JP3497221B2 - LC element, semiconductor device and method of manufacturing LC element - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LC element, a semiconductor device and a method for manufacturing an LC element, which can be incorporated in a semiconductor device or the like or can attenuate a predetermined frequency band by itself.

[0002]

2. Description of the Related Art With the development of electronic technology in recent years, electronic circuits have been widely used in various fields. Therefore, it is desirable to operate these electronic circuits stably and reliably without being affected by the outside. Be done.

However, noise enters the electronic circuit directly or indirectly from the outside. For this reason,
There is a problem that various electronic devices using electronic circuits often cause malfunctions.

In particular, electronic circuits often use a switching regulator as a DC power source. Therefore, a large amount of noise having various frequency components is often generated in the power supply line of the switching regulator due to a transient current such as switching or due to a load change caused by the switching operation of the digital IC used. Then, these noises are propagated to other circuits in the same device through the power supply line or by radiation to cause malfunction or S / S.
This may have a bad effect such as a decrease in N ratio, and may cause malfunction of other electronic devices that are being used even closer.

In order to remove such noise, various noise filters are generally used in electronic circuits.
In particular, since many electronic devices with various configurations are used in recent years, regulations on noise have become more and more stringent, and as a small, high-performance noise filter that can reliably remove generated noise. Development of a functional LC element is desired.

As one of such LC elements, the LC noise filter disclosed in Japanese Patent Laid-Open No. 3-259608 is known. This LC noise filter has an L component and a C component in a distributed constant, and can obtain good attenuation characteristics over a relatively wide band as compared with a lumped constant type LC noise filter. is there.

[0007]

By the way, the above-mentioned L
The C noise filter is manufactured by forming a capacitor conductor on one surface of an insulating sheet and an inductor conductor on the other surface, and then folding the insulating sheet. However, there is a problem that the manufacturing process becomes complicated because such processes are required.

Also, this LC noise filter is used as an IC or L
When the SI power supply line or the signal line is directly inserted and used, the LC noise filter and the IC or the like must be wired, and there is a problem that it takes time to assemble the components.

Further, since this LC noise filter is formed as a single component, there is a problem that it is almost impossible to include it in an IC or LSI circuit, that is, to insert it in an internal conduit of the IC or LSI. there were.

Further, the capacitance of the capacitor and the resistance of each conductor formed in a distributed constant in this LC noise filter are determined by the respective shapes and arrangements of the conductor for inductors and the conductor for capacitors. After completion, the capacitance and resistance became constant, and the characteristics as a whole were fixed, so there was the problem of not being versatile. For example, if you want to change the capacitance or resistance, you need to change the shape of the conductor for inductors or the conductor for capacitors, and change the capacitance or resistance as needed in the built-in circuit before use. It is difficult.

Therefore, the present invention was created in view of the above-mentioned points, and its purpose is to simplify the manufacturing process and to eliminate the work of assembling parts in the subsequent steps, and further to realize the IC and LSI. An object of the present invention is to provide an LC element that can be formed as a part, a semiconductor device, and a method for manufacturing the LC element.

Another object of the present invention is to provide an LC element whose characteristics can be arbitrarily changed by changing the capacitance or resistance existing in a distributed constant as necessary.
It is to provide a method for manufacturing a semiconductor device and an LC element.

[0013]

(1) In order to solve the above-mentioned problems, the LC element of the present invention is formed on a semiconductor substrate and has a first non-spiral shape which functions as a gate.
A second electrode of non-spiral shape formed on the semiconductor substrate adjacent to the first electrode,
Said first electrode, said insulating layer formed between the semiconductor substrate, in the said semiconductor substrate, a source is formed at both ends of the channel formed in correspondence to the first electrode and A drain, a inductor formed by each of the channel formed corresponding to the first electrode and the second electrode, and a capacitor formed between them exist in a distributed constant manner. , At least a channel formed corresponding to the first electrode is used as a signal input / output path.

(2) The LC element of the present invention is formed on a semiconductor substrate and has a non-spiral-shaped first electrode functioning as a gate and a first electrode on the semiconductor substrate adjacent to the first electrode. a second electrode of the non-spiral shape formed, the first electrode, an insulating layer formed between said semiconductor substrate, in the said semiconductor substrate, said first
A source or drain formed at one end of a channel formed corresponding to the electrode, and formed by each of the channel formed corresponding to the first electrode and the second electrode. An inductor and a capacitor formed between these inductors exist in a distributed constant manner, and the second electrode is used as a signal input / output path.

(3) The LC element of the present invention is formed on one surface side of a semiconductor substrate, and is formed on the other surface side of the semiconductor substrate, and a non-spiral-shaped first electrode that functions as a gate. a second electrode of the non-spiral shape formed in a position facing the first electrode, the first electrode
And an insulating layer formed between the semiconductor substrate and a source and a drain formed at both ends of a channel formed in the semiconductor substrate corresponding to the first electrode. , A channel formed corresponding to the first electrode, an inductor formed by each of the second electrodes, and a capacitor formed between them are distributed constant, and at least the first electrode is formed. The channel formed corresponding to the electrode of is used as a signal input / output path.

(4) The LC element of the present invention is formed on one surface side of a semiconductor substrate, and is formed on the other surface side of the non-spiral-shaped first electrode that functions as a gate, a second electrode of the non-spiral shape formed in a position facing the first electrode, the first electrode
And an insulating layer formed between the semiconductor substrate and a source or drain formed at one end of a channel formed in the semiconductor substrate corresponding to the first electrode. A channel formed corresponding to the first electrode, an inductor formed by each of the second electrodes, and a capacitor formed between them are distributed constant, and Is used as a signal input / output path.

[0017] (5) LC element of the present invention, the shape of the pre-Symbol first and second electrode may be a serpentine shape.

[0018] (6) LC element of the present invention, the shape of the pre-Symbol first and second electrode may be a wave shape.

[0019] (7) LC element of the present invention is the L C elements, the shape of the first and second electrode includes a curved shape
You may .

[0020] (8) LC element of the present invention, the shape of the pre-Symbol first and second electrode may be a linear shape.

[0021] (9) LC element of the present invention, before Symbol semiconductor substrate surface at a in a position corresponding to the first electrode, may be configured to advance inject carriers.

[0022] (10) LC element of the present invention, relative to prior Symbol first electrode, by longer or shorter length of said second electrode, formed in correspondence to the first electrode may be configured so as to correspond to said channel second electrode partially is.

(11) The LC element of the present invention is the semiconductor
As a substrate, a semiconductor along the first and second electrodes
Use a semiconductor substrate with a layer opposite in polarity to the substrate.
It may be configured as follows.

[0024] (12) LC element of the present invention, as the semiconductor substrate, as a layer to isolate between them between each conductor portions of the first and second electrodes, and the semiconductor substrate
Configured to use a semiconductor substrate with opposite polarity layers
You may.

[0025] (13) LC element of the present invention divides the previous SL second electrode into a plurality, each of the some of the plurality of divided electrode segments may be configured to electrically connect .

[0026] (14) LC element of the present invention divides the previous SL first electrode into a plurality, near each one end of a plurality of channels formed in correspondence to each of the plurality of divided electrode segments the source or drain is provided, these plurality of source or drain so as to be electrically connected to the
You may comprise .

[0027] (15) LC element of the present invention, first and second are pre Symbol electrically connected to the source and drain formed near both ends of the channel formed in correspondence to the first electrode Two input / output electrodes and a ground electrode electrically connected to one end of the second electrode, and a signal is input from one of the first and second input / output electrodes. , Output a signal from the other, and connect or ground the earth electrode to a fixed potential power source
It may be configured as follows .

[0028] (16) LC element of the present invention, prior to SL and the first and second input-output electrode electrically connected near both ends of the second electrode, the first electrode or the first A ground electrode electrically connected to a source or a drain formed in the vicinity of one end of a channel formed corresponding to the electrode piece obtained by dividing the electrode;
A signal may be input from any one of the input / output electrodes and a signal may be output from the other of the input / output electrodes, and the ground electrode may be connected to a fixed-potential power source or grounded.

[0029] (17) LC element of the present invention, first and second are pre Symbol electrically connected to the source and drain formed near both ends of the channel formed in correspondence to the first electrode A channel having two input / output electrodes and third and fourth input / output electrodes electrically connected near both ends of the second electrode, the channel being formed corresponding to the first electrode. and configured for use as a common mode type element both the signal input and output path with the second electrode and
May be .

[0030] (18) LC element of the present invention, by setting the gate voltage to be applied to the front Symbol first electrode variably, the resistance of the channel formed in correspondence to the first electrode And a capacitance value of a capacitor formed in a distributed constant between this channel and the second electrode may be variably controlled.

[0031] (19) The semiconductor device of the present invention, the
The LC element according to any one of (1) to (18) is formed as a part of a substrate, and at least one of a channel formed corresponding to the first electrode and the second electrode is a signal line or a power supply line. configured so as to integrally molded and inserted into the
May be done .

(20) In the LC device of the present invention, an insulating film is formed on the entire surface by a chemical liquid phase method, and a part of the insulating film is removed by etching or laser light irradiation to form a hole, and the hole is formed. The terminals may be attached by sealing with solder to the extent that they rise up on the surface.

[0033] (21) The semiconductor device of the present invention, the
(1), (3), (5) to (13), (15), (1
A buffer for amplifying a signal output through the channel may be connected to either one of the source and the drain of any of the LC elements of 7) .
Yes .

(22) The semiconductor device according to the present invention is as described above.
(1), (3), (5) to (13), (15), (1
A level conversion circuit that changes the voltage level of the signal output through the channel is connected to either the source or the drain of any of the LC elements in 7) .
It may be configured as follows .

[0035] (23) The semiconductor device of the present invention, the
An amplifier is connected in series to the signal input / output path of the LC element according to any one of (1) to (17), and the amplified output is fed back to the signal input / output path to apply the gate voltage applied to the first electrode. by changing, it may be configured to control the frequency variable.

[0036] (24) LC element of the present invention, a protection circuit for bypassing the operating power supply line side or the ground side overvoltage on at least one of the previous SL first and second electrode set <br/> only in so that You may comprise .

(25) In the method of manufacturing an LC element of the present invention, the first step of forming a source and a drain by partially implanting an impurity into a semiconductor substrate, and an insulating layer on the semiconductor substrate are interposed. , to form a first electrode of the non-spiral to produce a channel that serves as an inductor concluded the source and drain, the
A non-spiral-shaped second electrode, which functions as an inductor adjacent to the first electrode and forms a capacitor with the channel, is formed on the semiconductor substrate.
A second step that form, wherein the includes a source, a drain and a third step of forming a wiring layer electrically connected to each of the first and second electrodes.

(26) In the method of manufacturing an LC element of the present invention, a first step of forming a source or a drain by partially implanting an impurity into a semiconductor substrate, and an insulating layer on the semiconductor substrate are interposed. A first electrode having a non-spiral shape, one end of which is located near the source or the drain and which functions as an inductor, is formed on the semiconductor substrate and adjacent to the first electrode. converting mechanism functions as an inductor, and a second step that form the second electrode of the non-spiral to produce a capacitor between said channel, said source or drain and the first and second electrodes And a third step of forming a wiring layer electrically connected to each of them.

[0039]

In the LC element of the invention of (1) , the non-spiral-shaped first and second electrodes are formed substantially parallel to each other on the front surface side of the semiconductor substrate. An insulating layer is formed between at least one of these two electrodes and the semiconductor substrate, and has a MOS structure composed of the first or second electrode, the insulating layer and the semiconductor substrate.

Generally, the inductor functions by forming the conductor into a spiral shape. However, even if the conductor has a shape other than the spiral shape by modifying the shape of the conductor or depending on the frequency band used. Will work as.

As described above, in the LC element of the invention (1), the channel and the second electrode formed corresponding to the non-spiral-shaped first electrode respectively function as inductors. In addition, general MOS ・ FET
Similarly, since a depletion layer is formed on the outer periphery of the channel, a capacitor is distributedly distributed between the channel and the semiconductor substrate around the channel. Moreover, this semiconductor substrate is directly or indirectly connected to the second electrode via the insulating layer, and as a result, a capacitor is formed in a distributed constant manner between the channel and the second electrode. Become.

Therefore, the signal input to the source or the drain formed at one end of the above-mentioned channel, when being propagated through the inductor and the capacitor existing in a distributed constant, has a good attenuation characteristic over a wide band. Is obtained.

In particular, the LC element of the invention (1) is manufactured by forming a source and a drain on a semiconductor substrate, and further forming an insulating layer and non-spiral-shaped first and second electrodes on the surface thereof. It is possible and very easy to manufacture. Further, since this LC element is formed on a semiconductor substrate, it can be formed as a part of an IC or an LSI. Assembly work can be omitted.

Further, in the LC element of the invention of (2) , while the above-mentioned LC element uses the channel as the signal input / output path, the second electrode having a non-spiral shape is used as the signal input / output path. One of the source and the drain is omitted because the signal does not propagate through the channel.

Therefore, the point that the channel and the second electrode each function as an inductor and a capacitor is formed between them in a distributed constant manner is the same as the LC element of the above-mentioned claim 1, and is wide. It has good attenuation properties over the band and is easy to manufacture and can be formed as part of the substrate.

Further, the LC element of the invention of (3) has the non-spiral-shaped first and second electrodes which are arranged in parallel in substantially the same plane in the LC element of the invention of (1) described above. They are arranged so as to face each other with the semiconductor substrate sandwiched therebetween, and the channel formed corresponding to the first electrode and the second electrode each function as an inductor, and a depletion layer is sandwiched between them. The capacitors formed are distributed constant. Therefore, this LC element has an effect that it has good attenuation characteristics over a wide band, is easy to manufacture, and can be formed as a part of a substrate.

Similarly, in the LC element of the invention (4), the two electrodes of non-spiral shape, which are arranged substantially parallel to each other in the substantially same plane in the LC element of the invention (2), are provided.
They are arranged so as to face each other across the semiconductor substrate,
Each of the channel formed corresponding to the first electrode and the second electrode functions as an inductor, and a capacitor exists between them in a distributed constant manner. Therefore, this LC element has an effect that it has good attenuation characteristics over a wide band, is easy to manufacture, and can be formed as a part of a substrate.

Further, in the LC element of the inventions (5) to (8) , the above-mentioned non-spiral shape of the electrode is specifically specified as a meandering shape, a corrugated shape, a curved shape, or a linear shape.

That is, when the electrodes are formed in a meandering shape or a wavy shape, each of the uneven portions becomes a coil of about 1/2 turn and these are connected in series, so that the predetermined inductance as a whole is obtained. Will have. In particular, the meandering shape allows the adjacent electrodes to come close to each other, so that the space can be effectively used. Further, when the frequency band used is limited to the high frequency region, the electrode has a predetermined inductance even when the electrode is formed into a curved shape or a linear shape, and the same operation as when the electrode is formed in a meandering shape or the like. Can be done.

Further, in the LC element of (9) , by injecting carriers in advance to the position corresponding to the first electrode,
It is formed as a depletion type element. In this case, a channel is formed without applying a voltage (gate voltage) to the first electrode or the relationship between the applied gate voltage and the channel width is changed without changing the characteristics of the LC element itself. be able to.

Further, in the LC element of (10) , one of the first and second electrodes is formed short, and even in this case, the first and second electrodes having different lengths are similarly formed. Each of the electrodes functions as an inductor, and a capacitor formed with a depletion layer sandwiched between these electrodes exists in a distributed constant manner. Therefore, this LC element has an effect that it has good attenuation characteristics over a wide band, is easy to manufacture, and can be formed as a part of a substrate.

[0052] Further, (11) In the LC elements, focusing on the opposite conductivity type layer between the non-spiral shaped contacting adjacent npn
Since the structure or the pnp structure is obtained, good isolation can be performed. Therefore, it is possible to easily form a state in which the capacitor is formed in a distributed constant manner only between the channel formed corresponding to the first electrode and the second electrode arranged adjacent to this channel. The LC element can have good attenuation characteristics over a wide band.

[0053] Further, connected via an npn structure or pnp structure in LC devices, channels are arranged ho <br/> pot facing the other than the second electrode, which is between the invention of (12) Therefore, good isolation can be performed. Therefore, it is possible to easily form a state in which a capacitor is formed in a distributed constant manner only between a pair of channels and a second electrode arranged opposite to each other, and this LC element has a good attenuation characteristic over a wide band. Can have.

Further, in the LC element of the invention of (13) , the second electrode is divided into a plurality of electrode pieces and a part of these is electrically connected for use. In this case, the self-inductance of each segment becomes small, and it is possible to form a distributed constant type LC element that is less affected by the self-inductance of each segment.

Further, in the LC element of the invention of (14) , the first electrode is divided into a plurality of electrode pieces, and the channel corresponding thereto is also divided and formed. Therefore, similarly to the LC element of the thirteenth aspect, the self-inductance of each divided channel becomes small, and it is possible to form a distributed constant type LC element that is less affected by this.

Further, in the LC element of the invention of (15), the first and second input / output electrodes connected to the source and drain near both ends of the channel formed corresponding to the first electrode are provided. By providing the ground electrode near one end of the second electrode, it is possible to easily form a three-terminal type LC element in which the channel is used as a signal input / output path.

Further, in the LC element of the invention of (16) , the first and second input / output electrodes are provided near both ends of the second electrode and connected to the source or drain formed at one end of the channel. By providing the ground electrode, it is possible to easily form a three-terminal type LC element in which the second electrode is used as a signal input / output path.

Further, in the LC element of the invention of (17) , the first and second input / output electrodes are provided on the source and drain formed at both ends of the above-mentioned channel, and the first and second input / output electrodes are provided near both ends of the second electrode. By providing the third and fourth input / output electrodes, a 4-terminal common mode type LC element can be easily formed.

Further, in the LC element of the invention of (18), the gate voltage applied to the first electrode is variably set so that the non-spiral shaped channel formed corresponding to the first electrode is formed. The width, that is, the resistance value of the channel changes. Further, since the depletion layer formed on the outer periphery of the channel also changes, the capacitance of the capacitor formed between the channel and the second electrode also changes. Therefore, it is possible to change the resistance value of the channel and the capacitance of the capacitor formed in a distributed constant manner between the channel and the second electrode by changing the gate voltage, and the attenuation characteristic is required. It can be variably controlled accordingly.

Further, in the semiconductor device of the invention (19) ,
The LC element of each of the above claims is formed on a part of the substrate so as to be inserted into the signal line or the power supply line.
As a result, it can be manufactured integrally with other components on the semiconductor substrate, which facilitates the manufacturing and eliminates the work of assembling the components in the subsequent process.

The LC element of the invention of (20) is the LC element of any one of the inventions of (1) to (14) described above.
After being formed on the semiconductor substrate, an insulating film is formed on the entire surface by the chemical liquid phase method. After that, a hole is formed in a part of the insulating film by etching or laser light irradiation, and solder is put in the hole to attach a terminal. Therefore, it is possible to easily manufacture the surface mount type LC element, and the surface mount type LC element also facilitates the assembling work of the LC element.

Further, in the semiconductor device of the invention (21) ,
A buffer that amplifies a signal output through the channel of the above-described LC element is connected, and a signal whose voltage level is attenuated by passing through a channel having a larger resistance value than a metal material such as aluminum is used. Can be restored to a good original signal.

In the semiconductor device of (22) ,
A level conversion circuit is connected instead of the buffer described above. By connecting this level conversion circuit, it is possible to restore the signal level attenuated via the channel and perform conversion or level correction of a predetermined level.

Further, in the semiconductor device of the invention (23) ,
An amplifier is connected in series to the signal input / output path of the LC element described above, and the amplified output is fed back to the input side. Oscillation is performed by forming such a feedback loop, and the LC element described above changes the resistance of the channel and the channel between the second electrode and the channel by changing the gate voltage applied to the first electrode. It is possible to change the capacitance of the capacitor formed in a distributed constant, so that the voltage controlled oscillator whose output frequency can be controlled according to the gate voltage can be easily configured.

Further, in the LC element of the invention of (24) , the protection circuit is connected to at least one of the first and second electrodes, and when an overvoltage is applied to these electrodes, the operating power supply line A bypass current flows to the side or the ground side, and dielectric breakdown between the first and second electrodes and the semiconductor substrate can be prevented.

Further, L of the inventions of (25) and (26)
The C element manufacturing method is a method for manufacturing each of the LC elements described above by applying a semiconductor manufacturing technique. That is,
In the first step, both or one of the source and drain is formed on the semiconductor substrate, and then, in the second step, the insulating layer and the first and second electrodes are formed on the surface of the semiconductor substrate. Then, in the third step, a wiring layer including input / output electrodes and the like is formed to complete the LC element described above.

As described above, the above-mentioned LC element can be manufactured by applying a general semiconductor manufacturing technique (particularly MOS manufacturing technique), and can be miniaturized or reduced in cost, and a plurality of LC devices can be manufactured. It is also possible to mass-produce at the same time.

[0068]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An LC device of an embodiment to which the present invention is applied will be specifically described below with reference to the drawings.

First Embodiment FIG. 1 is a plan view of an LC device of the first embodiment to which the present invention is applied. 2 is an enlarged sectional view taken along the line AA of FIG. 1, FIG. 3 is an enlarged sectional view taken along the line BB of FIG. 1, and FIG. 4 is an enlarged sectional view taken along the line CC of FIG.

As shown in these figures, the LC of this embodiment is
The device 100 is a p-type silicon substrate (p
(Si substrate) 30 is formed by connecting a source 12 and a drain 14 formed at a separated position near the surface of the substrate by a channel 22 formed by applying a voltage to the meandering first electrode 10. ing.

Source 12 and drain 14 described above
Is formed as an n + region obtained by inverting the p-Si substrate 30. For example, it is formed by implanting As @ + ions by thermal diffusion or ion implantation to increase the impurity concentration.

The first electrode 10 functions as a gate, and one end of the meandering shape overlaps part of the source 12 and the other end overlaps part of the drain 14, The insulating layer 28 formed on the front surface side of the p-Si substrate 30 is sandwiched. The first electrode 10 is formed, for example, by forming an aluminum film or by heavily doping P by diffusion or ion implantation.

The insulating layer 28 is formed on the surface of the p-Si substrate 30 and the p-Si substrate 30 and the first electrode 10.
It is to insulate and. As shown in FIG. 2A, the entire surface of the p-Si substrate 30 except for a second electrode 26 described later is covered with this insulating layer 28, and the surface of this insulating layer 28 is covered with the above-mentioned first layer. The electrode 10 is formed. The insulating layer 28 is made of, for example, P-added SiO 2.
2 (P-glass).

A second electrode 26 is formed substantially parallel to the above-mentioned first electrode 10. This second electrode 2
A channel 22 is formed on the surface of the p-Si substrate 30 facing the first electrode 10 by applying a predetermined gate voltage between the electrode 6 and the first electrode 10.

Further, the above-mentioned first electrode 10 and source 1
2, the drain 14 and the second electrode 26 respectively include a ground electrode 16 and an input / output electrode 1 as shown in FIGS.
8, 20 and the control electrode 24 are connected. That is, the control electrode 24 is attached to the first electrode 10 outside the active region so as not to damage the thin gate film, as shown in FIG. Further, as shown in FIGS. 3 and 4, the mounting of the input / output electrode 18 to the source 12 and the mounting of the input / output electrode 20 to the drain 14 are performed after exposing a part of the source 12 and the drain 14. It is performed by attaching a metal film such as aluminum. Furthermore, the ground electrode 1 for the second electrode 26
The attachment of 6 is performed at a position separated from the active region so as not to damage the thin gate film like the control electrode 24.

Assuming that the LC element 100 of the present embodiment having the above-mentioned structure has an n-channel enhancement type structure, the channel is not formed until the positive voltage is applied to the first electrode 10. 22 will be formed.

FIGS. 2A and 2B are views showing a state in which a channel is formed. The control electrode 2 connected to the first electrode 10, that is, the first electrode 10
In the state in which the positive gate voltage is not applied to No. 4, the channel 22 does not appear on the surface of the p-Si substrate 30 as shown in FIG. Therefore, in this state, the source 12 and the drain 14 shown in FIG. 1 are insulated.

However, when a positive gate voltage is applied to the first electrode 10, as shown in FIG.
N near the surface of the p-Si substrate 30 corresponding to the electrode 10 of
A channel 22 consisting of a region appears. In addition, p-Si
Inside the substrate 30 and outside this channel 22,
A positive gate voltage applied to the first electrode 10 forms a depletion layer 32 in which holes are excluded. Therefore,
Electrons in the channel 22 and pS are sandwiched by the depletion layer 32.
The holes in the i-substrate 30 are arranged to face each other to form a capacitor. Moreover, this capacitor is the first electrode 1
Since it is formed over substantially the entire length of 0, a capacitor is formed in a distributed constant manner between the second electrode 26 connected to the p-Si substrate 30 and the channel 22.

The positive gate voltage applied to the first electrode 10 means the p-Si substrate 3 corresponding to the substrate.
The voltage of 0, that is, a positive voltage with respect to the voltage applied to the second electrode 26 formed on the surface of the p-Si substrate 30, means that the channel 22 is provided between the source 12 and the drain 14. Source 1 to be connected
2 and the voltage of the drain 14 also need to be relatively positive.

FIG. 5 shows a cross-sectional structure of the LC element 100 of this embodiment, and shows a cross section of the first electrode 10 taken in the meandering direction. As shown in the figure, a channel 22 is formed in parallel with the first electrode 10, and the channel 22 makes the source 10 and the drain 14 conductive. For example, in the case of the enhancement type, the channel 22 is formed and the source 12 and the drain 14 are brought into conduction only when the gate voltage is applied to the first electrode 10, but the channel is applied to the first electrode 10. Since the width and depth of the channel 22 are changed by changing the gate voltage, the resistance value between the source 12 and the drain 14 can be changed.

Further, as shown in FIG. 2B, the surface area of the channel 22 is changed by changing the width and depth of the channel 22, and the surface area of the depletion layer 32 is changed accordingly. That is, as the surface area changes, the channel 22
The capacitance of the capacitor formed in a distributed constant between the second electrode 26 and the second electrode 26 also changes, and as a result, the capacitance can be changed by changing the gate voltage.

FIG. 6 is a diagram showing the principle of an inductor formed by meandering electrodes. As shown in the figure, when a current in one direction is applied to the channel 22 or the second electrode 26 having a meandering shape that is bent in a concavo-convex shape, a magnetic flux whose direction is opposite in the adjacent concavo-convex portion is generated. They are generated alternately, and it is as if 1/2 turn coils were connected in series. Actually, comparing the meandering electrode and the spiral electrode, the length of the electrode that can be formed in the same area when the width of the electrode and the interval between the adjacent electrodes are the same is the meandering electrode. It has been confirmed that is longer than the spiral electrode and there is not much difference in the value of inductance.

When a spiral electrode is used,
One of the two ends of the electrode is located in the central part and the other is located in the peripheral part, whereas the meandering electrode has both ends of the electrode located in the peripheral part. It is convenient when connecting with.

In the LC element 100 of this embodiment having such a structure, the channel 22 and the second electrode formed corresponding to the meandering first electrode 10 respectively function as inductor conductors. . Also, channel 2
Channel 2 with a depletion layer 32 formed on the outer periphery of
A capacitor is formed between the second electrode 26 and the second electrode 26.
Therefore, the LC element 100 has the inductor formed by the channel 22 and the second electrode 26 and the capacitor formed by sandwiching the depletion layer 32 in a distributed constant manner.

FIG. 7 is a diagram showing an equivalent circuit of the LC device 100 of the first embodiment. The equivalent circuit shown in FIG.
It is shown that the channel 22 is formed by applying a predetermined gate voltage to the control electrode 24, the channel 22 is used as a signal input / output path, and the ground electrode 16 is grounded. It functions as an element.

In this case, the channel 22 functions as an inductor conductor having the inductance L1, and the second electrode 26 functions as an inductor conductor having the inductance L2. Further, a capacitor having a predetermined capacitance C is formed in a distributed constant manner between these two inductor conductors. Therefore, this LC
The element 100 can exhibit an excellent attenuation characteristic that the conventional lumped-constant type element does not have, and only a predetermined frequency component is removed from the signal input from one of the input / output electrodes 18 and 20 and the other. Will be output from.

Although the ground electrode 16 is grounded in FIG. 9A, the ground electrode 16 may be connected to a power source having a predetermined potential.

Further, FIG. 7B shows an equivalent circuit in the case of applying a variable control voltage Vc to the control electrode 24. The control voltage Vc applied to the control electrode 24 is the gate voltage itself. By changing the voltage Vc, the depth of the channel 22 is changed, so that the mobility of the channel 22 itself is changed, and as a result, the source 12 and the drain 14 are changed. The resistance value between and can be changed arbitrarily. At the same time, channel 2
As described above, the capacitance C between the second electrode 26 and the second electrode 26 can be changed.

Therefore, when the resistance value of the channel 22 and the capacitance C existing between the channel 22 and the second electrode 26 in a distributed constant are changed, the attenuation characteristic of the LC element 100 is changed as a whole. Become. In other words, by changing the control voltage Vc, the characteristics of the LC element 100 of this embodiment can be arbitrarily changed within a certain range.

FIG. 7C is a functional block diagram of the equivalent circuit shown in FIG. 7B. The variable resistor connected in series to the channel 22 by changing the control voltage Vc. Resistance of the channel 22 and the second
It is shown that the capacitance of the variable capacitance formed in a distributed constant manner between the electrode 26 and the electrode 26 can be changed.

In the above-mentioned LC element 100, the case where the n channel is formed between the source 12 and the drain 14 has been described. In this case, since electrons are used as carriers, the mobility is large and the channel 22 Resistance is reduced. On the other hand, the LC element 100 described above may be formed by forming a p-channel on the n-Si substrate. In this case, since holes are used as carriers, the resistance of the channel 22 becomes relatively large, and it has different characteristics as compared with the case of the n channel described above.

FIG. 8 shows that the gate voltage (control voltage Vc) applied to the first electrode 10 is changed to change the channel 2
2 is a diagram for explaining the channel resistance R when the depth of 2 is changed. FIG. In the figure (A), the first meandering shape is actually used.
FIG. 6 is a plan view when the electrode 10 of FIG.
FIG. 3B is a sectional view taken along the line AA.

In the figure, W is the gate width and X is the channel depth. The first electrode 1 having such a width W
When the channel 22 is formed by 0, the formed channel width becomes (W + 2X). Therefore, the resistance R between the source 12 and the drain 14 of the channel 22 is
Can be calculated by R = ρ / (W + 2X). Here, ρ is the resistance per unit area of the channel 22, and in the above equation, the channel resistance R is proportional to the channel length L, and the channel width (W + 2
X) is inversely proportional to.

Next, the manufacturing process of the LC device 100 of this embodiment will be described.

FIG. 9 is a diagram showing the manufacturing process of the LC element 100 of this embodiment, and shows the enhancement type LC element 100 as an example. The drawing shows a cross section in the meandering direction of the first electrode 10.

(1) Formation of Oxide Film: First, the surface of the p-Si substrate 30 is thermally oxidized to form SiO2 (FIG. 9 (A)).

(2) Source / drain window opening: Next, the oxide film on the surface of the p-Si substrate 30 is photo-etched to open windows corresponding to the source 12 and the drain 14 ( The same figure (B)).

(3) Formation of Source / Drain: Next, the source 12 and the drain 14 are formed by implanting an n-type impurity from the windowed portion (FIG. 7C). For example, As + is used as the n-type impurity, and this impurity is implanted by thermal diffusion. When implanting by ion implantation, the window opening in (2) described above is unnecessary.

(4) Removal of gate region: Next, the opening of the gate region is formed by removing the oxide film in the portion where the first electrode 10 is to be formed (FIG. 3D). In the case of the LC element 100 of the present embodiment, since the first electrode 10 needs to be formed in a meandering shape, the gate region opening is also formed in a meandering shape. In this way, p of the portion corresponding to the first electrode 10
-Si substrate 30 will be exposed.

(5) Formation of Gate Oxide Film: Next, p-Si substrate 3 partially exposed in this way
A new oxide film, that is, an insulating layer 28 is formed for 0 (FIG. 7E).

(6) Formation of Gate and Other Electrodes: Next, the first electrode 10 functioning as a gate is formed by vapor-depositing aluminum, for example, and the control connected to the first electrode is performed. Electrodes 24 and input / output electrodes 18, 2 connected to the source 12 and the drain 14
0 and 0 are formed, respectively (FIG. (F)).

The second electrode 2 is formed before or after the steps (4) to (6) or in parallel with the steps (4) to (6).
The second electrode 2 is opened by opening a window corresponding to
6 and the ground electrode 16 connected thereto are formed.

(7) Formation of Insulating Layer: Finally, P-glass is adhered to the entire surface and then heated to form a smooth surface (FIG. (G)).

The process of manufacturing the LC element 100 in this manner is basically similar to the process of manufacturing a normal MOS • FET, and the shape of the first electrode 10 is different. Therefore, the manufacturing itself can be dealt with by changing the shape of the photomask or by partially changing the order of steps for manufacturing a general MOS • FET.
Therefore, it can be formed on the same substrate as a general MOS FET or bipolar transistor. Therefore, it can be formed as a part of an IC or LSI, and when it is formed as a part of these parts, the work of assembling the parts in the subsequent process can be omitted.

As described above, the LC device 100 of this embodiment is used.
Is a channel 22 formed corresponding to the first electrode 10.
And the second electrode 26 form an inductor, and a capacitor is formed between the channel 22 and the second electrode 26 in a distributed constant manner.

Therefore, when the ground electrode 16 provided at one end of the second electrode 26 is connected to the ground or a fixed potential and the channel 22 is used as a signal input / output path, the input signal On the other hand, the LC element has a good attenuation characteristic in a wide band.

In addition, as described above, this LC device 100
Can be manufactured by applying general MOS / FET manufacturing techniques, and is therefore easy to manufacture and suitable for miniaturization. In addition, when the LC element is manufactured as a part of the semiconductor substrate, wiring with other components can be performed at the same time, which eliminates the need for assembling work in the subsequent process.

In addition, the LC element 100 of this embodiment is the first
Gate voltage (control voltage V
By changing c), it is possible to variably control the resistance value of the channel 22 and the capacitance of the capacitor formed in a distributed constant manner between the channel 22 and the second electrode 26. The entire frequency characteristic can be adjusted or changed.

In the first embodiment described above, the channel 22 formed corresponding to the first electrode 10 was used as the signal input / output path, but the channel 22 and the second electrode 26 may be replaced with each other. You may That is, as shown in FIG. 10, the input / output electrodes 18, 20 are provided on both ends of the second electrode 26.
This second electrode 26 is used as a signal input / output path by connecting to each other, and the source 12 (or the drain 14 may be formed) formed at one end of the channel 22.
The ground electrode 16 is connected to, and the ground electrode 16 is grounded or connected to a fixed potential. However, in this case, since the ground electrode 16 is connected to either one of the source 12 and the drain 14, the other can be omitted.

Further, in FIG. 11, the second electrode 26 is replaced with p-Si.
FIG. 9 is a diagram showing a modification example in which the first electrode 10 is arranged so as to substantially face the first electrode 10 on the opposite surface (back surface) side of the substrate 30.
12 is a view showing an enlarged cross section taken along the line AA of FIG. 11 and corresponds to FIG. FIG. 13 shows the LC element shown in FIG. 11 in which the second electrode 26 is used as a signal input / output path, and corresponds to FIG. 10 described above.

As described above, the meandering first and second electrodes 10 and 26 are arranged substantially opposite to each other with the p-Si substrate 30 interposed therebetween, that is, the channel 22 and the second electrode 26 are arranged substantially opposite to each other. Even if the LC shown in FIG.
Like the device 100, the channel 22 and the second electrode 2
Each of 6 functions as an inductor, and a capacitor is formed between them in a distributed constant manner, which has good frequency characteristics and is easy to manufacture. In particular, when the first and second electrodes 10 and 26 are made to face each other in this manner, the mounting area can be made smaller than in the case where they are arranged in parallel in substantially the same plane as shown in FIG. There is also.

Second Embodiment Next, an LC device according to a second embodiment of the present invention will be specifically described with reference to the drawings.

The LC element 100 of the first embodiment described above is
The channel 22 formed corresponding to the first electrode 10 and the second electrode 26 are formed in parallel over substantially the entire length, that is, in substantially the same length. However, the LC element 200 of the present embodiment. Is characterized in that the second electrode 26 shown in FIG. 1 is approximately half the length.

FIG. 14 shows an LC device 200 of the second embodiment.
FIG. As shown in the figure, even when a part of the second electrode 26 is omitted, a channel formed corresponding to the shortened second electrode 26 and the longer first electrode 10 22 and the capacitor formed by the channel 22 and the second electrode 26 are formed in a distributed constant manner, so that the LC element 100 of the first embodiment shown in FIG. It will also have good damping characteristics.

FIG. 15 is a diagram showing an equivalent circuit of the LC element 200 of this embodiment. As shown in the figure, the inductance L3 also decreases as the number of meandering of the second electrode 26 decreases, and correspondingly the capacitance C1 existing in a distributed constant also decreases.

Further, by changing the gate voltage applied to the control electrode 24, the resistance value of the channel 22 formed corresponding to the first electrode 10 and the second electrode in which the number of meandering with the channel 22 is reduced. The capacitance formed between the LC device 1 and the device 26 also changes, and the attenuation characteristic of the LC device 200 can be variably controlled.
The same as 00.

As described above, the LC device 200 of this embodiment is used.
Is a channel 22 formed corresponding to the first electrode 10.
The second electrode 26 shorter than the first electrode 10 forms the inductor and the capacitor in a distributed constant manner, and can function as an element having a good attenuation characteristic.

Further, the LC element 200 can be manufactured by utilizing a semiconductor manufacturing technique, can be formed as a part of an LSI, etc., and in this case, a wiring process in a subsequent process can be omitted, and it can be used for control. The LC element 100 of the first embodiment described above is capable of changing the attenuation voltage as an element by variably controlling the inductance of the inductor and the capacitance value of the capacitor by changing the gate voltage applied to the electrode 24. Is the same.

The LC element 200 of this embodiment is the first
Although the channel 22 formed corresponding to the electrode 10 of FIG. 2 was used as a signal input / output path, the channel formed corresponding to the first electrode 10 using the second electrode 26 as a signal input / output path. The 22 side may be connected to ground or a fixed potential.

FIG. 16 is a diagram showing a modification in which the second electrode 26 is used as a signal input / output path, and corresponds to FIG. 10 of the first embodiment. In this case, the second
The input / output electrodes 18 and 20 are connected to both ends of the electrode 26, and the ground electrode 16 is connected to the source 22 (or drain 14) provided at one end of the channel 22 formed corresponding to the first electrode 10. Connecting. Further, by forming the first electrode 10 to be about half the length of the second electrode 26, the channel 22 formed corresponding to the first electrode 10 is also about half the length. .

Even in such a case, the first electrode 1
Channel 22 and second electrode 26 formed corresponding to 0
And function as inductors, respectively, and capacitors are formed between them in a distributed constant manner, so that good attenuation characteristics can be obtained as in the LC element 200 shown in FIG.

In FIG. 17, the short second electrode 26 is replaced with p-Si.
FIG. 15 is a diagram showing a modified example in which the first electrode 10 (that is, the channel 22) is arranged on the opposite surface side of the substrate 30 so as to substantially face the first electrode 10 and corresponds to FIG. 14. In addition, FIG.
Arranges the second electrode 26 on the opposite surface side of the p-Si substrate 30 so as to substantially face the first electrode 10, and
First electrode 10 and correspondingly formed channel 22
It is a figure which shows the modification which shortened, and corresponds to FIG.

As shown in these figures, even when the channel 22 having a meandering shape and different length and the second electrode 26 are arranged so as to face each other, the same as in the LC element 200 shown in FIG. 14 and the like. In addition, each of the channel 22 and the second electrode 26 functions as an inductor and a capacitor is formed between them in a distributed constant manner, which has good frequency characteristics and is easy to manufacture. Will have advantages.

Third Embodiment Next, regarding the LC device 300 of the third embodiment of the present invention,
A specific description will be given with reference to the drawings.

The LC element 100 of the first embodiment and the LC element 200 of the second embodiment described above function as a normal mode type element with three terminals.
The C element 300 is characterized in that it is formed so as to function as a 4-terminal common mode element.

FIG. 19 is a plan view of the LC device of the third embodiment. As shown in the figure, the LC device 30 of the third embodiment
0 is provided with input / output electrodes 36 and 38 at both ends of the second electrode 26, and this point shows that the LC element 100 shown in FIG.
Is different from

FIG. 20 is a diagram showing an equivalent circuit of the LC element of the third embodiment. As shown in the figure, the channel 22 formed between the two input / output electrodes 18 and 20 via the source 12 and the drain 14 functions as an inductor having the inductance L1 and the two input / output electrodes 36 and 38. The second electrode 26 formed therebetween functions as an inductor having the inductance L2. Moreover, the channel 22 and the second electrode 26 are used as signal input / output paths, respectively, and a capacitor having the capacitance C is distributed between these channels and the second electrode 26, like the LC element 100 of the first embodiment. It is formed constantly.

As described above, the LC device 300 of this embodiment is used.
Is a channel 22 formed corresponding to the first electrode 10.
By providing two input / output electrodes 36 and 38 on both ends of the second electrode 26 as well, it is possible to function as a four-terminal common mode element having good attenuation characteristics. Further, by changing the gate voltage applied to the control electrode 24, the resistance value and the distributed constant capacitance C included in the inductor having the above-described inductance L1 can be changed, and the attenuation characteristic of the LC element 300 as a whole can be changed. Can be controlled.

FIG. 21 is a view showing a modified example in which the second electrode 26 is arranged on the opposite surface side of the p-Si substrate 30 so as to substantially face the first electrode 10 (that is, the channel 22). is there. As shown in the figure, the meandering channel 2
Even when the second electrode 26 and the second electrode 26 are arranged so as to face each other, like the LC element 300 shown in FIG.
A four-terminal common mode element in which a capacitor is formed in a distributed constant manner between these elements can be obtained, which has advantages such as good frequency characteristics and easy manufacture.

Fourth Embodiment Next, an LC device according to a fourth embodiment of the present invention will be specifically described with reference to the drawings.

The LC elements 100 and 20 of the above-mentioned respective embodiments
In each of 0 and 300, the second electrode 26 was formed by one conductor, but the LC element 400 of the present embodiment has a plurality of (for example, two) divided electrode pieces for the second electrode 26. 26
It is characterized in that it is divided into -1, 26-2.

FIG. 22 is a plan view of the LC device of the fourth embodiment. As shown in the figure, the LC device 40 of the fourth embodiment
0 has a structure in which the second electrode 26 used in the LC element 100 shown in FIG. 1 is replaced with two divided electrode pieces 26-1 and 26-2. The ground electrode 16 is connected to each of the split electrode pieces 26-1 and 26-2 having a meandering shape as a whole. By grounding the two ground electrodes 16, two split electrode pieces 26-
A part of the inductor formed by each of 1 and 26-2 is grounded. Alternatively, by connecting the two ground electrodes 16 to a power source having a fixed potential, a part of the inductor formed by each of the two divided electrode pieces 26-1 and 26-2 has the fixed potential.

FIG. 23 is a diagram showing an equivalent circuit of the LC element 400 of the fourth embodiment. As shown in the figure, the entire channel 22 formed corresponding to the first electrode 10 functions as an inductor having an inductance L1, and each of the divided electrode pieces 26-1 and 26-2 has an inductance L3. , L4. Then, the channel 22 and each divided electrode piece 26-1,
26-2 functions as a capacitor having capacitors C2 and C3, and these capacitors are formed in a distributed constant.

In the LC element 400 of this embodiment, the self-inductances L3 and L4 of the divided electrode pieces 26-1 and 26-2 are used.
Becomes smaller. Therefore, the influence of these self-inductances on the characteristics of the LC element 400 as a whole is reduced, and the channel 22 formed corresponding to the first electrode 10 is formed.
The characteristics of the LC element 400 as a whole are substantially determined by the inductance L1 and the capacitance constants C2, C3 formed in a distributed constant.

Further, the characteristics of the LC element 400 as a whole can be variably controlled by changing the gate voltage applied to the control electrode 24, as in the above-described embodiments.

In the LC element 400 of the present embodiment, the planar structure of which is shown in FIG. 22, the channel 22 formed corresponding to the first electrode 10 is used as a signal input / output path and the second electrode 26 is used. Was divided into two, but on the contrary, the second
The electrode 26 of the
The electrode 10 side may be divided into a plurality of parts. In this case, since the channel 22 is formed corresponding to each of the plurality of divided first electrodes 10, the source 12 or the drain 14 is provided near one end of each channel, and the ground electrode 16 is provided thereto. Just connect.

FIG. 24 shows two divided electrode pieces 26-1 and 26-2.
6-2 on the opposite surface side of the p-Si substrate 30 to the first electrode 1
It is a figure which shows the modification at the time of arrange | positioning so that it may oppose 0 substantially. As shown in the figure, even when the meandering channel 22 and the two divided electrode pieces 26-1 and 26-2 are arranged so as to face each other, the LC element 4 shown in FIG.
00, each channel 22 and each divided electrode piece 26-
Each of 1 and 26-2 functions as an inductor, and a capacitor is formed between them in a distributed constant manner, which has good frequency characteristics and has advantages such as easy manufacturing. Become.

Fifth Embodiment Next, an LC element according to a fifth embodiment of the present invention will be specifically described with reference to the drawings.

In general, the conductor has a spiral shape and functions as an inductor conductor having a predetermined inductance. In addition, as described above, even when the channel 22 and the second electrode 26 have a meandering shape, they function as an inductor conductor having a predetermined inductance. However, when the frequency band of the input signal is limited to high frequencies, it functions as an inductor conductor having an inductance component even if it has a shape other than a spiral shape or a meandering shape, or in the extreme case a linear shape. LC of this example
Focusing on such a point, the element is characterized in that the channel 22 and the second electrode 26 formed corresponding to the first electrode 10 are formed in a shape other than the meandering shape.

FIG. 25 and FIG. 26 are plan views of the LC element of this embodiment in which the channel 22 formed corresponding to the first electrode 10 and the second electrode 26 are each linear.

FIG. 25A corresponds to FIG. 1 described above, and shows a three-terminal type LC element in which the channel 22 and the second electrode 26 have substantially the same length and are formed substantially parallel to each other. ing. 14B corresponds to FIG. 14, and shows an LC element in which the second electrode 26 is provided corresponding to a part of the channel 22 formed corresponding to the first electrode 10. There is.

FIG. 26A corresponds to FIG. 19 and shows the case where input electrodes 36 and 38 are provided at both ends of the second electrode 26 to form a four-terminal common mode type element. . 22B corresponds to FIG. 22, and shows an LC element in which the second electrode 26 side is divided into two divided electrode pieces 26-1 and 26-2.

25 and 26 described above show an LC element in which the first electrode 10 and the second electrode 26 are formed in substantially the same plane, but as shown in FIG. 11 and the like. The first electrode 10 and the second electrode 26 are connected to the p-Si substrate 30.
The same applies to the case where they are arranged so as to be substantially opposite to each other with sandwiching therebetween.

FIG. 27 is a plan view of an LC element in which the first electrode 10 and the channel 22 and the second electrode 26 formed corresponding thereto have a curved shape, and the curved shape has a large radius of curvature. The case of is shown. When another component or the like has to be arranged at a position where the two input / output electrodes 18 and 20 are connected by a straight line, the first and second electrodes 10 and 26 may have a curved shape as shown in FIG. Good.

FIG. 28 is a plan view of an LC element in which the first electrode 10 and the channel 22 and the second electrode 26 formed corresponding to the first electrode 10 have a corrugated shape. This LC element has a larger inductance than that of the case where the channel 22 and the second electrode 26 have a linear shape or a curved shape with a large radius of curvature, though not so much as the meandering shape shown in FIG.

FIG. 29 is a plan view of an LC element in the case where the first electrode 10, the channel 22 and the second electrode 26 formed corresponding to the first electrode 10 have a circular shape less than one round. As shown in the figure, by forming the channel 22 and the second electrode 26 in a substantially circular shape, an LC element having a small inductance can be formed.
In addition, by partially folding back one or both ends of the first electrode 10 (channel 22) and the second electrode 26, the magnetic flux generated by the channel 22 and the like is partially canceled to reduce the inductance, and the entire LC element is reduced. , The frequency characteristic can be adjusted.

Note that, in each of FIGS. 27 to 29 described above, only the LC element corresponding to FIG. 25A is shown for simplification of description, but FIGS.
The type corresponding to each of the above and the type in which the first electrode 10 and the second electrode 26 are arranged so as to face each other with the p-Si substrate 30 interposed therebetween can be considered in the same manner.

As described above, the LC shown in FIGS.
The element has the first electrode 10 and the channel 22 and the second electrode 26 formed corresponding thereto having a shape other than the meandering shape, and is similar to the above-described first to fourth embodiments. In addition, it can function as an element having good attenuation characteristics. Further, by changing the gate voltage applied to the first electrode 10 via the control electrode 24, the resistance value of the channel 22 is changed and the capacitance of the capacitor formed in a distributed constant is also changed, so that the characteristics of the entire LC element are changed. The point that it can be variably controlled is also the same as in each of the above-described embodiments.

Other Examples Next, LC elements according to other examples of the present invention will be specifically described with reference to the drawings.

FIG. 30 and FIG. 31 are diagrams showing the outline of the case where terminals are attached using the chemical liquid phase method. Figure 30
2 is a plan view of the LC element 500 of this embodiment corresponding to FIG. 1 and the like. As shown in the figure, the first electrode 10 and the second electrode 26 of the LC element 500 are provided at both ends or one end for control. The electrode 24 and the ground electrode 16 are not provided.

A single LC element 50 is a semiconductor substrate including the first and second electrodes 10 and 26 having such a shape.
After separating by 0, as shown in the cross section taken along the line EE of FIG. 30 in FIG. 31, a silicon oxide film 40 is formed as an insulating film on the entire surface of the individually separated chips (elements) by the chemical liquid phase method. To do. After that, the silicon oxide film 40 on one end of the first and second electrodes 10 and 26 is etched.
Is removed to form a hole, and the hole is sealed with solder 42 to the extent that it rises on the surface, so that the protruding solder 42 can be brought into direct contact with the land or the like of the printed wiring board. Therefore, it is convenient for surface mounting.

Incidentally, another insulating material such as synthetic resin may be used for the protective film on the element surface, and a laser beam may be used for perforating the protective film. Further, as shown in FIG. 31, by adjusting the film thickness of each electrode so that the heights of the input / output electrode 18, the first electrode 10, the second electrode 26, etc. are the same, the height of the protruding solder 42 is increased. Since they are almost the same, it is more convenient for surface mounting. Further, as shown in FIG. 11, when the second electrode 26 is arranged so as to substantially face the first electrode 10, the solder 42 is projected only on one surface side by utilizing the through hole, Wiring processing and the like in the subsequent process becomes easy.

FIG. 32 shows the LC element 1 of each of the above-mentioned embodiments.
It is explanatory drawing at the time of forming 00 etc. as a part of LSI etc. As shown in the figure, each of the LC elements 1 described above is connected to a line 48 for various signals or power on the semiconductor chip 46.
Incorporate by inserting 00 etc. In particular, the LC element 100 and the like of each of the above-described embodiments can be manufactured at the same time in the process of forming various circuits on the semiconductor chip 46, so that there is an advantage that the wiring process and the like in the subsequent process are unnecessary.

Next, an example of using the above-mentioned LC element as a part of an actual circuit will be described.

In general, the LC device 10 of each of the above-mentioned embodiments
At 0 or the like, the channel 22 forming the inductor has a high resistance, and since the channel 22 has a long total length, the signal level is attenuated between the two input / output electrodes 18 and 20. Therefore, when the LC element 100 or the like is actually used as a part of the circuit, a practical configuration is achieved by connecting a buffer having a high input impedance to the output side.

FIG. 33 is a diagram showing an example in which a buffer is connected to the output side. FIG. 1A shows a MOS as a buffer.
-The case where the source follower circuit 50 which consists of FET and resistance is used is shown. The MOS • FET which constitutes the source follower circuit 50 is the LC element 10 of each of the above-mentioned embodiments.
Since it has the same MOS structure as 0 or the like, the whole including the source follower circuit 50 can be integrally formed as an LC element.

Further, FIG. 19B shows a case where an emitter follower circuit 52 composed of two bipolar transistors and a resistor is used as a buffer. LC element 100
However, since the bipolar transistor and the like can be formed on the same substrate although the structures thereof are slightly different, the whole including the emitter follower circuit 52 can be integrally formed as an LC element.

By thus providing the buffer on the output side, the signal level attenuated by the inductor portion (channel 22) of the LC element 100 or the like is restored by amplification, and an output signal with a good SN ratio can be obtained. become.

FIG. 34 is a diagram showing an example in which a level conversion circuit is connected to the output side. FIG. 1A shows a case where two emitter follower circuits 54 and 56 are connected in series as a level conversion circuit. FIG. 2B shows a case where two source follower circuits 58 and 60 are connected in series as a level conversion circuit.

As described above, by connecting the level conversion circuit to the output side, the signal level attenuated by the inductor portion of the LC element 100 or the like is amplified, and predetermined level conversion or level correction can be easily performed. it can.

Note that the point that these level conversion circuits can be integrally formed on the same substrate as the LC element 100 and the like is the same as in the case of the buffer described above.

FIG. 35 shows the LC device 1 of each of the above-mentioned embodiments.
It is a figure which shows an example at the time of comprising a voltage control oscillator (VCO) using 00 etc. As shown in the figure, an amplifier 61 is connected to the output side of the LC element 100 or the like of each of the above-described embodiments, and the output of this amplifier 61 is fed back to the input side of the LC element. The oscillation operation is performed by forming such a feedback loop. Moreover, the oscillation frequency is within a certain range by changing the gate voltage applied from the outside to the control electrode 24, that is, by changing the capacitance formed in a distributed constant and the resistance value of the channel 22 accordingly. Can be changed arbitrarily.

FIG. 36 shows the LC element 1 of each of the above-mentioned embodiments.
It is a figure which shows an example of a structure at the time of adding an input protection circuit to 00 etc. LC element 1 of each embodiment having a MOS structure
00, etc., when a high voltage generated by static electricity is applied to the control electrode 24, the insulating layer 28 interposed between the first electrode 10 connected to the control electrode 24 and the semiconductor substrate 30 is destroyed. To be done. Therefore, a protection circuit is required to prevent the insulating layer 28 from being damaged by this static electricity.

The protection circuit shown in the figure is composed of a plurality of diodes and resistors, and the first electrode 10
When a high voltage is applied to the control electrode 24 connected to
Current is bypassed to the operating power line side or the chassis ground side. In particular, the circuit shown in FIG. 10A is several hundreds of volts, and the circuit shown in FIG.
There is an electrostatic withstand voltage of V, and the protection circuit to be used can be appropriately selected according to the usage environment and the like.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the present invention.

For example, in each of the above-described embodiments, the enhancement type LC element 10 in which the channel 22 is formed when a predetermined gate voltage is applied to the control electrode 24.
Although 0 and the like have been described, a depletion type can also be used. That is, by injecting carriers (n-type impurities) into the region of the channel 22 shown in FIG.
The channel is formed. Thereby, the channel 22 is formed even when the gate voltage is not applied, or the relationship between the applied gate voltage and the channel width can be changed. Further, the carrier to be injected may be injected only into a part of the region along the first electrode, or all or part of the first electrode corresponding to the part into which the carrier is injected may be omitted. .

In each of the above embodiments, p-
While the second electrode 26 was formed in direct contact with the Si substrate 30 and the first electrode 10 was formed with the insulating layer 28 interposed, on the contrary, the first electrode 1 was formed.
0 may be formed by directly contacting the p-Si substrate 30, and the second electrode 26 may be formed by interposing the insulating layer 28. Also, the first and second electrodes 10,
Both 26 may be formed on the surface of the insulating layer 28.

In addition, the LC element of each embodiment in which the first and second electrodes 10 and 26 are formed on substantially the same surface is the first and the first on the p-Si substrate 30 which is a single layer of the p region. The second electrodes 10, 26, etc. are formed, but by forming a meandering shape or the like of the opposite conductivity type along these electrodes, it is possible to ensure the isolation between the adjacent channels 22. Good.

FIG. 37 shows the first and second electrodes 10, 2
6 is a diagram showing a cross-sectional structure in the case where a serpentine-shaped reverse conductivity type layer 66 substantially along 6 is formed, and corresponds to FIG. 2 described above. That is, as shown in FIG.
Reverse conductivity consisting of a meandering p region corresponding to the first and second electrodes 10 and 26 on a part of the substrate 64 consisting of regions.
The mold layer 66 is formed. In the LC element having such a structure, the control electrode 24 connected to the first electrode 10
When a predetermined gate voltage is applied to, a channel 22 is formed near the surface corresponding to the first electrode 10, as shown in FIG. Moreover, the conductivity is opposite to that of the substrate 64 .
By applying a reverse bias voltage to the mold layer 66, the meandering reverse conductivity type layers 66 are electrically separated from each other, and the channel 22 and the second electrode 26 are reliably distributed constant. Capacitors are formed.

In addition, in the LC element of each embodiment in which the first and second electrodes 10 and 26 are arranged so as to face each other, the first element is formed on the p-Si substrate 30 formed of a single layer in the p region.
Although the second electrodes 10 and 26 and the like are formed, they are formed between the adjacent first electrodes 10 or between the adjacent second electrodes 26.
Adjacent channels 2 are formed by forming a layer of opposite conductivity type.
It is also possible to ensure the isolation between the two.

FIG. 38 is a diagram showing a cross-sectional structure in the case where the opposite conductivity type layer is formed between the first electrodes 10 and between the second electrodes 26, and corresponds to FIG. 12 described above. That is, as shown in the figure, an opposite conductivity type layer composed of the n region 74 is formed on a part of the p-Si substrate 30. In the LC element having such a structure, the adjacent second electrode 2
Focusing on the p-Si substrates 30 connected to each other, the n regions 74 are formed therebetween so that they are electrically separated from each other and reliable isolation can be performed.

In addition, p-Si which is actually in a wafer state
Using the substrate 30, the first and second electrodes 10, 26
When manufacturing LC elements that face each other, p-Si
Considering that the specific resistance of the substrate 30 is higher than that of general metal, it is necessary to make the thickness of the p-Si substrate 30 thinner than that of the wafer. Further, in consideration of the fact that n-type wafers are generally easier to obtain, the structure shown in FIG. 39 may be adopted.

That is, as shown in FIG.
Etching in a meandering shape or the like is performed on one surface of the Si substrate 76, and the first or second electrode 26 is formed on the etched portion. Further, as shown in FIG.
A part of the n-Si substrate 76 is provided with the first and second electrodes 10,
P + regions 78 are formed so as to extend substantially along each of the regions 26, and then the backside of the n-Si substrate 76 corresponding to the second electrode 26 is etched, and finally the first region is formed.
And the second electrodes 10 and 26 are formed.

In each of the above embodiments, LC
Although the advantage that the element 100 and the like can be formed as a part of the LSI and the like has been described, it is not always necessary to form the element and the like as the LSI and the input / output electrode 18, after the LC element 100 and the like are formed on the semiconductor substrate. 20, each of the ground electrode 16 and the control electrode 24 is provided with a terminal, or the chemical liquid phase method shown in FIGS. 30 and 31 is used to provide a terminal to form a single element. You may do it. In this case, if a plurality of LC elements 100 and the like are simultaneously formed on the same semiconductor substrate and then the semiconductor substrate is separated and terminals are attached to each LC element and the like, mass production can be easily performed. Become.

In each of the above embodiments, the first
And the earth electrode 16 at the end of the second electrodes 10 and 26.
Although the source 12, and the drain 14 are provided, they are not necessarily provided at the outermost end, and the mounting positions may be shifted as needed after examining the frequency characteristics.

In each of the above embodiments, the first
Although the two input / output electrodes 18 and 20 are arranged in the vicinity of both ends of the electrode 10 of the above, and the two input / output electrodes 18 and 20 are approached by devising the shape of the first electrode 10. You may make it arrange | position.

For example, as shown in FIG.
1 and the drain 14 are arranged adjacent to each other, and FIG.
The first and second electrodes 10 of the LC device 100 shown in FIG.
One end of 26 is extended to the drain 14. Alternatively,
As shown in FIG. 41, the source 12 and the drain 14 are arranged adjacent to each other, and the LC element 10 shown in FIG.
The first and second electrodes 10 and 26 of 0 are folded back while maintaining the meandering shape.

As described above, by devising the shape of the first electrode 10 (or both the first and second electrodes 10 and 26), the positions of the two input / output electrodes 18 and 20 come close to each other, and The electrode 16, the control electrode 24, and the input / output electrodes 18, 20 can all be formed at substantially the same position. Therefore, it is possible to easily perform wiring at the time of attaching terminals, and it is possible to simplify the manufacturing process.

Further, the LC element and the like of each of the above-mentioned embodiments are
By changing the gate voltage applied to the control electrode 24, the resistance of the channel 22 and the capacitance of the capacitor formed in a distributed constant change, whereby the frequency characteristics of the entire LC element can be variably controlled. Therefore, by using the LC element 100 or the like as a part of the circuit, it is possible to easily configure a tuning circuit, a modulation circuit, an oscillation circuit, a filter and the like.

Further, the LC device 100 of each of the above-mentioned embodiments.
In the above description, the case where the pn junction layer 26 is formed on the p-Si substrate 30 has been described as an example. However, when another type of semiconductor such as germanium is used, or when an amorphous material such as amorphous silicon is used. May be

[0181]

[0182]

[0183]

[0184]

[0185]

[0186]

[0187]

[0188]

[0189]

[0190]

[0191]

[0192]

[0193]

[0194]

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201]

[0202]

[Brief description of drawings]

FIG. 1 is a plan view of an LC device according to a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along the line AA of FIG.

FIG. 3 is an enlarged sectional view taken along line BB of FIG.

4 is an enlarged cross-sectional view taken along line CC of FIG.

FIG. 5 is a diagram showing a cross-sectional structure in the meandering direction of the LC device of the first embodiment.

FIG. 6 is a diagram showing the principle of an inductor formed by meandering electrodes.

FIG. 7 is a diagram showing an equivalent circuit of the LC element of the first embodiment.

FIG. 8 is a diagram for explaining a resistance value of a channel.

FIG. 9 is a diagram showing a manufacturing process of the LC element of the first embodiment.

FIG. 10 is a diagram showing a modification of the LC element of the first embodiment.

FIG. 11 is a diagram showing a modification of the LC element of the first embodiment.

12 is an enlarged cross-sectional view taken along the line AA of the LC element shown in FIG.

FIG. 13 is a diagram showing a modification of the LC element of the first embodiment.

FIG. 14 is a plan view of an LC device according to a second embodiment.

FIG. 15 is a diagram showing an equivalent circuit of the LC device of the second embodiment.

FIG. 16 is a diagram showing a modification of the LC element of the second embodiment.

FIG. 17 is a diagram showing a modification of the LC element of the second embodiment.

FIG. 18 is a diagram showing a modification of the LC element of the second embodiment.

FIG. 19 is a plan view of an LC device according to a third embodiment.

FIG. 20 is a diagram showing an equivalent circuit of the LC element of the third embodiment.

FIG. 21 is a diagram showing a modification of the LC element of the third embodiment.

FIG. 22 is a plan view of an LC device according to a fourth embodiment.

FIG. 23 is a diagram showing an equivalent circuit of the LC device of the fourth embodiment.

FIG. 24 is a diagram showing a modification of the LC element of the fourth embodiment.

FIG. 25 is a plan view of an LC device according to a fifth embodiment.

FIG. 26 is a plan view of an LC device according to a fifth embodiment.

FIG. 27 is a diagram showing a modification of the LC element of the fifth embodiment.

FIG. 28 is a diagram showing a modification of the LC element of the fifth embodiment.

FIG. 29 is a diagram showing a modification of the LC element of the fifth embodiment.

FIG. 30 is a diagram schematically showing a case where terminals are attached using a chemical liquid phase method.

FIG. 31 is a diagram schematically showing a case where terminals are attached using a chemical liquid method.

FIG. 32 is an explanatory diagram of a case where the LC element of each example is formed as a part of an LSI or the like.

FIG. 33 is a diagram showing an example in which a buffer is connected to the output side of the LC element of each example.

FIG. 34 is a diagram showing an example in which a level conversion circuit is connected to the output side of the LC element of each example.

FIG. 35 is a diagram showing an example of a case where a voltage controlled oscillator is configured using the LC element of each example.

FIG. 36 is a diagram showing an example in which a protection circuit is connected to the input side of the LC element of each example.

FIG. 37 is a diagram showing a cross-sectional structure when an opposite conductivity type layer is formed in a semiconductor substrate.

FIG. 38 is a diagram showing a cross-sectional structure when an opposite conductivity type layer is formed in a semiconductor substrate.

FIG. 39 is a diagram showing a partial cross-section when a part of the substrate is etched.

FIG. 40 is a diagram showing a modification in which the positions of input / output electrodes are changed.

FIG. 41 is a diagram showing a modification in which the positions of input / output electrodes are changed.

[Explanation of symbols]

10 First electrode 12 sources 14 drain 16 Earth electrode 18, 20 Input / output electrodes 22 channels 24 Control electrodes 26 Second electrode 28 Insulation layer 30 p-Si substrate 32 depletion layer

Front page continuation (51) Int.Cl. ⁷ identification code FI H01P 1/203 H01G 4/40 321A H03H 7/01 (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 21/822 H01F 17 / 00 H01G 4/40 H01L 27/04 H01P 1/00 H01P 1/203 H03H 7/01

Claims (22)

(57) [Claims] 1. A non-spiral-shaped first electrode formed on a semiconductor substrate and functioning as a gate, and a non-spiral-shaped first electrode adjacent to the first electrode and formed on the semiconductor substrate. and second electrodes, said first electrode, an insulating layer formed between said semiconductor substrate, in the said semiconductor substrate, at both ends of the channel formed in correspondence to the first electrode A source and a drain formed, and an inductor formed by each of the channel formed corresponding to the first electrode and the second electrode, and a capacitor formed between them are distributed. An LC element characterized by using a channel which exists in a constant number and which is formed corresponding to at least the first electrode as a signal input / output path. 2. A non-spiral-shaped first electrode which is formed on a semiconductor substrate and functions as a gate, and a non-spiral-shaped first electrode which is formed on the semiconductor substrate adjacent to the first electrode. and second electrodes, the first electrode, an insulating layer formed between said semiconductor substrate, in the said semiconductor substrate, one end of the channel formed in correspondence to the first electrode A source or drain formed in the first electrode, an inductor formed by each of the channel formed corresponding to the first electrode and the second electrode, and a capacitor formed between them. An LC element, which is present in a distributed constant and uses the second electrode as a signal input / output path. 3. A non-spiral-shaped first electrode that is formed on one surface side of the semiconductor substrate and functions as a gate, and is formed on the other surface side of the semiconductor substrate and faces the first electrode. Second non-spiral shape formed in position
And the electrode, the first electrode, an insulating layer formed between said semiconductor substrate, in the said semiconductor substrate, formed at both ends of the channel formed in correspondence to the first electrode A source and a drain, and an inductor formed by each of the channel formed corresponding to the first electrode and the second electrode, and a capacitor formed between the inductor and the distributed constant. An LC element, which is present as a signal, and uses at least a channel formed corresponding to the first electrode as a signal input / output path. 4. A non-spiral-shaped first electrode that is formed on one surface side of the semiconductor substrate and functions as a gate, and is formed on the other surface side of the semiconductor substrate and faces the first electrode. Second non-spiral shape formed in position
And electrodes, said first electrode, an insulating layer formed between said semiconductor substrate, in the said semiconductor substrate, to one end of the channel formed in correspondence to the first electrode A source or drain formed, and an inductor formed by each of the channel formed corresponding to the first electrode and the second electrode, and a capacitor formed between them are distributed. An LC element which is present in a constant number and uses the second electrode as a signal input / output path. 5. The LC element according to claim 1, wherein the first and second electrodes have a meandering shape, a wavy shape, a curved shape, or a straight line shape. . 6. The LC according to claim 1, wherein a carrier is preliminarily injected into a position on the surface of the semiconductor substrate corresponding to the first electrode.
element. 7. The method according to claim 1, wherein the length of the second electrode is set to be longer or shorter than that of the first electrode so as to correspond to the first electrode. An LC element characterized in that a formed channel partially corresponds to the second electrode. 8. The semiconductor substrate according to claim 1, wherein a layer having a polarity opposite to that of the semiconductor substrate is formed along the first and second electrodes as the semiconductor substrate. An LC device characterized by being used. 9. The semiconductor substrate according to claim 3, wherein the semiconductor substrate is a layer having a polarity opposite to that of the semiconductor substrate, as a layer for isolating between the conductor portions of the first and second electrodes. An LC device using a semiconductor substrate on which a layer is formed. 10. The method according to claim 1, wherein the second electrode is divided into a plurality of pieces, and a part of each of the divided electrode pieces is electrically connected. Characteristic LC element. 11. The method according to claim 2, wherein the first electrode is divided into a plurality of portions, and each of a plurality of channels formed corresponding to each of the plurality of divided electrode pieces. An LC device characterized in that a source or a drain is provided at one end and a plurality of these sources or drains are electrically connected. 12. The method according to claim 1, wherein the source and the drain are formed at both ends of a channel formed corresponding to the first electrode, respectively. A first and second input / output electrodes, and a ground electrode electrically connected to one end of the second electrode, and a signal from one of the first and second input / output electrodes Is input and a signal is output from the other, and the earth electrode is connected to or grounded with a power source having a fixed potential. 13. The first and second input / output electrodes electrically connected to both ends of the second electrode according to any one of claims 2, 4 to 9 and 11, A ground electrode electrically connected to a source or a drain formed at one end of a channel formed corresponding to the electrode piece obtained by dividing the first electrode; An LC element, wherein a signal is input from any one of the input / output electrodes and a signal is output from the other, and the earth electrode is connected to or grounded with a power source having a fixed potential. 14. The method according to claim 1, wherein the source and the drain are formed at both ends of a channel formed corresponding to the first electrode, respectively. First and second input / output electrodes, and third and fourth input / output electrodes electrically connected to both ends of the second electrode, and formed corresponding to the first electrode. Used as a common mode type device having both a channel to be formed and the second electrode as a signal input / output path.
element. 15. The resistance of a channel formed corresponding to the first electrode according to claim 1, wherein the gate voltage applied to the first electrode is variably set. An LC element, wherein a value and a capacitance value of a capacitor formed in a distributed constant between the channel and the second electrode are variably controlled. 16. The LC element according to claim 1 is formed as a part of a substrate, and at least one of a channel formed corresponding to the first electrode and the second electrode is a signal line. Alternatively, the semiconductor device is characterized by being inserted into a power supply line and integrally molded. 17. The method according to claim 1, 3, 5 to 10, 12, and 14.
A semiconductor device, wherein a buffer for amplifying a signal output via the channel is connected to either one of the source and the drain of any one of the LC elements. 18. The method according to claim 1, 3, 5 to 10, 12, and 14.
2. A semiconductor device, wherein a level conversion circuit for changing a voltage level of a signal output via the channel is connected to either one of the source and the drain of any one of the LC elements. 19. An amplifier is connected in series to the signal input / output path of the LC element according to claim 1, and the amplified output is fed back to the signal input / output path and applied to the first electrode. A semiconductor device characterized in that a frequency is variably controlled by changing a gate voltage. 20. The LC according to claim 1, wherein at least one of the first and second electrodes is provided with a protection circuit for bypassing an overvoltage to an operating power supply line side or an earth side. element. 21. A first step of forming a source and a drain by partially implanting an impurity into a semiconductor substrate, and connecting the source and the drain via an insulating layer on the semiconductor substrate to function as an inductor. Forming a non-spiral-shaped first electrode for creating a channel
Moni, wherein on a semiconductor substrate, and it functions as an inductor adjacent to the first electrode, a second that form the second electrode of the non-spiral to produce a capacitor between said channel And a third step of forming a wiring layer electrically connected to each of the source and drain and the first and second electrodes, the method of manufacturing an LC element. A first step of forming a source or drain by 22. partially implanting impurities into the semiconductor substrate through an insulating layer on the semiconductor substrate, the one end in the vicinity of the source or drain A first electrode having a non-spiral shape for forming a channel positioned and functioning as an inductor is formed, and while functioning as an inductor adjacent to the first electrode on the semiconductor substrate , a second step that form the second electrode of the non-spiral to produce a capacitor between the wiring layer electrically connected to each of the source or drain and the first and second electrodes A third step of forming, and a method of manufacturing an LC element, comprising: