary plan view of an air bridge inductor by a double metal line forming process according to the present invention.

2 is a cross-sectional view taken along the line a-a of FIG.

3 is an exemplary plan view of an airbridge inductor having a multi-support structure according to the present invention.

4 is a cross-sectional view taken along the line a-a of FIG.

5A-5E are flowcharts of a manufacturing process of an airbridge inductor having a multi-support structure of the present invention.

* Explanation of symbols for main parts of the drawings

l, 18: silicon substrate 2, 13: inductor region

3: upper metal wire 4: lower metal wire

5: conductor 6, 7, 22: opening part

8, 9, 10, 11, 19, 20: oxide film 12: SOI substrate

14a-14m: epitaxial film 15, 17: metal wire

21: SOI layer 23: electrical connection point

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the air bridge inductor of the present invention and a manufacturing method thereof.

FIG. 1 is an exemplary view of an air bridge inductor by a double metal wire forming process, in which a silicon oxide film is coated with an insulating film to form an inductor element having a structure electrically insulated from the silicon substrate 1, and In the inductor structure, the upper and lower portions of the metal wires 3 and 4 having the same width overlap the upper and lower portions of the metal wires 4 so as to be spatially separated. In the next step carried out, an oxide film as an insulating film is applied to a predetermined thickness, and then the upper metal wire 3 is disposed. The conductive wires 5 for electrically contacting the upper and lower metal wires thus formed through the openings 6 and 7 are provided.

1 illustrates an airbridge inductor having a structure in which an oxide film is selectively removed from a predetermined region 2 corresponding to a spiral portion of an inductor so as to operate as an airbridge inductor. FIG. 2 is a cross-sectional view of a-a 'portion of FIG. 1, wherein the electrical contact between the upper metal wire 3 and the lower metal wire 4 is an opening when the spiral-shaped air bridge inductor is manufactured by a double metal wire forming process. A method of electrical contact with the conductive wire 5 for electrical connection with the lower metal wire 4 through the opening 11 is provided. In particular, in order to enable the inductor to operate in the air bridge type, the inductor structure in which the oxide film in the predetermined region 2 is selectively removed is shown. In the air bridge inductor, the metal wires 3 and 4 constituting the inductor are exposed to the air, and thus the dielectric constant between the upper and lower metal wires 3 and 4 or the upper and lower metal wires 3 and 4 and the silicon substrate are exposed. The constant representing the dielectric constant between (1) has a dielectric constant value in air. That is, the capacitance is inversely proportional to the distance of two plates having a capacitance component and has a relation proportional to the cross-sectional area and dielectric constant of the plate. Therefore, since all the insulators including the semiconductor insulating film have a dielectric constant (ε _r ), the dielectric constant of the capacitance (ε) in the solid-state electronic device is the dielectric constant of the vacuum (ε _o ) and the dielectric constant of the insulator (ε _r ). It is expressed by the product ε _o ε _r . Therefore, since the airbridge type inductor is not a structure in which an insulator is inserted, it is a structure floating in air vapor, so the dielectric constant (ε) of the capacitance has a value similar to ε _o, and this value is equal to the dielectric constant by the ratio of ε _r . Since the size of (ε) is reduced, the total capacitance size is also reduced at the same rate.

A method of manufacturing the airbridge inductor by the double metal line forming process will be described below with reference to FIG. 2.

First, the oxide film 8 is formed to a certain thickness by growing or applying a thermal oxide film as a whole on the silicon substrate 1. At this time, the thickness of the oxide film 8 is a thickness that satisfies the electrical insulation against the operating voltage applied when the inductor is electrically operated, and at the same time, due to the parasitic capacitance between the lower metal wire 4 and the silicon substrate 1. It is necessary to manufacture considering the delay effect of inductor

The next process is a semiconductor integrated circuit fabrication process for forming the lower metal line 4. In this step, the metal film is doped to the entire surface by a sputtering method or a vapor deposition method to a predetermined thickness, and then the remaining portions except for the region selected as the lower metal wire part 4 are removed by the photolithography process to complete the formation of the first step metal wire.

In the next process following the oxide film 9 in order to consider the parasitic capacitance effect occurring between the upper metal line 3 and the lower metal line 4 while maintaining electrical insulation between the upper metal line 3 and the lower metal line 4. Apply on the front.

The thickness of the oxide film 9 minimizes the parasitic capacitance effect generated between the upper metal line 3 and the lower metal line 4, and simultaneously forms the upper metal line 3 and the lower metal line 4 in a single metal line forming process. In order to be able to easily connect the electrical contact through the opening 10, it is necessary to manufacture in the range of thousands of micrometers to 1 micrometer. When the thickness of the oxide film 9 is as small as several hundred micrometers, the process of removing the oxide film 9 between the upper metal wire 3 and the lower metal wire 4 in order to operate in an air bridge type is not easy. Although the parasitic capacitance effect between the and the lower metal wire 4 is increased, the electrical connection through the opening 10 is easy. On the other hand, when the thickness of the oxide film 9 is thick by several micrometers, the process time is long and the cost is increased to form the thick oxide film 9, and the upper metal wire 3 and the lower metal wire 4 are opened with an opening 10 The metallization process for the electrical connection through) is not simple. That is, since the step between the lower metal wire 4 and the upper metal wire 3 is very large, a few micrometers, there is a problem such as using a two-step metal wire forming process. However, for the thick oxide film 9 of several micrometers, the parasitic capacitance in the upper metal wire 3 and the lower metal wire 3 increases because the vertical distance between the upper metal wire 3 and the lower metal wire 4 increases. The effect by is greatly reduced.

The openings 10 and 11 are set as contact points for electrically connecting the lower metal wire 4 and the upper metal wire 3 or the electric conductive wire 5 as the next step after the above step, and the set opening 10 The oxide film 9 in regions (11) and (11) is removed by a photolithography process.

In this case, one of wet etching by chemical solution and dry etching such as reactive ion etching (RIE) may be selected and used as a method of removing the oxide layer 9.

In the case of using the wet etching method, the step of the etching cross section may be smoother than the removal by the dry etching method.

Due to the difference in the above process characteristics, the thicker the thickness of the oxide film at the edge of the etching surface fabricated by the wet etching method, the slower the integration of the inductor device is. Although it is complicated to analyze by the method, etc., since the etching step is relatively slower than the dry etching method, even if the thickness of the oxide film 9 is thick, there is an advantage in the electrical connection through the openings 10 and 11.

After the removal process of the oxide film 9 in the above-described openings 10 and 11 region, in the next step, a metal film is applied to the entire surface to form the upper metal wire 3. At this time, the metal film is applied to the entire surface by sputtering or vapor deposition at a predetermined thickness, and then a method of removing the remaining portions except the region selected as the upper gold lattice (3) by the photolithography process is a two-step metal wire forming process. To complete.

In order to reduce the electrical contact resistance at the openings 10 and 11 for electrical contact, a metal electrode heat treatment process is performed in a nitrogen atmosphere.

In the last step, only the oxide films 8 and 9 except for the metal wires 3 and 4 are wet-etched by using a chemical solution in a certain area 2 including the spiral portion to manufacture an air bridge inductor. Selective etching process is performed.

It is very easy to manufacture air bridge inductor by the above manufacturing method, and it is easy to manufacture air bridge inductor at the same time when manufacturing high frequency integrated circuit because of its excellent connection with existing semiconductor integrated circuit manufacturing process. There is this.

FIG. 3 is an exemplary diagram of an air bridge inductor having a multi-support structure, and FIG. 4 is a partial cross-sectional view of aa 'of FIG. 3 and illustrates a method of configuring an air bridge inductor using the SOI substrate 12. Doing. The remaining portions except for the selected SOIs 16 and 21 are removed, and an insulating film (oxide film) 20 is applied to a predetermined thickness. The epitaxial films 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, and 14k selected from the openings 22 opening part of the selected SOI layer. The epitaxial films are grown to a thickness slightly thicker than the thickness of the oxide film 20 through a selective epitaxial growth process, and the oxide film 20 and the epitaxial films 14a, 14b, and 14c thereon. (14d) (14e) (14f) (14g) (14h) (14i) (14j) (14k) (14l) (14m) to form a metal wire (15) (17) having a uniform width over it. An inductor is constituted by a high concentration of impurities added to the SOI layer 16 and the epitaxial films 14b and 14l, which also function as electrical conductors.

FIG. 4 is a general structure diagram of a multi-support structure air bridge inductor having a structure in which only an insulating film (oxide film) of a predetermined region 13 corresponding to the inductor is removed by a chemical selective etching method in order to manufacture the inductor into an air bridge type. In Fig. 3, the supports made of physics 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, 14k, 14l and 14m are There is an effect of preventing the shaking of the external movement of the metal wire 15 to be floating in the air.

In particular, in FIG. 4, using an SOI substrate including a silicon substrate 18, an oxide film 19, and an SOI 16, 21, an SOI layer 21 and an epitaxial film 14a and 14b used only as a support. Parasitic resistance effect parasitics through the support by making 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, l4k, 14l, 14m at very low resistivity Only the SOI layer 16 and the epitaxial films 14k and 14l having the same effect as reducing the capacitance effect and having a role as an electrical conductor and a support at the same time have very high electrical conductivity. The airbridge type inductor structure is shown to have a high electrical conductivity by an optional manufacturing process method in which high impurities of about 10 ¹⁹ pieces / cm ³ or more are added using impurities.

3 and 4, an optional epitaxial film growth process is essential, and the selective epitaxial films 14a, 14b, 14c, 14d, 14e, 14f, 14g, and 14h are shown. ) (14i) (14j) ( 14k) (14l) (14m) of the heterojunction bipolar transistor, by using a growth process or a silicon germanium bipolar transistor-based (Si _x -Ge ₁₎ (HBT: for very high frequency such as heterojunction bipolar transistor) It is easy to implement the active element in the air bridge type.

Therefore, it is easy to fabricate an ultra-high frequency integrated circuit (MMIC) using silicon substrate materials with excellent operating characteristics, and the epitaxial growth process in the inductor manufacturing process, which is an active element and an air bridge type passive element, is performed in the same process step. This can simplify the production method and achieve economic effects.

In particular, in the air bridge type inductor structure as shown in Figs. 1 and 2, the size of the open capacitance is also simultaneously reduced by the effect of decreasing the size of the dielectric constant ε by the ratio of the ε _r values.

The method of manufacturing the multi-support structure air bridge inductor is performed in the following process sequence.

5A through 5E are flowcharts illustrating a manufacturing process of the multiple support structure air bridge inductor of FIG. 3. 5A shows very high electrical conductivity with respect to the area of the SOI layer 16, which is also used as an electrical conductor, by using an SOI substrate having a silicon substrate 18, an oxide film 19, and an SOI layer 16, 21. FIG. SOI layers (16) and (21) using a photolithography process as a next step in the fixation of ion implantation of boron or phosphorus in a selectively allowed copy using photoresist to make it larger. The process of etching the remaining part leaving the.

In this case, the process for selectively etching only the SOI layers 16 and 2l may be performed by using a dry etching method such as an RIE method, which may effectively remove only the SOI layers 16 and 21 rather than using a wet etching method. The step can be reduced.

In FIG. 5B, the oxide film 20 is applied to the entire surface with a thickness considering the parasitic capacitance effect between the SOI layer 16 and the metal lead 15 used as the electric lead in the air bridge inductor structure, and the selective epitaxial film 14a. 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, 14k, 14l, 14m, openings are opened by a photolithography process to grow them. As a process for removing the oxide film 20, both the etch method and the dry etching method may be used.

However, it is advantageous to use the dry etching method because the etching step of the oxide film 20 can be made more rapid than using the wet etching method.

In FIG. 5C, the epitaxial films 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, 14k, and 14l in the opening region in FIG. Since the height of 14m is lower than the height of the underlayer 20, the end surface of the oxide film 20 has epitaxial films 14a, 14b, 1c, 14d, 1e, 14f, 14g, and 14h. 14i) The silicon epitaxial film grown from the silicon single crystal of the opening opened in FIG. 5B is slightly thicker than the oxide film so as not to form a groove like a groove at the boundary between 14i, 14j, 14k and 14l and 14m. To grow.

This process condition is difficult to analyze the inductor device according to the shape of the metal wires (15) (17) due to the deposition of the metal wires (15) (17) in the grooves, such as grooves in the metal wire forming process of Figure 5d and complicated operation characteristics Can reduce the effect of degradation.

The selective epitaxial growth (SEG) process, which selectively grows silicon epitaxial films that are not added with impurities by an in-situ process, is used for rapid thennal chemical vapor deposition (RTCVD), which is used as a type of vapor deposition. By using SiH ₂ C1 ₂ gas or SiCl ₄ gas containing chlorine as a source gas for growing the silicon epitaxial film, and simultaneously adding HCI gas in a volume ratio of several volume% to the total gas flow rate containing the transport gas. It is carried out by. At this time, the gas concentration in the reactor of the C1 group included in the gas is only on the silicon crystals except for the oxide film 20. It is known to be a major process variable capable of growing 14h, 14i, 14j, 14k, 14l and 14m.

In addition, as a method for improving the electrical conductivity of the epitaxial films 14k and 14l, which simultaneously serve as a support and an electrical conductor after growth of the selective silicon epitaxial film, ion implantation method in a portion selectively allowed using photoresist. In this case, impurities are added at a high concentration, and the impurities are distilled and added at the same level as the SOI layer 16 to which impurities are added with high performance.

In FIG. 5D, after the silicon epitaxial film is grown, a washing process of removing the natural oxide film formed on the silicon surface is performed, followed by the oxide film 20 and the silicon epitaxial films 14a, 14b, 14c, 14d, and 14e. 14f, 14g, 14h, 14i, 14j, 14k, 14l, and 14m are formed.

In order to reduce the contact resistance at the electrical contact point 23 between the silicon epitaxial films 14k and 14l and the metal wires 15 and 17 serving as an electric conductor after the metal wire forming process, the nitrogen atmosphere is subjected to the metal linear process. The heat treatment process is carried out at the appropriate temperature and time conditions for the metal material used. In the gold loss linear process, a predetermined thickness is applied to the entire surface by rf sputtering or vapor deposition, and then a metal line of the inductor is formed by a photolithography process.

In FIG. 5D, it is advantageous to manufacture a metal material having a high melting point and hard tungsten or the like to a predetermined thickness or more in order to reduce the effect of bending or deformation of the metal wires 15 and 17 forming the air bridge.

In FIG. 5E for constructing an airbridge inductor as a final process, after forming a predetermined region 13 corresponding to the inductor of FIG. 3 by a photolithography process to configure the inductor as an airbridge, a metal film in the selected region is selected. In order to remove only the oxide film 20 except the epitaxial film and the SOI layer by a chemical selective etching method, a wet etching method is used, wherein the oxide film 19 under the SOI layers 16 and 21 is formed by using a SIMOX SOI wafer as a substrate. In the case of using the oxide film, the thickness of the oxide film is small, about 2000 GPa, which makes it difficult to etch and mechanically support the SOI layers 16 and 21. A step of partially leaving the oxide film 19 is included.

Since the airbridge inductor based on the two embodiments described above is a structure in which the airbridge inductor is floating in the air chamber instead of the structure in which the insulator is inserted, the dielectric constant of the capacitance ε is similar to ε _o. Since the value of the dielectric constant (ε) decreases by the ratio of ε _r ^{7, the} value of the entire capacitance can also be reduced by the same ratio.

In addition, it is very easy to fabricate an airbridge inductor by a manufacturing method using a double metal wire forming process, and the airbridge inductor can be used when manufacturing an ultrahigh frequency integrated circuit because of its excellent connection with a conventional semiconductor integrated circuit manufacturing process. At the same time, it is easy to manufacture.

Epitaxial films 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, 14k, 14l, 14m in an airbridge inductor with a multi-support structure. The support made of) has the effect of preventing the shaking of the external movement of the metal wire (15) floating in the air.

In particular, in FIG. 4, using an SOI substrate including a silicon substrate 18, an oxide film 19, and an SOI layer 16, 21, an SOI layer 21 and an epitaxial film 14a (used only as a support base) ( Parasitic resistance effect through the support by making 14b) 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, 14k, 14l and 14m at very low specific resistance. And the parasitic capacitance effect can be greatly reduced.

Selective epitaxial film growth process is essential for the airbridge type inductor device structure, and the selective epitaxial films 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, and 14i 14j) (14k) (14l) (14m) by using a growth step bipolar transistor or silicon germanium-based (Si ₁ - heterojunction bipolar transfected sister (HBT of _k Ge _k): neungdeung element for the very high frequency such as heterojunctlon bipolar translstor) Fig. Since it is easy to implement in an air bridge type, it is very advantageous to manufacture an ultra-high frequency integrated circuit (MMIC) having excellent operating characteristics by using a silicon substrate material. Since the epitaxial growth process can be carried out in the same process step, the production method is simplified and economical effect is also obtained. In addition, openings are formed to grow selective epitaxial films 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, 14k, 14l, and 14m. A photolithography process is used to remove the oxide film 20 in the opening, and the dry etching method is used. Therefore, the etching step of the oxide film 20 can be made more rapidly than that of the wet etching method. have.

Claims (4)

An oxide film 8 is formed on the silicon substrate 1, a lower metal line 4 is formed on the oxide film, an insulating film 9 is formed on the lower metal line 4, and then a spiral shape is formed thereon. The upper metal wire 3 and the conductive wire 5 are separately formed, and one side of the upper metal wire 3 and the lower metal wire 4 is connected through the opening 6, and the other side of the lower metal wire 4 is opened. 7) Air bridge type inductor, characterized in that formed by connecting through. In the method of manufacturing an inductor device using a double metal wire, the step of forming an insulating film by applying a silicon oxide film on the silicon substrate 1, the portion where the upper metal wire 3 and the lower metal wire 4 having the same width up and down overlap Placing the lower metal wire 4 at the lower portion so as to be spatially separated from the substrate, applying the oxide film as an insulating film to a predetermined thickness in the following process, and then disposing the upper metal wire 3 at the upper and lower metal wires. The openings 6 and 10 are formed to be in electrical contact with the metal, and the openings 7 and 11 are electrically connected to the conductive wire 5 and the lower metal wire 4 for electrical connection. Forming and performing a metallic process, and selectively selecting an oxide film in a predetermined region (2) corresponding to the spiral portion of the inductor so that the upper metal wire (3) formed in the step can operate as an air bridge inductor. Method of manufacturing an air bridge inductor comprising the step of removing. 3. The method of manufacturing an airbridge inductor according to claim 2, wherein the thickness of the electrically insulating oxide film (90) between the upper metal wire (3) and the lower metal wire (4) is formed to be 1000 m to 1 micrometer. In the method of manufacturing an air bridge inductor having a multi-support structure, after removing the remaining portions except the selected SOI layer (16), (21), applying an insulating film (oxide) 20 to a predetermined thickness, and Selective epitaxial films 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i, 14j, and 14k in the openings 22 that open part of the SOI layer. Growing a silicon epitaxial film to a thickness slightly thicker than the thickness of the oxide film 20 through a growth process of 14l) (14m), and over the epitaxial film, the oxide film 20 and the epitaxial films 14a, 14b and 14c ( Forming metal wires 15 and 17 having uniform widths over 14d) 14e, 14f, 14g, 14h, 14i, 14j, 14k, 14l, and 14m; and And adding the impurities in a high concentration to the SOI layer 16, the epitaxial films 14b, 14l by the ion implantation method, which also acts as an electrical conductor, to give a function as an inductor, Bridge bridge To remove only the insulating film (oxide film) of the predetermined region 13 corresponding to the inductor by a chemical selective etching method, and to reduce the electrical contact resistance between the metal wire and the epitaxial film constituting the air-bridge inductor of the multi-support structure Method for manufacturing a multi-support structure air bridge type inductor comprising a heat treatment step for.