KR100689586B1 - Resistor of radio frequency device and method for manufacturing radio frequency device having the same - Google Patents

Abstract

The present invention suppresses the oxidation of TaNx in the atmosphere when forming a resistance using TaNx to suppress the increase in the resistance of parasitic-free RF elements and the resistance of contact resistance of such a resistor to function as designed. In order to provide a method for manufacturing an RF device, the present invention provides an RF device including an insulating film formed on a substrate and a metal layer including at least one first metal film containing 30 to 60 at% of nitrogen on the insulating film. To provide resistance.

Resistance, RF element, anti-oxidation, TaNx, nitrogen.

Description

RESISTOR OF RADIO FREQUENCY DEVICE AND METHOD FOR MANUFACTURING RADIO FREQUENCY DEVICE HAVING THE SAME}

1 is a graph showing the property of binding to oxygen when TaNx is generally exposed to the atmosphere.

2 is a cross-sectional view showing a method of forming a resistance element according to a first embodiment of the present invention.

Figure 3 is a TEM photograph showing the results of experiments to determine the degree of oxidation upon exposure to air of no nitrogen containing Ta at all.

4 is a TEM photograph showing the results of experiments to determine the oxidation degree upon exposure to TaNx formed by injecting nitrogen at 15 sccm.

5 is a TEM photograph showing the results of experiments to determine the degree of oxidation upon exposure to TaNx formed by injecting nitrogen at 30 sccm.

6A through 6F are cross-sectional views illustrating a method of manufacturing an RF device according to a second exemplary embodiment of the present invention.

FIG. 7 is a graph showing contact resistance values when TaNx having a different injection amount of nitrogen is not exposed to the air; FIG.

8 is a graph showing contact resistance values when TaNx having a different injection amount of nitrogen is exposed to the air;

<Explanation of symbols for main parts of drawing>

10, 100: semiconductor substrate 11: insulating film

12 metal layer 110 first insulating film

120: resistive layer 130, 180: etch stop film

140: photoresist pattern 145: etching process

150: second insulating film 160: via hole

170: contact plug 190: third insulating film

200: metal wiring

The invention RF (RF: Radio Frequency) to that of the resistor (resistor) and a RFID device having the same of the element according to the production method, in particular TaNx (x is a small number, such as 0.5, 1.0, such as Ta, Ta ₂ N, TaN _0.1 , Ta ₃ N ₅ , Ta ₄ N ₅ , TaN _0.8 Ta ₄ N and the like) and the resistance of the RF element formed by using the same, and a method of manufacturing an RF element having the same.

Recently, RF (Radio Frequency) devices have been actively applied in the field of wireless communication as their applications are expanded. Accordingly, in recent years, research has been actively conducted to develop high quality passive components to improve the quality of RF devices. Representative examples of passive devices include resistors, capacitors, and inductors. In addition, there are transformers, filters, mechanical switches, and electro-mechanical relays. Performs important functions such as bias, decoupling, switching noise suppression, filtering, tuning, feed-back, and termination.

Conventionally, polysilicon for gates has been used to form such passive elements, especially resistors. For example, poly silicon deposited on a semiconductor substrate was etched to simultaneously form a gate and a resistor. However, when the resistor is formed using the polysilicon for gate, there is a problem in that the RF property is degraded because the distance between the resistor and the semiconductor substrate is very close. Therefore, in order to solve this problem, researches on securing the distance between the resistor and the semiconductor substrate have been actively conducted in recent years. As a representative example, TaNx for metal wiring (x is a small number, for example, 0.5, 1.0, etc., and includes Ta, Ta ₂ N, TaN _0.1 , Ta ₃ N ₅ , Ta ₄ N ₅ , TaN _0.8 Ta ₄ N, etc.) It is a method of forming a resistance using.

However, TaNx has a property of being easily oxidized by binding to oxygen when exposed to the atmosphere as shown in FIG. 1. Therefore, the surface of the exposed TaNx is oxidized severely by etching the interlayer insulating film deposited on the TaNx to form a contact plug in the metallization process. As such, when the surface of TaNx is oxidized, the parasitic component of the resistance is increased, thereby greatly increasing the contact resistance. As a result, when TaNx is used to design a resistor, it cannot serve as a designed resistor.

Accordingly, the present invention has been proposed to solve the above-mentioned problems of the prior art, and when the resistance is formed by using TaNx, TaNx is suppressed from being oxidized in the air to provide a resistance of the RF element from which parasitic components are removed. Its purpose is.

In addition, the present invention has been proposed to solve the above problems of the prior art, to provide a method for manufacturing an RF element having a resistor that functions as designed by suppressing an increase in the contact resistance value of the resistor used in the RF element. Has a different purpose.

According to an aspect of the present invention, there is provided a resistance of an RF device including an insulating film formed on a substrate and a metal layer including at least one first metal film containing 30 to 60 at% of nitrogen on the insulating film. To provide.

In addition, the present invention according to another aspect for achieving the above object, the step of depositing a first insulating film on a substrate on which a semiconductor structure layer is formed, and the first insulating film containing 30 to 60 at% nitrogen Forming a resistive layer comprising at least one metal film, depositing an etch stop layer on the resist layer, depositing a second insulating film on the etch stop layer, and a surface of the resistive layer is uniform Forming a via hole in the second insulating film so as to be partially exposed; forming a contact plug in the second insulating film so as to fill the via hole; and forming a metal wiring on the second insulating film so as to be connected to the contact plug. It provides a method for manufacturing an RF device comprising the step.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. do.

Example 1

2 is a cross-sectional view illustrating a method of forming a resistance device according to a first exemplary embodiment of the present invention.

Referring to FIG. 2, in the resistor device according to the first embodiment of the present invention, after the insulating film 11 is deposited on the semiconductor substrate 10, nitrogen (N ₂ ) 30 to 30 is deposited on the insulating film 11. The metal layer 12 including at least one metal film containing about 60 at% (atomic%) is deposited by depositing. In this case, the metal film is formed by depositing a metal containing no nitrogen at all and then injecting nitrogen by sputtering.

Here, the metal layer 12 may be formed as a mono-layer of TaNx or a multi-layer of TaNx having a different nitrogen content ratio (at%). For example, in a single film of TaNx, Ta (a film containing no nitrogen, for example, a nitrogen content ratio of 0%) / TaNx bi-layer, and TaNx / Ta / TaNx triple-layer It is formed in any one form. In addition, since TaNx becomes a nonconductor when nitrogen content ratio exceeds 60at%, it is preferable to limit nitrogen content ratio to 60at% or less.

At this time, the nitrogen content ratio is determined by the nitrogen injection amount (sccm) (for example, when the nitrogen injection amount is 15sccm, the nitrogen content ratio is 25at% and when the nitrogen injection amount is 30sccm, the nitrogen content ratio is 50at%). Inject 30 sccm of nitrogen. As a result, it is possible to inhibit oxidation of TaNx that binds to oxygen when TaNx is exposed to the atmosphere. A detailed description thereof will be described below with reference to FIGS. 3 to 5.

3 to 5 are TEM photographs showing the results of experiments to determine the degree of oxidation of TaNx by exposing TaNx having a different nitrogen content ratio to the atmosphere for a predetermined time and then introducing it back into the chamber and depositing Ta. to be.

As shown in FIG. 3, when Ta is not contained in the air at all, Ta is further deposited to form Ta to form an oxide film having a predetermined thickness between Ta and Ta. In addition, as shown in FIG. 4, when TaNx injected with 15 sccm of nitrogen is exposed to the atmosphere, Ta is further deposited to form an oxide layer having a predetermined thickness between TaNx and Ta. On the other hand, as shown in FIG. 5, when TaNx injected with 30 sccm of nitrogen is exposed to the atmosphere and Ta is deposited again, an oxide film is not formed between TaNx and Ta.

3 to 5, it can be seen that TaNx is not oxidized in the air when the resistive element is formed using a metal layer including at least one TaNx containing about 30 to 60 at% of nitrogen.

Example 2

6A through 6F are cross-sectional views illustrating a method of manufacturing an RF device according to a second exemplary embodiment of the present invention. Here, the same reference numerals among the reference numerals illustrated in FIGS. 6A to 6F are the same components that perform the same function.

First, as shown in FIG. 6A, a first insulating layer 110 is deposited on a semiconductor substrate 100 on which a semiconductor structure layer (not shown) is formed. Here, the semiconductor structure layer includes a plurality of active elements such as transistors, passive elements such as resistors, capacitors, and inductors, and a plurality of memory cells, metal wirings, metal plugs, and the like.

Subsequently, the resistive layer 120 including at least one metal film containing about 30 to 60 at% of nitrogen is deposited on the first insulating film 110. In this case, the metal film is formed by depositing a metal containing no nitrogen at all and then injecting nitrogen in a sputtering method. In addition, the resistive layer 120 may be formed as a mono-layer of TaNx or a multi-layer of TaNx having a different nitrogen content ratio (at%). For example, it is formed in the form of any one of a single layer of TaNx, a bi-layer of Ta (nitrogen-free nitrogen) / TaNx, and a triple-layer of TaNx / Ta / TaNx.

Subsequently, an etch stop layer 130 is deposited on the resistive layer 120. In this case, the etch stop layer 130 is formed of silicon nitride (SiN).

Subsequently, as shown in FIG. 6B, a photoresist (not shown) is coated on the etch stop layer 130, followed by an exposure and development process to form a photoresist pattern 140.

Subsequently, an etching process 145 using the photoresist pattern 140 as a mask is performed to etch the etch stop layer 130 and the resistance layer 120. As a result, a portion of the first insulating layer 110 is exposed.

Subsequently, as shown in FIG. 6C, a strip process is performed to remove the photoresist pattern 140.

Subsequently, a second insulating layer 150 is deposited on the etch stop layer 130 including the exposed first insulating layer 110. In this case, the second insulating layer 150 is formed of an oxide-based material. For example, the second insulating layer 150 may include an HDP (High Density Plasma) oxide film, a Boron Phosphorus Silicate Glass (BPSG) film, a Phosphorus Silicate Glass (PSG) film, a Plasma Enhanced Tetra Ethyle Ortho Silicate (PETOS) film, and a Plasma Enhanced Chemical (PECVD) film. A single layer film or a laminate thereof is formed by using any one of a vapor deposition (USG) film, a USG (Un-doped Silicate Glass) film, a FSG (Fluorinated Silicate Glass) film, a carbon doped oxide (CDO) film, and an organic Silicate Glass (OSG) film. It is formed of a laminated film.

Subsequently, an etching process using a predetermined photoresist pattern (not shown) as a mask is performed to etch the second insulating layer 150 and the etch stop layer 130. As a result, the via hole 160 exposing a portion of the resistance layer 120 is formed.

Subsequently, although not shown in the figure, a strip process is performed to remove the photoresist pattern.

Subsequently, as illustrated in FIG. 6E, TaNx or copper (Cu) is deposited on the second insulating layer 150 to fill the via holes 160 (see FIG. 6D). At this time, TaNx is to contain 0 to 60at% of nitrogen.

Subsequently, a chemical mechanical polyshing (CMP) planarization process is performed to planarize TaNx or copper. As a result, a contact plug 170 in which the via hole 160 is embedded is formed.

Subsequently, as illustrated in FIG. 6F, after the etch stop layer 180 is deposited on the second insulating layer 150 including the contact plug 170, the third insulating layer 190 is formed on the etch stop layer 180. Deposit.

Next, an etching process using a predetermined photoresist pattern (not shown) as a mask is performed to etch the third insulating layer 190 and the etch stop layer 180. As a result, a trench (not shown) for exposing the contact plug 170 is formed.

Subsequently, a metal material is deposited on the third insulating layer 190 to fill the trench to form the metal wiring 200. As a result, the metal wire 200 is electrically connected to the resistance layer 120 through the contact plug 170.

That is, according to the second preferred embodiment of the present invention, the RF device is manufactured by using the resistor layer including at least one metal film containing 30 to 60 at% of nitrogen, so that the oxide film is formed on the resistor layer even when the resistor layer is exposed to the air. This will not be formed. Therefore, the desired resistance characteristics can be obtained by functioning as the resistor is designed without increasing the contact resistance value of the resistance used in the RF element.

FIG. 7 is a graph showing contact resistance values when TaNx having different amounts of nitrogen is not exposed to the atmosphere, and FIG. 8 is a graph showing contact resistance values when TaNx having different amounts of nitrogen are exposed to the atmosphere. .

Referring to FIGS. 7 and 8, it can be seen that when TaNx is not exposed to the air, the contact resistance value is not related to the injection amount of nitrogen. When TaNx is exposed to the air, the contact resistance value is large depending on the injection amount of nitrogen. It can be seen that the change. That is, as in the first and second preferred embodiments of the present invention, if the resistance is formed by using TaNx containing 30 to 60 at% of nitrogen, the contact resistance value is higher than when using TaNx containing less than 30 at% of nitrogen. This is greatly reduced.

Although the technical idea of the present invention has been described in detail according to the above preferred embodiment, it should be noted that the above-described embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

As described above, according to the present invention, by forming a resistor using a metal layer containing at least one TaNx containing about 30 to 60 at% of nitrogen, the resistor is not oxidized even when exposed to the atmosphere. Thus, the parasitic component of the RF resistive element can be effectively removed.

In addition, according to the present invention, an RF device is manufactured using a resistive layer containing at least one of TaNx containing 30 to 60 at% of nitrogen, so that an oxide film is not formed on the resistive layer even when the resistive layer is exposed to air. Therefore, the desired resistance characteristics can be obtained by functioning as the resistor is designed without increasing the contact resistance value of the resistance used in the RF element.

Claims (9)

An insulating film formed on the substrate; And A metal layer including at least one first metal film containing 30 to 60 at% of nitrogen on the insulating film. Resistance of RF element consisting of. The method of claim 1, The metal layer is a lamination port of the second metal film / the first metal film that does not contain nitrogen Or a laminated structure of the first metal film / second metal film / the first metal film. Resistance of the RF element. The method according to claim 1 or 2, And wherein the first metal film is TaNx and the second metal film is Ta. Depositing a first insulating film on the substrate on which the semiconductor structure layer is formed; Forming a resistive layer including at least one first metal film containing 30 to 60 at% of nitrogen on the first insulating film; Depositing an etch stop layer on the resistive layer; Depositing a second insulating film on the etch stop layer; Forming a via hole in the second insulating layer to partially expose the surface of the resistive layer; Forming a contact plug in the second insulating layer to fill the via hole; And Forming a metal wiring on the second insulating layer to be connected to the contact plug Method of manufacturing an RF device comprising a. The method of claim 4, wherein The resistive layer may be formed of a lamination structure of a second metal film / first metal film containing no nitrogen or a lamination structure of the first metal film / the second metal film / the first metal film. Way. The method according to claim 4 or 5, And the first metal film is TaNx, and the second metal film is Ta. The method according to claim 4 or 5, And the contact plug is formed using TaNx or Cu. The method of claim 7, wherein The TaNx is a method of manufacturing an RF device containing 1 to 60 at% nitrogen. The method according to claim 4 or 5, The etching stop layer is a method of manufacturing an RF element formed using SiN.

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