JPH08288464A - Structure of rc circuit element - Google Patents

Abstract

PURPOSE: To reduce an area occupied by an RC circuit element by overlapping a capacitor over a resistor on a semiconductor layer. CONSTITUTION: An RC circuit element 1 is provided by laminating a capacitor 12, which is composed of a first metal layer 4, a second metal layer 5 and a dielectric layer 6, through an insulator layer 7 on a resistor 3 formed on a semiconductor substrate 2. A resistor 3 and a first metal layer 4 are electrically connected in a second opening 10 provided on the insulator layer 7, and the capacitor 12 and a resistor 13 are connected in series. Thus, the RC circuit element is manufactured on a small area, high integration of an integrated circuit, etc., is allowed and circuit components are downsized.

Description

Detailed Description of the Invention

[0001]

This invention relates to the structure of RC circuit elements. More specifically, it relates to the structure of an RC circuit element in which a capacitor (C) and a resistor (R) overlaid with a pair of conductive materials via an insulating layer are formed on a semiconductor layer.

[0002]

2. Description of the Related Art Microwave integrated circuits (monolithic micr
FIGS. 7A and 7B show the structure of a conventional RC circuit element 51 in which a MIM (metal-insulator-metal) capacitor and a resistor are formed on an owave IC). FIG. 7A shows the planar structure of the RC circuit component, but the planar structure does not show the dielectric layer 58, and the solid line in the drawing shows the state immediately before the formation of the dielectric layer 58. Shows the state after the dielectric layer 58 is formed (the same applies in FIG. 8). This RC circuit element 51
Is a capacitor 61 as shown in the equivalent circuit diagram of FIG.
And the resistor 55 are connected in series, and can be manufactured as follows. Resistor 5 on semiconductor substrate 52
5, the insulator layer 53 is formed, and the opening 54 is formed. Next, on the insulator layer 53, a first metal layer 56 electrically connected to one end of the resistor 55 is formed in series with the resistor 55, and the other end of the resistor 55 is electrically connected to the resistor 55. The electrode lead wire 57 that is electrically connected is formed. The solid line in FIG. 7A shows the planar structure at this time. Next, a dielectric layer 58 is formed on the semiconductor substrate 52 so as to cover at least the upper surface of the first metal layer 56, and then, as shown in FIG.
As shown by the imaginary line in (a), the second metal layer 59 and the electrode lead-out line 60 are provided so as to face the first metal layer 56 and the dielectric layer 5 is formed.
Form on 8.

An RC circuit element 51 which is another conventional example.
8 and 9 show the structure of the RC circuit element 51,
As shown in the equivalent circuit diagram of FIG. 10, the resistor 55 and the capacitor 61 are connected in parallel. 8A and 8B show a planar structure of the RC circuit element 51. FIG. 9A is a sectional view taken along the line AA of FIG. 8, and FIG. 9B is a sectional view taken along the line BB of FIG. FIG. 9 (c) is a sectional view taken along the line CC of FIG. The RC circuit element 51 can be manufactured as follows. A resistor 55 is formed on the semiconductor substrate 52, then an insulator layer 53 is formed, and an opening 54 is formed.
Next, on the insulator layer 53, the resistor 55 is attached to one end of the resistor 55.
A first metal layer 56 electrically connected to the resistor 55 is formed in parallel with the resistor 55, and an electrode lead wire 57 is formed.
An electrode lead wire 60 is formed on the other end of the resistor 55. Further, the electrode lead wire 60 is formed with a connection portion 62 for drawing out the second metal layer 59. The solid line in FIG. 8 shows the planar structure at this time. Next, a dielectric layer 58 is formed on the semiconductor substrate 52 so as to cover at least the first metal layer 56, and then a second metal layer 56 is formed so as to face the first metal layer 56 as shown by an imaginary line in FIG. The layer 59 is formed on the dielectric layer 58, and the second metal layer 59 and the connection portion 62 are electrically connected to each other through the opening 63 provided in the dielectric layer 58.

[0004]

However, in these RC circuit elements, since the capacitors and the resistors are arranged side by side on the semiconductor substrate, respectively, the area of the semiconductor substrate is occupied. , The RC circuit element was getting larger.

The present invention has been made in view of the drawbacks of the above conventional examples, and an object thereof is to provide an RC circuit element in which a capacitor and a resistor are formed on a semiconductor layer. Occupying less area.

[0006]

The structure of an RC circuit element according to the present invention is a structure of an RC circuit element comprising a capacitor and a resistor in which both surfaces of an insulator layer are sandwiched between electrode layers, and a semiconductor layer. The resistor formed on the surface of or above and the capacitor formed above the semiconductor layer are arranged so as to overlap each other.

In this RC circuit element, two or more resistors may be provided in the same layer, or two or more capacitors may be provided.

[0008]

In the structure of the RC circuit element of the present invention, since the resistor and the capacitor are arranged on the semiconductor layer so as to overlap with each other, the RC circuit element can be manufactured in a small area, and the integrated circuit can be manufactured. High integration can be achieved, and circuit components can be downsized.

Further, by providing two or more resistors or two or more capacitors and connecting the resistors and the capacitors in series or in parallel, various circuit configurations can be realized, and abundant RC is provided. A circuit element can be manufactured. If two or more resistors and capacitors are provided in the same layer, the number of manufacturing process steps can be reduced even when the number of elements increases.

[0010]

1A and 1B show the structure of an RC circuit element 1 according to an embodiment of the present invention. 1A shows the planar structure of the RC circuit element 1, but the dielectric layer 6 is not shown in the planar structure of FIG. 1A, and the solid line in FIG. 1A forms the dielectric layer 6. 1A, the imaginary line in FIG. 1A shows the state after the dielectric layer 6 is formed (the same applies to the drawings showing the planar structure hereinafter). This RC circuit element 1
In the above, the first metal layer 4, the second metal layer 5, and the dielectric layer 6 are formed on the upper surface of the resistor 3 formed on the semiconductor substrate 2.
The capacitor 12 composed of and is laminated via the insulator layer 7, and the second opening 10 provided in the insulator layer 7 is formed.
Inside, the resistor 3 and the first metal layer 4 are electrically connected, and the capacitor 12 and the resistor 3 are connected in series as shown in the equivalent circuit diagram of FIG. 1 (c). The RC circuit element 1 can be manufactured, for example, as follows.
First, as shown in FIG. 2A, the resistor 3 is formed in a predetermined region on the semiconductor substrate 2 (or may be a laminated semiconductor layer), and the resistor 3 is covered to form the semiconductor substrate. An insulator layer 7 is formed on the second layer 2. The resistor 3 may be formed on the surface of the semiconductor substrate 2 by ion implantation. Next, a first opening 8 and a second opening 10 are provided at both ends of the resistor 3, and an electrode lead wire 9 electrically connected to one end of the resistor 3 is provided in the first opening 8 as an insulator. Formed on layer 7. Further, the first metal layer 4 which is electrically connected to the other end of the resistor 3 in the second opening 10 is formed on the insulator layer 7 above the resistor 3 (FIG. 2B). At this time, the first metal layer 4 is formed in the same step as the electrode lead wire 9 so as not to contact the electrode lead wire 9. What is indicated by the solid line in FIG. 1A is the planar structure at this time. Next, a dielectric layer 6 is formed on almost the entire surface of this structure (see FIG.
(C)), and finally, as shown by an imaginary line in FIG.
The RC circuit element 1 is manufactured by forming the electrode lead wire 11 which is formed on the upper surface and electrically connected to the second metal layer 5 (FIG. 2D).

Since this RC circuit element 1 has a structure in which the capacitor 12 is laminated above the resistor 3 formed on the semiconductor substrate 2, it is smaller than the conventional RC circuit element 51. The RC circuit element 1 can be manufactured in the occupied area. For example, when the occupied area of the capacitor 12 and the occupied area of the resistor 3 are equal, the conventional RC circuit element 51
Compared with the above, the occupying area can be about 50% or less, the RC circuit element 1 can be provided with a size of about 1/2 of the conventional size, and it can contribute to the improvement of the degree of integration in the semiconductor circuit.

3 (a) and 3 (b) are a plan structural view and a sectional structural view of an RC circuit element 1 which is another embodiment of the present invention. In this RC circuit element 1, Figure 3
As shown in the equivalent circuit diagram of (c), the capacitor 12 and the resistor 3 are connected in parallel. The RC circuit element 1 can be manufactured, for example, as follows. First, FIG.
As shown in (a), the resistor 3 is formed in a predetermined region on the semiconductor substrate 2, and the semiconductor substrate 2 is covered with the resistor 3.
An insulator layer 7 is formed on top. Next, the first opening 8 and the second opening 10 are provided at both ends of the resistor 3, the first metal layer 4 is formed on the insulator layer 7, and the first opening 8 and the second opening 10 are formed in the openings 8 and 10. The resistor 3 and the first metal layer 4 are electrically connected. Further, an electrode lead wire 9 electrically connected to the first metal layer 4 is formed on the insulator layer 7 (FIG. 4B). Next, in the second opening 10, the first metal layer 4 is annularly removed by etching or the like along the outer edge of the second opening 10.
The resistor 3 in the second opening 10 by a region separated from
The connection portion 13 is formed to electrically connect with (see FIG. 4).
(C)). At this time, the connection portion 13 and the first metal layer 4 are insulated. What is indicated by the solid line in FIG. 3A is the planar structure at this time. The dielectric layer 6 is formed on almost the entire surface of the structure thus formed. After that, the third opening 14 is provided in the dielectric layer 6 at the connecting portion 13, and the third opening 14 is provided.
A part of the upper surface of is exposed again (FIG. 4D). Finally, as shown in the phantom line in FIG. 3A, the first layer is formed on the dielectric layer 6.
To form a second metal layer 5 facing the metal layer 4 of
The RC circuit element 1 can be manufactured by forming the electrode lead wire 11 electrically connected to the connection portion 13 in the opening 14 and electrically connected to the second metal layer 5 on the insulator layer 7. (FIG.4 (e)).

Even in this RC circuit element 1, since the capacitor 12 and the resistor 3 are laminated via the insulator layer 7, the area occupied by the RC circuit element 1 can be small. Further, as compared with the conventional RC circuit element 51, the metal region for connecting the capacitor 12 and the resistor 3 is reduced, and the parasitic component due to this metal region can be eliminated.

FIG. 5 (a) is a plan structural view of an RC circuit element 1 which is still another embodiment of the present invention.
What is shown in (b) is a cross-sectional structure diagram. This RC circuit element 1 has a structure in which a first resistor 3a is connected in series to a parallel circuit of a second resistor 3b and a capacitor 12, as shown in the equivalent circuit diagram of FIG. 5 (c). The RC circuit element 1 can be manufactured as follows. After the two resistors 3a and 3b are integrally formed on the semiconductor substrate 2,
The insulator layer 7 is formed so as to cover the two resistors 3a and 3b. Next, on the side opposite to the resistor 3b, the resistor 3
A first opening 8 is provided at one end of a, and an electrode lead wire 9 electrically connected to the resistor 3a in the opening 8 is formed on the insulator layer 7. In addition, the first metal layer 4 is formed on the insulator layer 7 in the same step as the electrode lead wire 9 so as not to come into contact with the electrode lead wire 9, and electrically connected to the resistor 3b in the second opening 10. And is electrically connected to the resistors 3a and 3b in the fourth opening 15. Then the second
In the opening 10, the first metal layer 4 is annularly removed along the outer edge thereof by etching or the like to form the connection portion 13 by the region separated from the metal layer 4. Figure 5
The solid line in (a) shows the planar structure at this time.
After the dielectric layer 6 is formed on almost the entire area of the structure thus formed, the third opening 1 is located inside the second opening 10.
4 is provided on the dielectric layer 6, and a part of the upper surface of the connecting portion 13 is exposed again. Finally, as shown by the imaginary line in Fig. 5 (a),
A second metal layer 5 is formed on the dielectric layer 6 so as to face the first metal layer 4 to electrically connect to the connection portion 13 in the third opening 14, and the second metal layer 5 is also formed. Forming an electrode lead wire 11 electrically connected to the insulator layer 7 on the insulator layer 7;
The C circuit element 1 can be manufactured. In this example, 2
The capacitor 12 is formed above the two resistors 3a and 3b to form a two-layer structure. In this case, the second resistor 3b is formed above the first resistor 3a, and the second resistor 3b is further formed.
A capacitor 12 may be formed above b to form a three-layer structure, but the manufacturing process becomes complicated. In this respect, if the resistors 3a and 3b are formed in the same layer, the two resistors 3a and 3b can be simultaneously formed in the same step, so that the RC circuit element 1 can be manufactured by simplifying the manufacturing process.

Further, FIG. 6 shows another embodiment of R.
The C circuit element 1 is shown. In this RC circuit element 1, as shown in the equivalent circuit diagram of FIG. 6C, the first capacitor 1 is provided in the parallel circuit of the second capacitor 12b and the resistor 3.
2a are connected in series. This RC circuit element 1 is
It can be manufactured as follows. The insulator layer 7 is formed so as to cover the resistor 3 formed on the semiconductor substrate 2. A first opening 8 and a second opening 10 are provided in the insulating layer 7 at both ends of the resistor 3, and the first opening 8 and the second opening 10 are provided on the insulating layer 7.
Forming a metal layer 4 in the first opening 8 and in the second opening 1
Within 0, the resistor 3 and the first metal layer 4 are electrically connected to each other. Next, in the second opening 10, the first metal layer 4 is annularly removed along the outer edge portion thereof, and then the connection portion 13 is formed.
To form. What is indicated by the solid line in FIG. 6A is the planar structure at this time. The dielectric layer 6 is formed on almost the entire surface of the structure thus formed. After that, the third opening 14 is provided in the dielectric layer 6 at the second opening 10 to form the connecting portion 13
Re-expose a part of the upper surface of. Finally, as shown by the phantom line in FIG. 6A, the second metal layer 5a is formed on the dielectric layer 6.
And the third metal layer 5b are electrically separated from each other, and the third metal layer 5b is electrically connected to the connection portion 13 in the third opening 14. In this way, the RC circuit structure 1 can be manufactured by forming the first capacitor 12a and the second capacitor 12b above the resistor 3. Reference numeral 9 is an electrode lead wire for leading out the first capacitor 12a, and 11 is an electrode lead wire for leading out the second capacitor 12b. Also in this embodiment, the capacitor 12a, the resistor 3 and the capacitor 12b may be laminated to form a three-layer structure, but if the two capacitors 12a and 12b are formed in the same layer as in this embodiment, they are the same. Since the two capacitors 12a and 12b can be simultaneously formed by the steps, the manufacturing process can be simplified and the RC circuit element 1 can be manufactured.

As described above, the structure of the RC circuit element of the present invention is not limited to the series circuit or parallel circuit of the capacitor and the resistor, but the series circuit of the RC parallel circuit and the resistor or the series circuit of the RC parallel circuit and the capacitor. It can be applied to various RC circuits. Further, if two or more resistors and capacitors are provided in the same layer, the number of steps in the manufacturing process can be reduced even if the number of elements increases.

[0017]

According to the present invention, series and parallel RC circuit elements can be manufactured with a small occupation area.
It is possible to reduce the size of the integrated circuit and improve the degree of integration.

[Brief description of drawings]

FIG. 1 (a) is a plan structural view in which an RC circuit element according to an embodiment of the present invention is partially omitted, and FIG. 1 (b) is a sectional structural view thereof.
(C) is the equivalent circuit diagram.

2A to 2D are explanatory views showing a method for manufacturing the RC circuit element of the above.

FIG. 3A is a plan structural view in which an RC circuit element according to another embodiment of the present invention is partially omitted, FIG. 3B is a sectional structural view thereof, and FIG. 3C is an equivalent circuit diagram thereof.

4 (a) to 4 (e) are explanatory views showing a method for manufacturing the RC circuit element of the above.

FIG. 5 (a) is an RC according to still another embodiment of the present invention.
FIG. 2 is a plan view showing a circuit element with a part thereof omitted, FIG.

FIG. 6 (a) is an RC according to still another embodiment of the present invention.
FIG. 2 is a plan view showing a circuit element with a part thereof omitted, FIG.

FIG. 7A is a plan structural view in which a part of an RC circuit element of a conventional example is omitted, FIG. 7B is a sectional structural view thereof, and FIG. 7C is an equivalent circuit diagram thereof.

FIG. 8 is a plan structural view in which a part of an RC circuit element, which is another conventional example, is omitted.

9 (a) is a sectional structural view taken along the line AA of FIG.
8B is a sectional structure view taken along line BB of FIG. 8, and FIG. 9C is a sectional structure view taken along line CC of FIG.

FIG. 10 is an equivalent circuit diagram of the RC circuit element of the above.

[Explanation of symbols]

 2 semiconductor substrate 3 resistor 4 first metal layer 5 second metal layer 6 dielectric layer 7 insulator layer

Claims (3)

[Claims] 1. A structure of an RC circuit element comprising a resistor and a capacitor having both surfaces of an insulating layer sandwiched between electrode layers, the resistor being formed on the surface of or above a semiconductor layer, and a semiconductor. A structure of an RC circuit element, wherein the capacitor formed above a layer is arranged so as to overlap. 2. The structure of the RC circuit element according to claim 1, wherein two or more resistors are provided in the same layer. 3. The structure of the RC circuit element according to claim 1, wherein two or more capacitors are provided in the same layer.