KR20070094277A - Inductor having high quality factor - Google Patents

Abstract

An inductor having a high quality factor is provided to reduce an area of an inductor pattern and a parasitic current quantity by gradually reducing a line width of the inductor pattern from the outside to the inside. An inductor having a high quality factor includes a first inductor pattern(221), and a second inductor pattern(222). The inductor is composed of a patterned conductor which has bent regions. An outer corner of each of bent regions is mitered. The first inductor pattern(221) is formed in a spiral shape which is wound around an upper part of a semiconductor substrate several times. The second inductor pattern(222) is connected to an internal end of the first inductor pattern(221). The second inductor pattern(222) is formed in an untwisted spiral shape which is bent several times. An outer corner of the region selected from the bent regions of the first and second inductor patterns(221,222) is mitered.

Description

Inductor having high quality factor

1 is a schematic plan view of an inductor according to the prior art

2 is a conceptual diagram illustrating an inductor having a high quality factor according to a first embodiment of the present invention;

3 is a schematic perspective view for explaining the cause of the parasitic capacitance generated

4 is a plan view showing a bent region of an inductor having a high quality factor according to a first embodiment of the present invention;

5 is a plan view illustrating a state in which an inductor having a high quality factor is patterned according to the first embodiment of the present invention;

FIG. 6 is a plan view illustrating a state in which an inductor having a high quality factor according to the first embodiment of the present invention is patterned differently from FIG. 5. FIG.

FIG. 7 is a schematic cross-sectional view illustrating an example for connecting an inner pattern and an outer pattern in the inductor of FIG. 6. FIG.

8 is a plan view illustrating a state in which an inductor having a high quality factor is patterned according to a second embodiment of the present invention;

<Description of the symbols for the main parts of the drawings>

100: inductor 110: bent area

120: corner 150,200: semiconductor substrate

151,201,202 Insulation layer 202a, 202b: Conductive via hole

221,222,230: Inductor pattern 310,320,330: Pattern

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inductor having a high quality factor. More particularly, by mitering the outer edges of the bent regions present in the inductor pattern, the Q factor can be improved by reducing the losses due to parasitic capacitance. By forming the inductor in a shape in which the line width of the pattern gradually decreases from the outer side of the inductor pattern to the inner side, a high quality coefficient that can reduce the area of the inner inductor pattern, reduce the amount of generated eddy currents, and increase the quality coefficient. An inductor having

Recently, according to the remarkable growth of the wireless mobile communication market, there are many developments of mobile communication terminals having excellent performance and low price.

In order to improve the performance of the wireless mobile communication terminal, the performance of the RF integrated circuit must be improved.

Such RF Frequency Integrated Circuits designs require an inductor for impedance matching.

This inductor is not only an inductance, but also a Q factor (Quality Factor) is an important device that determines the performance of the matching circuit, and is a basic device used throughout RF circuits such as voltage controlled oscillators (LCOs), LC filters, and matching circuits. .

Currently, commercially available inductor structures include meander-line and spiral inductors.

Among them, the structure having the larger inductor value in the same area is a spiral inductor.

Meander inductors are used to make inductors on low-cost substrates such as printed circuit boards with only a single metal layer, and inductors used in circuits of a single chip using a semiconductor process mainly use spirals.

The characteristic of this spiral structure is that like the solenoid type inductor, the spiral arm is wound on the top of the substrate several times in the same direction, thereby obtaining the maximum inductor value in the same area.

1 is a schematic plan view of an inductor according to the prior art, comprising: a first inductor pattern 21 formed in a spiral shape wound on an upper portion of a semiconductor substrate 10; It is composed of a second inductor pattern 22 formed in a spiral shape connected to the inner end of the first inductor pattern 21.

Here, the first inductor pattern 21 is a non-symmetrical pattern shown in FIG. 1, and the second inductor pattern 22 is a hatching pattern.

In this inductor, an RF signal is input to the first inductor pattern 21 and output to the second inductor pattern 22.

In addition, since the first and second inductor patterns 21 and 22 have a winding and unwinding shape in order to maintain a spiral shape, as shown in FIG.

In this overlapping region, an insulating film is interposed between the first and second inductor patterns 21 and 22 so that an electrical short does not occur.

The first and second inductor patterns 21 and 22 require a bent region to form a spiral shape, and the RF signal passes through the bent region at the shortest distance except the outer edge.

Therefore, the RF signal is hardly passed through the outer edges of the bent region, and parasitic capacitance is present in the substrate, resulting in a loss, causing a problem of degrading the quality factor.

Accordingly, the present invention provides an inductor having a high quality factor that can improve the Q factor by reducing the loss caused by parasitic capacitance by mitering the outer edge of the bent region present in the inductor pattern. There is a purpose.

Another object of the present invention is to form an inductor in a shape in which the line width of the pattern gradually decreases from the outer side of the inductor pattern to the inner side, thereby reducing the area of the inner inductor pattern, reducing the amount of eddy current generated, thereby increasing the quality factor. An inductor having a high quality factor is provided.

Preferred embodiments for achieving the above object of the present invention,

Patterned conductors,

The patterned conductor has bent regions,

An inductor having a high quality factor is provided, characterized in that the outer edges of each of the bent regions are mitered.

Another preferred aspect for achieving the above object of the present invention is

A first inductor pattern formed in a spiral shape that is bent and wound a plurality of times over the semiconductor substrate;

A second inductor pattern connected to an inner end of the first inductor pattern and formed in a spiral shape that is bent and released a plurality of times;

An inductor having a high quality factor is provided, wherein outer edges of selected areas among the bent regions of each of the first and second inductor patterns are mitered.

Another preferred aspect for achieving the above object of the present invention,

The inductor pattern is formed by bending a plurality of times from the first stage to the second stage on the semiconductor substrate in a spiral shape.

The first stage is outside the inductor pattern,

The second stage is inside the inductor pattern,

There is a third stage spaced apart from the first stage,

The third end is connected to the second end,

There is provided an inductor having a high quality factor, characterized in that the outer edges of selected areas of the bent regions of the inductor pattern are mitered.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 2 is a conceptual diagram illustrating an inductor having a high quality factor according to a first embodiment of the present invention, wherein the inductor 100 of the present invention is formed of a patterned conductor, and the patterned conductor is a bent region ( 110, and the outer edge 120 of each of the bent regions 110 is formed in a mitered pattern.

In general, the inductor 100 includes a region 110 bent in the inductor pattern to realize desired characteristics. Most of the RF signals passing through the curved region 110 are shown in FIG. 2. The shortest distance is transmitted from 'A' to 'B'.

Therefore, the outer edge 120 of the bent region 110 hardly passes the RF signal and thus does not contribute to the transmission of the RF signal, and there is a parasitic capacitance due to the substrate, resulting in loss.

For example, as shown in FIG. 3, when the insulating layer 151 is formed on the semiconductor substrate 150 and the inductor 100 having the bent region is formed on the insulating layer 151. In addition, a parasitic capacitor including the semiconductor substrate 150, the insulating layer 151, and the inductor 100 exists, and a loss occurs at the outer edge 120.

4 is a plan view illustrating a bent region of the inductor having a high quality factor according to the first embodiment of the present invention. As described with reference to FIG. 3, an outer edge of the bent region 110 of the inductor is mitered. The mitered surface may be formed into a curved surface as shown in FIG. 4, and may be formed into a flat surface as shown in FIG. 3.

FIG. 5 is a plan view showing a state in which an inductor having a high quality factor is patterned according to the first embodiment of the present invention. The inductor of the present invention is formed in a spiral shape in which a plurality of inductors are bent and wound on the semiconductor substrate 200. A first inductor pattern 221; And a second inductor pattern 222 which is connected to an inner end of the first inductor pattern 221 and is bent a plurality of times to form a spiral shape, and each of the first and second inductor patterns 221 and 222. The outer edges of the selected areas A, B, C, and D of the bent areas are mitered.

This inductor is patterned into a hexagonal shape.

Here, the first inductor pattern 221 is a non-symmetrical pattern shown in FIG. 5, and the second inductor pattern 222 is a hatching pattern.

Thus, in the first embodiment of the present invention, by mitering the outer edge of the bent region present in the inductor pattern, the Q factor can be improved by reducing the loss due to parasitic capacitance.

FIG. 6 is a plan view illustrating a state in which an inductor having a high quality factor is patterned differently from FIG. 5 according to the first embodiment of the present invention, and the inductor is formed at the first end 231 on the semiconductor substrate 200. The second end 232 is bent a plurality of times and wound in a spiral to form an inductor pattern 230. The first end 231 is located outside the inductor pattern 230, and the second end 232 is formed. Is inside the inductor pattern 230, and there is a third stage 233 spaced apart from the first stage 231, the third stage 223 is connected to the second stage 232 The outer edges of the selected regions E of the bent regions of the inductor pattern 230 are mitered.

Here, the inductor is patterned in a quadrangular shape.

FIG. 7 is a schematic cross-sectional view illustrating an example of connecting an inner pattern and an outer pattern in the inductor of FIG. 6, wherein a first insulating layer 201 is formed on a semiconductor substrate 200, and the first insulation is formed on the semiconductor substrate 200. A conductive line 240 is formed on a portion of the upper portion of the layer 201, a second insulating layer 202 is formed on the first insulating layer 201 and surrounds the conductive line 240. The inductor pattern shown in FIG. 6 is formed on the insulating layer 202, and each of the second and third ends of the inductor pattern formed on the second insulating layer 202 passes through the second insulating layer 202. If the conductive via holes 202a and 202b are connected to the conductive via holes 202a and 202b, and the conductive via holes 202a and 202b are connected to the conductive line 240, the inner and outer patterns of the inductor shown in FIG. 6 may be connected to each other. Will be.

8 is a plan view showing a patterned state of the inductor having a high quality factor according to the second embodiment of the present invention. In the second embodiment of the present invention, the inductor pattern is formed in a spiral shape, In order to implement, as illustrated in FIG. 8, a plurality of patterns 310, 320, 330 spaced apart from each other are wound.

When an RF signal flows through the spiral inductor, a magnetic field is formed in the inductor pattern, and magnetic flux lines a, b, c, d, e, and f are formed inside the inductor pattern to the outside of the inductor pattern.

At this time, the magnetic flux line density inside the inductor pattern becomes higher than the magnetic flux line density outside the inductor pattern, and more eddy current is generated in the inductor pattern having the higher magnetic flux line density.

This eddy current acts as a loss, lowering the quality factor.

Since the amount of eddy current is proportional to the area of the inductor, in the second embodiment of the present invention, if the line width of the inductor inner pattern is smaller than the line width of the inductor outer pattern, the amount of eddy current generated in the inner pattern of the inductor can be reduced.

Therefore, as shown in FIG. 8, when the inductor is formed in a shape in which the line width of the pattern gradually decreases from the outside of the inductor pattern to the inside (that is, W1> W2> W3), the area of the inductor pattern inside is reduced. The amount of generated eddy current is also reduced, which can increase the quality factor.

As described in detail above, the present invention has the effect of improving the quality factor by reducing the loss due to parasitic capacitance by mitering the outer edge of the bent region present in the inductor pattern.

In addition, the present invention by forming the inductor in a shape that the line width of the pattern gradually decreases from the outer side of the inductor pattern toward the inner side, thereby reducing the area of the inner inductor pattern, the amount of generated eddy currents, the effect of increasing the quality coefficient There is.

Although the invention has been described in detail only with respect to specific examples, it will be apparent to those skilled in the art that various modifications and variations are possible within the spirit of the invention, and such modifications and variations belong to the appended claims.

Claims (5)

Patterned conductors, The patterned conductor has bent regions, An inductor having a high quality factor, characterized in that the outer edges of each of the bent regions are mitered. A first inductor pattern formed in a spiral shape that is bent and wound a plurality of times over the semiconductor substrate; A second inductor pattern connected to an inner end of the first inductor pattern and formed in a spiral shape that is bent and released a plurality of times; And an outer edge of selected areas of the bent regions of each of the first and second inductor patterns is mitered. The inductor pattern is formed by bending a plurality of times from the first stage to the second stage on the semiconductor substrate in a spiral shape. The first stage is outside the inductor pattern, The second stage is inside the inductor pattern, There is a third stage spaced apart from the first stage, The third end is connected to the second end, And an outer edge of selected areas among the bent areas of the inductor pattern is mitered. The method according to any one of claims 1 to 3, The mitered surface is, An inductor having a high quality factor, characterized in that it is curved or flat. The method of claim 2 or 3, The inductor pattern is, An inductor having a high quality factor, characterized in that the line width of the pattern is gradually reduced from the outer side to the inner side.

Images