JP2004158880A - Manufacturing equipment for semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the properties of an ozone TEOS (tetraethylorthosilicate) film formed on a capacitive element. <P>SOLUTION: A substrate holder 302 is provided inside a chamber 300 that holds a semiconductor substrate 301. Gaseous TEOS supplied from a TEOS supply pipe 314 and ozone supplied from an ozone supply pipe 323 are mixed, and supplied to one end of an ozone TEOS supply pipe 330 while gaseous HMDS (hexamethyldisilazane) is supplied to one end of an HMDS supply pipe 344 after its flow rate is adjusted. The ozone TEOS and HMDS supplied are supplied individually or mixed from a raw material supply pipe 351 to the inside of the chamber 300, and then supplied from a raw material supply section 352 onto the surface of a semiconductor substrate 301. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to an apparatus for manufacturing a semiconductor device including a capacitor having a dielectric film having a high dielectric constant (hereinafter, referred to as a high dielectric film) or a capacitor insulating film formed of a ferroelectric film.

  In recent years, consumer electronic devices have become more sophisticated as the trend toward higher speed and lower power consumption of microcomputers and the like has been promoted, and semiconductor devices used in consumer electronic devices include semiconductors constituting the semiconductor devices. The miniaturization of elements has been rapidly progressing.

  Along with this, unnecessary radiation, which is electromagnetic wave noise generated from electronic equipment, has become a major problem. As a measure to reduce this unnecessary radiation, a large capacity capacitor having a capacitive insulating film made of a high dielectric film or a ferroelectric film has been developed. The technology of incorporating such a capacitive element in a semiconductor integrated circuit device is receiving attention.

  Also, with the high integration of the dynamic RAM, a technique of using a high-dielectric film or a ferroelectric film instead of a conventional silicon oxide or silicon nitride as a capacitive insulating film of a capacitor has been widely studied. Have been.

  Furthermore, research and development on ferroelectric films having spontaneous polarization characteristics have been actively pursued with the aim of putting a non-volatile RAM capable of operating at low voltage and writing or reading at high speed to practical use.

  Therefore, it is important to develop a method for realizing high integration of a semiconductor device without deteriorating the characteristics of a capacitor.

  Hereinafter, a conventional method for manufacturing a semiconductor device will be described with reference to FIGS. 11 (a) to 11 (c) and FIGS. 12 (a) and 12 (b).

  First, as shown in FIG. 11A, after an element isolation region 11 and a gate electrode 12 of an FET are formed on a semiconductor substrate 10, an impurity diffusion layer of an FET (not shown) is formed on the surface of the semiconductor substrate 10. After that, an insulating film 13 is deposited over the entire surface of the element isolation region 11 and the gate electrode 12. Thereafter, a capacitor lower electrode 14 made of a platinum film or the like, a capacitor insulating film 15 made of a high dielectric film or a high dielectric film, and a capacitor upper electrode made of a platinum film or the like above the element isolation region 11 on the insulating film 13. 16 are formed. In addition, a capacitive element is constituted by the capacitive lower electrode 14, the capacitive insulating film 15, and the capacitive upper electrode 16.

  Next, as shown in FIG. 11B, after forming a first protective film 17 so as to cover the capacitive element, a contact hole 18 of the FET is formed in the insulating film 13 and a first protective film 17 is formed in the first protective film 17. A contact hole 19 for a capacitor is formed. Next, after depositing a metal film such as a titanium film or an aluminum alloy film over the entire surface of the insulating film 13 and the first protection film 17, the impurity diffusion layer of the FET is formed by patterning the metal film. Alternatively, a first wiring layer 20 connected to the capacitor upper electrode 16 is formed, and thereafter, the first wiring layer 20 is subjected to a heat treatment.

  Next, as shown in FIG. 11C, a silicon oxide film is formed on the entire surface of the first wiring layer 20 and the capacitor by plasma TEOS (Tetraetylorthosilicate: hereinafter, abbreviated as TEOS). An interlayer insulating film (plasma TEOS film) 21 is deposited. The thickness of the interlayer insulating film 21 is set to be about 1 μm or more above the first wiring layer 20 on the capacitor upper electrode 17 in consideration of flattening by reflow.

  Next, after the interlayer insulating film 21 is planarized, a contact hole is formed in the interlayer insulating film 21. Thereafter, as shown in FIG. A second wiring layer 22 connected to the second wiring layer 20 is formed.

  Next, as shown in FIG. 12B, a second protective film 23 is deposited on the interlayer insulating film 21 so as to cover the second wiring layer 22.

  However, according to the conventional structure, the interlayer insulating film 21 is made of a plasma TEOS film, and the interlayer insulating film 21 has a small stress applied to the capacitive element and tends to be compressive. There is a problem that polarization does not sufficiently appear. Therefore, the characteristics of the capacitive element are not sufficient.

  Therefore, as shown in Japanese Patent Publication No. 2846310, we use a silicon oxide film (hereinafter referred to as an ozone TEOS film) formed by an ozone TEOS method instead of the plasma TEOS film as the interlayer insulating film 21. The technology used was proposed.

When an ozone TEOS film is used as the interlayer insulating film 21, stress acting on the capacitor can be increased, so that characteristics of the capacitor are improved.
Japanese Patent Publication No. 2846310

  However, the use of the ozone TEOS film as the interlayer insulating film has caused a new problem as described below. That is, there is a problem that a defect such as a hole is partially formed in the interlayer insulating film made of the ozone TEOS film, and that the film formation rate of the ozone TEOS film is different due to the difference in the type of the base film. did.

  When such a problem occurs, the quality of the semiconductor integrated circuit device is deteriorated, and the stress applied to the capacitor is not uniform, so that the characteristics of the capacitor cannot be improved.

  In view of the above, an object of the present invention is to improve the characteristics of an ozone TEOS film formed on a capacitor.

  In order to achieve the above object, a semiconductor device manufacturing apparatus according to the present invention includes a chamber having a substrate holder for holding a semiconductor substrate, and an ozone TEOS supply means for supplying a mixture of gaseous TEOS and ozone gas into the chamber. And a primer supply means for supplying a gaseous primer having hydrophobicity into the chamber.

  According to the apparatus for manufacturing a semiconductor device according to the present invention, since the chamber is provided with the primer agent supply means for supplying the gaseous primer agent having hydrophobicity, the protective film formed under the ozone TEOS film or Since a hydrophobic primer layer can be formed on the surface of a base film such as a base oxide film, an ozone TEOS film having excellent step coverage can be grown.

  In the semiconductor device manufacturing apparatus according to the present invention, the primer is preferably hexamethyldisilazane.

  By doing so, the surface of the base film such as the protective film or the base oxide film can be reliably made hydrophobic.

  The apparatus for manufacturing a semiconductor device according to the present invention preferably further includes means for mixing the mixture supplied from the ozone TEOS supply means and the primer supplied from the primer supply means and supplying the mixture into the chamber. .

  With this configuration, after forming a hydrophobic primer layer on the surface of a base film such as a protective film or a base oxide film, an ozone TEOS film can be grown on the primer layer, so that excellent step coverage can be obtained. The ozone TEOS film can be formed with good mass productivity.

  In the semiconductor device manufacturing apparatus according to the present invention, it is preferable that the ozone TEOS supply means has a means for converting gaseous TEOS into mist and then mixing it with ozone gas.

  In this manner, the ozone TEOS film can be grown even if the ozone concentration in the ozone TEOS method is low, so that the ozone TEOS film has good film quality without defects such as voids and has a large amount of moisture in the film. A film can be formed.

  In the semiconductor device manufacturing apparatus according to the present invention, it is preferable that the ozone TEOS supply means has a means for charging a mist made of gaseous TEOS.

  By doing so, the mist composed of TEOS can be charged, so that the growth rate of the ozone TEOS film can be improved and the thickness of the ozone TEOS film can be increased.

  In this case, it is preferable that the substrate holder has means for giving the semiconductor substrate a polarity opposite to the polarity with which the mist is charged.

  This makes it possible to electrostatically adsorb the charged TEOS mist on the surface of the semiconductor substrate, so that the growth rate and the film thickness of the ozone TEOS film can be further increased.

  According to the semiconductor device manufacturing apparatus of the present invention, since the hydrophobic primer layer can be formed on the surface of the base film such as the protective film or the base oxide film formed below the ozone TEOS film, the step coverage can be improved. An excellent ozone TEOS film can be grown.

(1st Embodiment)
Hereinafter, a semiconductor device according to the first embodiment and a method for manufacturing the same will be described with reference to FIGS. 1 (a) to 1 (c) and FIGS. 2 (a) and 2 (b).

  First, as shown in FIG. 1A, after an element isolation region 101 and a gate electrode 102 of an FET are formed on a semiconductor substrate 100, an impurity diffusion layer of an FET (not shown) is formed on the surface of the semiconductor substrate 100. After that, an insulating film 103 is deposited over the entire surface of the element isolation region 101 and the gate electrode 102.

  Next, a capacitor lower electrode 104, a capacitor insulating film 105 made of a high dielectric film or a high dielectric film, and a capacitor upper electrode 106 are formed on the insulating film 103 and above the element isolation region 102. Note that a capacitive element is constituted by the capacitive lower electrode 104, the capacitive insulating film 105, and the capacitive upper electrode 106.

  As the capacitor lower electrode 104 and the capacitor upper electrode 106, a single-layer film made of platinum, iridium, palladium, ruthenium, or an alloy of two or more thereof, or two kinds of a platinum film, an iridium film, a palladium film, and a ruthenium film After depositing a metal film composed of a laminated film composed of the above films by a sputtering method, it can be formed by patterning the metal film.

  Further, as the capacitor insulating film 105, a high dielectric film or a ferroelectric film containing strontium, bismuth, tantalum, or the like as a main component can be used.

  Next, as shown in FIG. 1B, a first protective film 107 made of a silicon oxide film is deposited by an ozone TEOS method so as to cover the capacitor. As the first protective film 107, a silicon oxide film containing no impurity, a silicon oxide film containing boron and phosphorus, a silicon oxide film containing phosphorus, a silicon oxide film containing boron, or the like can be used. Accordingly, when the first protective film 107 is formed, the flatness of the first protective film 107 is improved, and the stabilization and long life of the capacitor can be realized.

  Next, after forming a contact hole 108 of the FET in the insulating film 103 and forming a contact hole 109 of the capacitor in the first protective film 107, the contact hole 108 is formed over the entire surface of the insulating film 103 and the first protective film 107. Then, a metal film including a stacked film of a titanium film, a titanium nitride film, an aluminum film, and a titanium nitride film is deposited. Next, a first wiring layer 110 connected to the impurity diffusion layer of the FET or the capacitor upper electrode 106 is formed by patterning the metal film, and then the first wiring layer 110 is formed under a nitrogen atmosphere. The first heat treatment is performed at a temperature of 400 ° C. for 30 minutes to reduce the density and stress of the first wiring layer 110.

  Next, as shown in FIG. 1C, a silicon oxide film containing no impurities, boron, and the like are entirely formed on the first wiring layer 110 and the first protective film 107 by the normal pressure CVD method. After depositing a base oxide film 111 made of a silicon oxide film containing phosphorus, a silicon oxide film containing phosphorus or a silicon oxide film containing boron and having a thickness of, for example, 100 nm, a first ozone TEOS having a relatively low ozone concentration. A first ozone TEOS film 112 having a thickness of, for example, 150 nm and having a relatively large amount of water in the film is grown on the base oxide film 111 by a method, and then a second ozone concentration is relatively high. By the ozone TEOS method, a second ozone TEOS film 113 having a thickness of, for example, 0.3 μm to 1.7 μm and having a relatively small amount of moisture in the film is grown on the first ozone TEOS film 112. You.

  As described above, an interlayer insulating film is formed by the base oxide film 111, the first ozone TEOS film 112, and the second ozone TEOS film 113. The thickness of the interlayer insulating film is about 1 μm or more above the first wiring layer 110 on the capacitor upper electrode 106 in consideration of flattening by reflow, and the first protection layer on the capacitor insulating film 105 is formed. The thickness is about 2 μm or more above the film 107.

  Next, a second heat treatment is performed at a temperature of 450 ° C. in an oxygen atmosphere for 30 minutes to 1 hour to reinforce the stress of the first and second ozone TEOS films 112 and 113 and to perform the first and second heat treatment. The oxygen in the ozone TEOS films 112 and 113 is supplied to the capacitance insulating film 105.

  By the way, in the first ozone TEOS method, it is preferable to use a mist made of gaseous TEOS and having a particle size equal to or smaller than a predetermined size. By doing so, the film quality of the first ozone TEOS film 112 can be improved. Further, it is preferable that the first ozone TEOS method be performed using a mist of TEOS charged with positive or negative static electricity. By doing so, the growth rate of the first ozone TEOS film 112 is improved and the dependence on the base is eliminated, so that the thickness of the first ozone TEOS film 113 can be increased. In this case, when the semiconductor substrate 100 is charged with static electricity having a polarity opposite to that of the mist made of TEOS, the growth rate of the first TEOS film 112 can be further improved.

  A method for forming a mist made of gaseous TEOS, a method for reducing the particle size of the mist to a predetermined value or less, a method for charging the mist with static electricity, and a method for charging the semiconductor substrate 100 with static electricity are described in the third embodiment. Will be described.

  Further, it is preferable that the second ozone TEOS method be performed in a temperature range of 350 to 450 ° C. to grow the second ozone TEOS film 113. By doing so, the second heat treatment can be performed at a temperature of 450 ° C., so that the stress of the second ozone TEOS film 113 can be increased and the film quality of the second ozone TEOS film 113 can be made dense.

  Next, as shown in FIG. 2A, after a contact hole 114 is formed in an interlayer insulating film including a base oxide film 111, a first ozone TEOS film 112, and a second ozone TEOS film 113, On the ozone TEOS film 113, a second wiring layer 115 including a stacked film of a titanium film, a titanium nitride film, an aluminum film, and a titanium nitride film is formed. After that, a third heat treatment is performed for 30 minutes at a temperature of 400 ° C. in a nitrogen atmosphere, so that the second wiring layer 115 is densified and reduced in stress.

  Next, as shown in FIG. 2B, a second protective film 116 made of a silicon nitride film is formed on the second ozone TEOS film 113 so as to cover the second wiring layer 115 by a plasma CVD method. After the deposition, the semiconductor device according to the first embodiment is obtained.

  According to the first embodiment, over the entire surface of the first wiring layer 110 and the first protective film 107, the base oxide film 111 having no base dependency and having excellent compatibility with the ozone TEOS film is formed. After the deposition, the first ozone TEOS film 112 is grown on the base oxide film 111. Therefore, the first ozone TEOS film 112 is made of a material for the first wiring layer 110 and the first protective film 107. It grows well without being affected differently, that is, without being affected by the dependence on the base. For this reason, the thickness of the first ozone TEOS film 112 becomes uniform, so that the thickness of the interlayer insulating film also becomes uniform, so that a capacitor having excellent stability and long life can be obtained.

  Since the first ozone TEOS film 112 is formed by the first ozone TEOS method performed under a relatively low ozone concentration, the first ozone TEOS film 112 grows without causing defects such as vacancies and the like. Moisture is relatively high. Since the moisture in the first ozone TEOS film 112 is relatively large, the adhesion to the base oxide film 111 is improved.

  Further, since the second ozone TEOS film 113 is formed by the second ozone TEOS method performed under a relatively high ozone concentration, moisture in the film is relatively small. For this reason, the second ozone TEOS film 113 gives a large amount of stress to the capacitor insulating film 105 of the capacitor, and the capacitor insulating film 105 is favorably spontaneously polarized.

By the way, in order to favorably generate spontaneous polarization in the capacitor insulating film 105 of the capacitor, the stress of the second ozone TEOS film 113 after the second heat treatment should be 1 × 10 ⁴ N / cm ² or less. The tensile stress (tensile stress) of × 10 ² N / cm ² or more is preferable. By doing so, the spontaneous polarization characteristics of the capacitor insulating film 105 are improved, so that the characteristics of the capacitor are improved.

  The thickness of the second ozone TEOS film 113 is preferably in the range of 0.3 μm to 1.7 μm. If the thickness of the second ozone TEOS film 113 exceeds 1.7 μm, cracks may be generated by the second heat treatment, and if the thickness of the second ozone TEOS film 113 is less than 0.3 μm. In addition, since the required flatness of the interlayer insulating film cannot be obtained, the formation of the second wiring layer 115 by patterning may cause etching residue or the like.

The concentration of ozone in the first ozone TEOS method (in this specification, the concentration of oxygen gas including ozone gas is referred to as the concentration of ozone for convenience) may be 25 g / m ³ or less, and may be 20 g / m ³ or less. More preferably, it is not more than m ³ . When the concentration of ozone is 25 g / m ³ or less, the first ozone TEOS film 112 does not have a defect such as a defect due to the self-reflow property of the first ozone TEOS film 112. Note that the lower limit of the ozone concentration may be in a range where the first ozone TEOS film 112 grows.

In order to set the ozone concentration in the first ozone TEOS method to 25 g / m ³ or less, the value of (ozone flow rate / TEOS flow rate) may be set to 3 or less.

The ozone concentration in the second ozone TEOS method may be 130 g / m ³ or more, and more preferably 150 g / m ³ or more. When the ozone concentration is 130 g / m ³ or more, sufficient stress can be applied to the capacitor insulating film 105, and cracks occur in the second ozone film 113 during the second heat treatment due to the low moisture content. Can be prevented. Note that the upper limit of the ozone concentration may be within a range in which the second ozone TEOS film 113 grows.

In order to set the ozone concentration in the second ozone TEOS method to 130 g / m ³ or more, the value of (ozone flow rate / TEOS flow rate) may be set to 15 or more.

FIG. 3 shows the results of experiments performed to evaluate the first embodiment. The first conventional example (in the case where an interlayer insulating film made of a plasma TEOS film is used) and the second conventional example (single unit) In the case of using an interlayer insulating film composed of a layer of an ozone TEOS film) and in the first embodiment (in the case of using an interlayer insulating film composed of a base oxide film, a first ozone TEOS film and a second ozone TEOS film). It shows the amount of remanent polarization of the capacitive insulating film. Residual polarization amount is in the first conventional example is 3 .mu.C / cm ^2, in the second conventional example was 10 [mu] C / cm ^2, in the first embodiment a 17mμC / cm ^2, a first embodiment According to the results, it was confirmed that the amount of remanent polarization of the capacitive insulating film was greatly increased.

  FIGS. 4A and 4B show the relationship between the magnitude of the interlayer leakage current between the first wiring layer and the second wiring layer and the frequency of occurrence, and FIG. FIG. 4B shows the case of the first embodiment. The frequency of conforming products having an interlayer leakage current value of 0.01 nA is about 75% in the second conventional example, but about 90% in the first embodiment. It can be seen that the frequency of non-defective products is greatly improved.

  In the first embodiment, the first and third heat treatments are performed at 400 ° C., but may be performed at 350 ° C. to 450 ° C.

  In the first embodiment, the second heat treatment was performed at a temperature of 450 ° C. in an oxygen atmosphere. However, the oxygen atmosphere may be oxygen gas alone or oxygen gas and another gas. May be used. Further, the temperature of the second heat treatment may be in the range of 350 ° C to 450 ° C.

  In the first embodiment, as the first wiring layer 110 and the second wiring layer 115, a stacked film of a titanium film, a titanium nitride film, an aluminum film, and a titanium nitride film is used. A stacked film of a titanium film and an aluminum film, a stacked film of a titanium film, an aluminum film, and a titanium tungsten film can be used.

  In the first embodiment, the interlayer insulating film is constituted by the base oxide film 111, the first ozone TEOS film 112, and the second ozone TEOS film 113. Instead, the interlayer insulating film is formed by the base oxide film. The first ozone TEOS film 112 and the second ozone TEOS film 113 may be formed without forming the first ozone TEOS film 112, or the base oxide film 111 and the second ozone TEOS film 112 may be formed without forming the first ozone TEOS film 112. Alternatively, the second ozone TEOS film 113 may be used.

(Modification of First Embodiment)
Hereinafter, a semiconductor device according to a modification of the first embodiment and a method for manufacturing the same will be described with reference to FIGS.

  First, similarly to the first embodiment, after forming the element isolation region 101 and the gate electrode 102 of the FET on the semiconductor substrate 100, the insulating film 103 is formed over the entire surface of the element isolation region 101 and the gate electrode 102. After that, a capacitor composed of a capacitor lower electrode 104, a capacitor insulating film 105 made of a high dielectric film or a high dielectric film, and a capacitor upper electrode 106 is formed above the element isolation region 102 on the insulating film 103. (See FIG. 1A).

  Next, as in the first embodiment, after depositing a first protective film 107 made of a silicon oxide film so as to cover the capacitive element by the ozone TEOS method, a contact hole 108 of the FET is formed in the insulating film 103. At the same time, a contact hole 109 of the capacitor is formed in the first protective film 107, and then a first wiring layer 110 connected to the impurity diffusion layer of the FET or the capacitor upper electrode 106 is formed (see FIG. 1B). ). Next, as shown in FIG. 5A, a silicon oxide film containing no impurities, boron, and the like are entirely formed on the first wiring layer 110 and the first protective film 107 by the normal pressure CVD method. After depositing a base oxide film 111 made of a silicon oxide film containing phosphorus, a silicon oxide film containing phosphorus or a silicon oxide film containing boron and having a thickness of, for example, 100 nm, a first ozone TEOS having a relatively low ozone concentration. By a method, a first ozone TEOS film 112 having a thickness of, for example, 150 nm and having a relatively large amount of moisture in the film is grown on the base oxide film 111.

  After that, a first plasma treatment is performed on the first ozone TEOS film 112 to form a first surface treatment layer 112a on the surface of the first ozone TEOS film 112.

As the first plasma treatment, plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas, N ₂ O gas, O ₂ gas, Ar gas, Cl ₂ gas, and C ₂ F ₆ gas is used. Preferably, plasma coating or plasma sputter etching is performed.

  In this manner, the first ozone TEOS film 112 has a first surface treatment layer 112a formed of a hardened layer having a thickness of about several nm on the surface of the first ozone TEOS film 112. The ability to inhibit the diffusion of moisture is improved.

Further, it is preferable that the first plasma treatment is a nitridation treatment using plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas and N ₂ O gas.

  By doing so, the first surface treatment layer 112a made of a silicon nitride layer having a high moisture diffusion inhibiting ability is formed on the surface of the first ozone TEOS film 112, so that the capacitance of the first ozone TEOS film 112 is reduced. Diffusion of moisture into the insulating film 105 or diffusion of moisture in the atmosphere into the first ozone TEOS film 112 can be prevented.

  Next, by a second ozone TEOS method having a relatively high ozone concentration, a thickness of, for example, 0.3 μm to 1.7 μm is formed on the first ozone TEOS film 112 on which the first surface treatment layer 112 a is formed. A second ozone TEOS film 113 having a thickness and having relatively little moisture in the film is grown.

  After that, a second plasma treatment is performed on the second ozone TEOS film 113 to form a second surface treatment layer 113a on the surface of the second ozone TEOS film 113.

As the second plasma treatment, plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas, N ₂ O gas, O ₂ gas, Ar gas, Cl ₂ gas, and C ₂ F ₆ gas is used. Preferably, plasma coating or plasma sputter etching is performed.

  In this case, the second ozone TEOS film 113 has a second surface treatment layer 113a formed of a hardened layer having a thickness of about several nm on the surface of the second ozone TEOS film 113. The ability to inhibit the diffusion of moisture is improved.

Further, it is preferable that the second plasma treatment is a nitridation treatment using plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas and N ₂ O gas.

  In this way, the second surface treatment layer 113a made of a silicon nitride layer having a high moisture diffusion inhibiting ability is formed on the surface of the second ozone TEOS film 113. Diffusion of moisture into the insulating film 105 or diffusion of moisture in the air into the second ozone TEOS film 113 can be prevented.

  Next, as shown in FIG. 5B, as in the first embodiment, contact holes 114 are formed in the interlayer insulating film including the base oxide film 111, the first ozone TEOS film 112, and the second ozone TEOS film 113. Is formed, a second wiring layer 115 is formed on the second ozone TEOS film 113.

  Next, as shown in FIG. 5C, similarly to the first embodiment, the second protection layer is formed on the second ozone TEOS film 113 so as to cover the second wiring layer 115 by the plasma CVD method. When the film 116 is deposited, a semiconductor device according to a modification of the first embodiment is obtained.

  In the modification of the first embodiment, the second plasma processing is performed on the second ozone TEOS film 113 immediately after the second ozone TEOS film 113 is grown, and the second plasma processing is performed. The second surface treatment layer 113a is formed on the surface of the ozone TEOS film 113. Instead, the contact hole 114 is formed in the second ozone TEOS film 113 after the second ozone TEOS film 113 is planarized. After that, or after forming the second wiring layer 115 on the second ozone TEOS film 113, a second plasma treatment may be performed to form the second surface treatment layer 113a.

(Second embodiment)
Hereinafter, a semiconductor device and a method of manufacturing the same according to the second embodiment will be described with reference to FIGS. 6A to 6C and FIGS. 7A and 7B.

  First, as shown in FIG. 6A, after an element isolation region 201 and a gate electrode 202 of an FET are formed on a semiconductor substrate 200, an impurity diffusion layer of the FET (not shown) is formed on the surface of the semiconductor substrate 200. After that, an insulating film 203 is deposited over the entire surface of the element isolation region 201 and the gate electrode 202.

  Next, a capacitor lower electrode 204, a capacitor insulating film 205 made of a high dielectric film or a high dielectric film, and a capacitor upper electrode 206 are formed on the insulating film 203 and above the element isolation region 202. Note that a capacitive element is constituted by the capacitive lower electrode 204, the capacitive insulating film 205, and the capacitive upper electrode 206.

  As the capacitor lower electrode 204 and the capacitor upper electrode 206, a single-layer film made of platinum, iridium, palladium, ruthenium, or an alloy of two or more of these, or two kinds of a platinum film, an iridium film, a palladium film, and a ruthenium film After depositing a metal film composed of a laminated film composed of the above films by a sputtering method, it can be formed by patterning the metal film.

  Further, as the capacitor insulating film 205, a high dielectric film or a ferroelectric film containing strontium, bismuth, tantalum, or the like as a main component can be used.

  Next, as shown in FIG. 6B, a first protective film 207 made of a silicon oxide film is deposited by an ozone TEOS method so as to cover the capacitor. As the first protective film 207, a silicon oxide film containing no impurity, a silicon oxide film containing boron and phosphorus, a silicon oxide film containing phosphorus, a silicon oxide film containing boron, or the like can be used. Accordingly, when the first protective film 207 is formed, the flatness of the first protective film 207 can be improved, and the stability and long life of the capacitor can be realized.

  Next, after forming the contact hole 208 of the FET in the insulating film 203 and forming the contact hole 209 of the capacitor in the first protective film 207, the entire surface is formed on the insulating film 203 and the first protective film 207. Then, a metal film including a stacked film of a titanium film, a titanium nitride film, an aluminum film, and a titanium nitride film is deposited. Next, a first wiring layer 210 connected to the impurity diffusion layer of the FET or the capacitor upper electrode 206 is formed by patterning the metal film, and then the first wiring layer 210 is formed under a nitrogen atmosphere. The first heat treatment is performed at a temperature of 400 ° C. for 30 minutes to reduce the density and stress of the second wiring layer 210.

  Next, as shown in FIG. 6C, a silicon oxide film containing no impurities, boron, and the like are entirely formed on the first wiring layer 210 and the first protective film 207 by the normal pressure CVD method. After depositing a base oxide film 211 made of a silicon oxide film containing phosphorus, a silicon oxide film containing phosphorus or a silicon oxide film containing boron and having a thickness of, for example, 100 nm, 2 to 5 nm is formed on the base oxide film 211. To form a hydrophobic primer layer 212 having a thickness of Note that the primer layer 212 can be formed by supplying a gaseous primer agent made of, for example, HMDS (hexamethyldisilazane) to the surface of the semiconductor substrate 200.

  Next, a first ozone TEOS film 213 having a thickness of, for example, 150 nm and having a relatively large amount of water in the film is grown on the primer layer 212 by a first ozone TEOS method having a relatively low ozone concentration. After that, the second ozone TEOS method having a relatively high ozone concentration has a thickness of, for example, 0.3 μm to 1.7 μm on the first ozone TEOS film 213 and the moisture in the film is relatively low. A small amount of the second ozone TEOS film 214 is grown.

  As described above, an interlayer insulating film is formed by the base oxide film 211, the primer layer 212, the first ozone TEOS film 213, and the second ozone TEOS film 214. The thickness of the interlayer insulating film is about 1 μm or more above the first wiring layer 210 on the capacitor upper electrode 206 in consideration of flattening by reflow, and the first protection film on the capacitor insulating film 205 is formed. The thickness is set to be about 2 μm or more above the film 207.

  Next, a second heat treatment is performed for 1 hour at a temperature of 450 ° C. in an oxygen atmosphere to reinforce the stress of the first and second ozone TEOS films 213 and 214 and to perform the first and second ozone TEOS. The oxygen in the films 213 and 214 is supplied to the capacitor insulating film 205.

  Next, as shown in FIG. 7A, after a contact hole 215 is formed in an interlayer insulating film including a base oxide film 211, a primer layer 212, a first ozone TEOS film 213, and a second ozone TEOS film 214. On the second ozone TEOS film 214, a second wiring layer 216 made of a laminated film of a titanium film, a titanium nitride film, an aluminum film, and a titanium nitride film is formed. After that, a third heat treatment is performed at a temperature of 400 ° C. in a nitrogen atmosphere for 30 minutes, so that the second wiring layer 216 is densified and reduced in stress.

  Next, as shown in FIG. 7B, a second protective film 217 made of a silicon nitride film is formed on the second ozone TEOS film 214 so as to cover the second wiring layer 216 by a plasma CVD method. After the deposition, the semiconductor device according to the second embodiment is obtained.

  According to the second embodiment, between the first wiring layer 210 and the first protective film 207 and the first ozone TEOS film 213, there is no dependence on the underlayer and the first ozone TEOS film 213 Since the base oxide film 211 having excellent conformability is interposed, the first ozone TEOS film 213 is not affected by different materials of the first wiring layer 210 and the first protective film 207, that is, Since it grows well without being affected by the underlayer dependence, it is formed with a uniform thickness.

  Further, after forming the hydrophobic primer layer 212 on the base oxide film 211, and then growing the first ozone TEOS film 213 on the primer layer 212, the first ozone TEOS film 213 is more excellent. To grow. That is, since the ozone TEOS film has a property that it grows well on the surface of the hydrophobic film, the surface of the base oxide film 211 is formed by the hydrophobic primer layer 212 as in the second embodiment. When the first ozone TEOS film 213 is grown after being made hydrophobic, the first ozone TEOS film 213 having excellent step coverage and the interlayer insulating film having excellent step coverage can be formed.

  Further, since the first ozone TEOS film 213 is formed by the first ozone TEOS method in which the ozone concentration is relatively low, the first ozone TEOS film 213 is formed without causing defects such as voids and the moisture in the film is reduced. Relatively high. Since the first ozone TEOS film 213 has a relatively large amount of moisture in the film, the adhesion to the base oxide film 211 is improved.

  Further, since the second ozone TEOS film 214 is formed by the second ozone TEOS method in which the ozone concentration is relatively high, moisture in the film is relatively small. For this reason, the second ozone TEOS film 214 gives a large amount of stress to the capacitor insulating film 205 of the capacitor, and the capacitor insulating film 205 is favorably spontaneously polarized.

  FIGS. 8A and 8B show the relationship between the magnitude of the interlayer leakage current between the first wiring layer and the second wiring layer and the frequency of occurrence, and FIG. FIG. 8B shows the case of the second embodiment. The frequency of non-defective products having an interlayer leakage current value of 0.01 nA is about 90% in the first embodiment, whereas it is 100% in the second embodiment. It can be seen that the frequency of non-defective products is greatly improved as compared with the first embodiment.

  Note that the thickness of the second ozone TEOS film 214 is preferably in the range of 0.3 μm to 1.7 μm, as in the first embodiment.

Further, similarly to the first embodiment, the concentration of ozone in the first ozone TEOS method may be 25 g / m ³ or less, more preferably 20 g / m ³ or less, and the second ozone TEOS method. May be 130 g / m ³ or more, and more preferably 150 g / m ³ or more.

  In the second embodiment, the interlayer insulating film is constituted by the base oxide film 211, the primer layer 212, the first ozone TEOS film 213, and the second ozone TEOS film 214. The oxide film 211 may be formed without using the primer layer 212, the first ozone TEOS film 213, and the second ozone TEOS film 214, or without forming the first ozone TEOS film 213. , A base oxide film 211, a primer layer 212, and a second ozone TEOS film 214.

(Modification of the second embodiment)
Hereinafter, a semiconductor device according to a modification of the second embodiment and a method of manufacturing the same will be described with reference to FIGS.

  First, similarly to the first embodiment, after forming the element isolation region 201 and the gate electrode 202 of the FET on the semiconductor substrate 200, the insulating film 203 is formed over the entire surface of the element isolation region 201 and the gate electrode 202. After that, a capacitor composed of a capacitor lower electrode 204, a capacitor insulating film 205 made of a high dielectric film or a high dielectric film, and a capacitor upper electrode 206 is formed above the element isolation region 202 on the insulating film 203. (See FIG. 6A).

  Next, as in the first embodiment, after depositing a first protective film 207 made of a silicon oxide film so as to cover the capacitive element by the ozone TEOS method, a contact hole 208 of the FET is formed in the insulating film 203. At the same time, a contact hole 209 of the capacitor is formed in the first protective film 207, and then a first wiring layer 210 connected to the impurity diffusion layer of the FET or the capacitor upper electrode 206 is formed (see FIG. 6B). ).

  Next, as shown in FIG. 9A, a silicon oxide film containing no impurities, boron, and the like are entirely formed on the first wiring layer 210 and the first protective film 207 by the normal pressure CVD method. After depositing a base oxide film 211 made of a silicon oxide film containing phosphorus, a silicon oxide film containing phosphorus or a silicon oxide film containing boron and having a thickness of, for example, 100 nm, 2 to 5 nm is formed on the base oxide film 211. To form a hydrophobic primer layer 212 having a thickness of

  Next, a first ozone TEOS film 213 having a thickness of, for example, 150 nm and having a relatively large amount of water in the film is grown on the primer layer 212 by a first ozone TEOS method having a relatively low ozone concentration. Let it.

  After that, a first plasma treatment is performed on the first ozone TEOS film 213 to form a first surface treatment layer 213a on the surface of the first ozone TEOS film 213.

As the first plasma treatment, plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas, N ₂ O gas, O ₂ gas, Ar gas, Cl ₂ gas, and C ₂ F ₆ gas is used. Preferably, plasma coating or plasma sputter etching is performed.

  By doing so, the first ozone TEOS film 213 has a first surface treatment layer 213a formed of a hardened layer having a thickness of about several nm on the surface of the first ozone TEOS film 213. The ability to inhibit the diffusion of moisture is improved.

Further, it is preferable that the first plasma treatment is a nitridation treatment using plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas and N ₂ O gas.

  By doing so, the first surface treatment layer 213a made of a silicon nitride layer having a high moisture diffusion inhibiting ability is formed on the surface of the first ozone TEOS film 213. Diffusion of moisture into the insulating film 205 or diffusion of moisture in the air into the first ozone TEOS film 213 can be prevented.

  Next, by a second ozone TEOS method having a relatively high ozone concentration, a thickness of, for example, 0.3 μm to 1.7 μm is formed on the first ozone TEOS film 213 on which the first surface treatment layer 213a is formed. A second ozone TEOS film 214 having a thickness and having relatively little moisture in the film is grown.

  After that, a second plasma treatment is performed on the second ozone TEOS film 214 to form a second surface treatment layer 214a on the surface of the second ozone TEOS film 214.

As the second plasma treatment, plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas, N ₂ O gas, O ₂ gas, Ar gas, Cl ₂ gas, and C ₂ F ₆ gas is used. Preferably, plasma coating or plasma sputter etching is performed.

  In this manner, the second ozone TEOS film 214 has a second surface treatment layer 214a formed of a hardened layer having a thickness of about several nm on the surface of the second ozone TEOS film 214. The ability to inhibit the diffusion of moisture is improved.

Further, it is preferable that the second plasma treatment is a nitridation treatment using plasma composed of a gas containing at least one of N ₂ gas, NH ₃ gas and N ₂ O gas.

  In this way, the second ozone TEOS film 214 is formed with the second surface treatment layer 214a made of a silicon nitride layer having a high moisture diffusion preventing ability on the surface of the second ozone TEOS film 214. Diffusion of moisture into the insulating film 205 or diffusion of moisture in the air into the second ozone TEOS film 214 can be prevented.

  Next, as shown in FIG. 9B, after a contact hole 215 is formed in an interlayer insulating film including a base oxide film 211, a primer layer 212, a first ozone TEOS film 213, and a second ozone TEOS film 214. Then, a second wiring layer 216 is formed on the second ozone TEOS film 214.

  Next, as shown in FIG. 9C, similarly to the second embodiment, the second protection layer is formed on the second ozone TEOS film 214 so as to cover the second wiring layer 216 by the plasma CVD method. When the film 217 is deposited, a semiconductor device according to a modification of the second embodiment is obtained.

  In the modification of the second embodiment, the second plasma processing is performed on the second ozone TEOS film 214 immediately after the second ozone TEOS film 214 is grown, and the second plasma processing is performed. The second surface treatment layer 214a is formed on the surface of the ozone TEOS film 214. Instead, the contact hole 215 is formed in the second ozone TEOS film 214 after the second ozone TEOS film 214 is planarized. After the formation, or after forming the second wiring layer 216 on the second ozone TEOS film 214, a second plasma treatment may be performed to form the second surface treatment layer 214a.

(Third embodiment)
Hereinafter, as a third embodiment, a manufacturing apparatus for manufacturing the semiconductor device according to the first or second embodiment will be described with reference to FIG.

  FIG. 10 shows a schematic overall configuration of a semiconductor device manufacturing apparatus. As shown in FIG. 10, a substrate holder 302 for holding a semiconductor substrate 301 is provided in an upper portion inside a chamber 300. A heater 303 for heating the semiconductor substrate 301 and a suction plate 304 for electrostatically sucking the semiconductor substrate 301 are provided below the substrate holder 302. A voltage power supply 305 is connected to the attraction plate 304, and by applying a voltage to the attraction plate 304 from the voltage power supply 305, the semiconductor substrate 301 can be electrostatically attracted and the semiconductor substrate 301 is charged with positive or negative static electricity. Can be done.

  A TEOS warmer 310 is provided outside the chamber 300, and a TEOS storage tank 311 for storing a TEOS liquid is housed inside the TEOS warmer 310. A nitrogen gas supply pipe 312 extends inside the TEOS storage tank 311, and the TEOS liquid is bubbled by the nitrogen gas supplied from the nitrogen gas supply pipe 312. One end of a TEOS supply pipe 314 having a flow control valve 313 extends above the TEOS storage tank 311, and TEOS gasified by bubbling is adjusted in flow rate and the other end of the TEOS supply pipe 314 is provided. Sent to the side. A mist generating charger 315 and a mist particle size filter 316 are provided in the middle of the TEOS supply pipe 314.

  The mist generation charger 315 converts the gaseous TEOS into mist and charges the mist with positive or negative static electricity. Examples of the method of converting gaseous TEOS into a mist include a method using an ultrasonic vibrator, a method using a pressure difference, and a method using a Venturi atomizer.As a method for charging the mist with static electricity, There is a method in which electrons emitted by gas discharge such as corona discharge are attached to a mist to charge negative static electricity.

  Further, the mist particle size filter 316 allows only mist having a particle size equal to or smaller than a predetermined particle size, for example, a mist having a particle size of 0.01 μm to several μm among the mist made of TEOS. As the mist particle size filter 316, a first method of mechanically removing the material such as a mesh, for example, a method in which a transport pipe for transporting the mist is provided in a zigzag shape, and a speed utilizing the mist, specifically, A second method of removing a mist having a large particle diameter by utilizing the principle that the larger the particle diameter of the mist is, the larger the kinetic energy is, so that the mist tends to collide with the wall surface of the curved portion of the transport pipe; In particular, an electric field is applied to the transport pipe that transports the mist, and the principle that the larger the particle size of the mist is, the larger the electric energy is, so that it easily collides with the wall of the transport pipe. And a third method for removing mist having a large particle size.

  An ozonizer 320 for generating ozone is provided outside the chamber 300. Oxygen gas supplied from the oxygen gas supply pipe 321 is supplied to the oxygen gas containing ozone gas by the ozonizer 320. Is simply referred to as ozone.) One end of an ozone supply pipe 323 having a flow rate adjustment valve 322 extends inside the ozonizer 320, and the generated ozone is adjusted in flow rate and sent to the other end side of the ozone supply pipe 323.

  The other end of the TEOS supply pipe 314 and the other end of the ozone supply pipe 323 are merged and connected to one end of the ozone TEOS supply pipe 330. TEOS sent from the TEOS supply pipe 314 and ozone sent from the ozone supply pipe 323 Are mixed and sent to the other end of the ozone TEOS supply pipe 330.

  An HMDS warmer 340 is provided outside the chamber 300, and an HMDS storage tank 341 for storing the HMDS liquid is housed inside the HMDS warmer 340. A nitrogen gas supply pipe 342 extends inside the HMDS storage tank 341, and the HMDS liquid is bubbled by the nitrogen gas supplied from the nitrogen gas supply pipe 342. One end of an HMDS supply pipe 344 having a flow rate control valve 343 extends above the HMDS storage tank 341. The HMDS gasified by bubbling is adjusted in flow rate and the other end of the HMDS supply pipe 344 is provided. Sent to the side.

  The other end of the ozone TEOS supply pipe 330 and the other end of the HMDS supply pipe 344 are connected to one end of a raw material supply pipe 351 via a three-way valve 350 that mixes ozone TEOS and HMDS. After being supplied to the inside of the chamber 300 from the raw material supply pipe 351 alone or mixed, it is supplied from the raw material supply part 352 to the surface of the semiconductor substrate 301.

  According to the semiconductor device manufacturing apparatus according to the present invention, an ozone TEOS film having excellent step coverage can be grown.

3A to 3C are cross-sectional views illustrating respective steps of a method for manufacturing a semiconductor device according to the first embodiment. FIGS. 3A and 3B are cross-sectional views illustrating respective steps of a method for manufacturing a semiconductor device according to the first embodiment. FIGS. FIG. 9 is a diagram showing the results of experiments performed to evaluate the first embodiment, and showing the amount of remanent polarization of the capacitance insulating film in the first conventional example, the second conventional example, and the first embodiment. (A) is a diagram showing the frequency at which no interlayer leakage current occurs in the second conventional example, and (b) is a diagram showing the frequency at which no interlayer leakage current occurs in the first embodiment. (A)-(c) is sectional drawing which shows each process of the manufacturing method of the semiconductor device which concerns on the modification of 1st Embodiment. (A)-(c) is sectional drawing which shows each process of the manufacturing method of the semiconductor device which concerns on 2nd Embodiment. FIGS. 7A and 7B are cross-sectional views illustrating respective steps of a method for manufacturing a semiconductor device according to a second embodiment. (A) is a diagram showing a frequency at which no interlayer leak current occurs in the first embodiment, and (b) is a diagram showing a frequency at which no interlayer leak current occurs in the second embodiment. (A)-(c) is sectional drawing which shows each process of the manufacturing method of the semiconductor device which concerns on the modification of 2nd Embodiment. 1 is a schematic overall configuration diagram showing a semiconductor device manufacturing apparatus according to the present invention. (A)-(c) is sectional drawing which shows each process of the manufacturing method of the semiconductor device which concerns on a prior art example. (A) And (b) is sectional drawing which shows each process of the manufacturing method of the semiconductor device which concerns on a prior art example.

Explanation of reference numerals

REFERENCE SIGNS LIST 100 semiconductor substrate 101 element isolation region 102 gate electrode 103 insulating film 104 capacitor lower electrode 105 capacitor insulating film 106 capacitor upper electrode 107 first protective film 108 contact hole 109 contact hole 110 first wiring layer 111 base oxide film 112 first Ozone TEOS film 112a first surface treatment layer 113 second ozone TEOS film 113a second surface treatment layer 114 contact hole 115 second wiring layer 116 second protective film 200 semiconductor substrate 201 element isolation region 202 gate electrode 203 Insulating film 204 Capacitance lower electrode 205 Capacitance insulating film 206 Capacitance upper electrode 207 First protective film 208 Contact hole 209 Contact hole 210 First wiring layer 211 Base oxide film 212 Primer layer 213 First ozone TEO Film 213a First surface treatment layer 214 Second ozone TEOS film 214a Second surface treatment layer 215 Contact hole 216 Second wiring layer 217 Second protective film 300 Chamber 301 Semiconductor substrate 302 Substrate holder 303 Heater 304 Suction plate 305 Voltage power supply 310 TEOS warmer 311 TEOS storage tank 312 Nitrogen gas supply pipe 313 Flow rate control valve 314 TEOS supply pipe 315 Mist generation charger 316 Mist particle size filter 320 Ozonizer 321 Oxygen gas supply pipe 322 Flow rate control valve 323 Ozone supply pipe 330 Ozone TEOS supply pipe 340 HMDS warmer 341 HMDS storage tank 342 Nitrogen gas supply pipe 343 Flow control valve 344 HMDS supply pipe 350 Three-way valve 351 Raw material supply pipe 352 Original Supply unit

Claims (6)

A chamber having a substrate holder for holding a semiconductor substrate,
Ozone TEOS supply means for supplying a mixture of gaseous TEOS and ozone gas into the chamber;
An apparatus for manufacturing a semiconductor device, comprising: a primer agent supply unit for supplying a gaseous primer agent having hydrophobicity in the chamber.   2. The apparatus according to claim 1, wherein the primer is hexamethyldisilazane.   2. The apparatus according to claim 1, further comprising a unit for mixing the mixture supplied from the ozone TEOS supply unit and the primer agent supplied from the primer agent supply unit and supplying the mixture into the chamber. An apparatus for manufacturing a semiconductor device according to the above.   2. The apparatus according to claim 1, wherein the ozone TEOS supply unit includes a unit configured to convert gaseous TEOS into mist and then mix the mist with the ozone gas. 3.   5. The semiconductor device manufacturing apparatus according to claim 4, wherein said ozone TEOS supply means has means for charging a mist made of gaseous TEOS.   6. The semiconductor device manufacturing apparatus according to claim 5, wherein the substrate holder has means for giving a polarity opposite to the polarity of the mist to the semiconductor substrate.

Images