JP2006140175A - Method for manufacturing semiconductor device and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a sidewall spacer without shaving a semiconductor substrate in a process for forming the LDD (Lightly-Doped Drain) of an MOS transistor. <P>SOLUTION: This method for manufacturing a semiconductor device comprises a step for forming a gate electrode 102 on a semiconductor substrate 100 through a gate insulating film 101, a step for depositing an organic/inorganic hybrid film 106 represented by SiC<SB>w</SB>H<SB>x</SB>O<SB>y</SB>N<SB>z</SB>(w>0, x≥0, y>0, z≥0) to cover the gate electrode 102, a step for transforming a predetermined portion of the organic/inorganic hybrid film 106 into an oxidation layer 108, a step for removing the oxidation layer 108 selectively so that a sidewall spacer 109 composed of the organic/inorganic hybrid film is formed on the sidewall of the gate electrode 102. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method of forming a sidewall spacer for forming an LDD without damaging the semiconductor substrate, particularly in the manufacturing process of a MOS transistor having a lightly-doped drain (LDD) structure, and the sidewall spacer to the semiconductor substrate. The present invention relates to a method for manufacturing a semiconductor device that can be removed without damaging the semiconductor device and a semiconductor device.

As miniaturization and speeding-up of element patterns in semiconductor devices progress, measures against hot carriers that degrade MOS transistor characteristics are becoming increasingly important. A typical countermeasure is a Lightly-Doped Drain (hereinafter referred to as LDD) structure. Hereinafter, an example of a conventional LDD forming process will be described with reference to FIGS. First, as shown in FIG. 16 (a), a gate electrode 3 made of, for example, a 200 nm polysilicon film is formed on a semiconductor substrate 1 through a 2 nm gate oxide film 2, for example, by a known photolithography technique and dry etching technique. It forms using. Next, a self-aligned manner by ion implantation with low N-type diffusion layers 4 and 5 impurity concentration serving as a part of the source and drain of the gate electrode 3 as a mask (e.g., a P ⁺ 5 × 10 ¹³ pieces / cm ²⁾ To form.

Next, as shown in FIG. 16B, a silicon oxide film 7 is deposited by CVD, for example, 150 nm so as to cover the surface of the substrate 6 to be processed. Next, as shown in FIG. 16C, anisotropic etching of the silicon oxide film 7 is performed to remove the silicon oxide film 7 so that only the side surfaces of the gate electrode 3 are left, and sidewall spacers 8 are formed. To do. Next, as shown in FIG. 16D, the gate electrode 3 and the side wall spacer 8 are used as a mask, and other sources and drains are formed by ion implantation (for example, As ⁺ 5 × 10 ¹⁵ / cm ² ). If the high-concentration diffusion layers 9 and 10 to be portions are formed in a self-aligned manner, the basic structure of the MOS transistor is completed. In such an LDD structure MOS transistor forming process, a dry etching technique using, for example, a fluorocarbon gas such as CHF ₃ gas has been conventionally used for anisotropic etching of the silicon oxide film 7 as in Patent Document 1. ing.
JP-A-6-310529

  However, when the sidewall spacer for forming the LDD is formed by using the above conventional method, the MOS transistor may be deteriorated in characteristics such as source / drain junction leakage and contact resistance variation to the region. As shown in FIG. 17, this is considered to be one of the causes that the semiconductor substrate is scraped 11 due to the over-etching in the dry etching when forming the sidewall spacer. This is because etching damage is included in the surface of the source / drain diffusion layer where the abrasion has occurred, and the impurity concentration of the diffusion layer surface is also reduced. Conventionally, the dry etching conditions have been set so as not to cut the semiconductor substrate as much as possible. However, in the prior art, as long as the semiconductor substrate is exposed to plasma during dry etching, the semiconductor substrate scraping 11 cannot be completely eliminated.

  Accordingly, an object of the present invention is to solve the above-mentioned conventional drawbacks, and in the LDD formation process of the MOS transistor, the side wall spacer is formed without the semiconductor substrate being scraped, and the side wall spacer is removed. In this case, a semiconductor device manufacturing method and a semiconductor device for removing a semiconductor substrate without scraping are provided.

In order to achieve the above object, a method of manufacturing a semiconductor device according to claim 1 of the present invention comprises a step of forming a gate electrode on a semiconductor substrate through a gate insulating film, and a SiC so as to cover the gate electrode. a step of depositing an organic-inorganic hybrid film represented by _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0), and a predetermined portion of the organic-inorganic hybrid film as an oxide layer And a step of selectively removing the oxide layer and forming a sidewall spacer made of an organic-inorganic hybrid film on the sidewall of the gate electrode.

  The method for manufacturing a semiconductor device according to claim 2 is the method for manufacturing a semiconductor device according to claim 1, wherein the predetermined portion is at least a top surface of a gate electrode and a portion of the organic-inorganic hybrid film formed on the semiconductor substrate. is there.

  The method of manufacturing a semiconductor device according to claim 3 is the method of manufacturing a semiconductor device according to claim 1, wherein the step of converting a predetermined portion of the organic-inorganic hybrid film into an oxide layer irradiates the organic-inorganic hybrid film with ions. It is performed according to the process.

  A method for manufacturing a semiconductor device according to a fourth aspect is the method for manufacturing a semiconductor device according to the third aspect, wherein the ions are oxygen ions, nitrogen ions, or inert gas ions.

  According to a fifth aspect of the present invention, there is provided a method of manufacturing a semiconductor device according to the first aspect, wherein the step of selectively removing the oxide layer is performed using a chemical solution containing fluorine.

  According to a sixth aspect of the present invention, in the method of manufacturing the semiconductor device according to the first aspect, the step of selectively removing the oxide layer is performed using a gas containing fluorine.

The method of manufacturing a semiconductor device according to claim 7, wherein a gate electrode is formed on a semiconductor substrate via a gate insulating film, and SiC _w H _x O _y N _z (w> 0, at least on a side wall of the gate electrode). a step of forming a sidewall spacer made of an organic-inorganic hybrid film represented by x ≧ 0, y> 0, z ≧ 0), a step of converting at least a surface portion of the sidewall spacer into an oxide layer, and the oxidation Selectively removing the layer.

  The method of manufacturing a semiconductor device according to claim 8 is the method of manufacturing a semiconductor device according to claim 7, wherein the step of converting the sidewall spacer into an oxide layer applies thermal energy to the sidewall spacer and supplies gas. This is done by the irradiation process.

  The method for manufacturing a semiconductor device according to claim 9 is the method for manufacturing a semiconductor device according to claim 8, wherein the gas is a gas containing oxygen or nitrogen.

  The method of manufacturing a semiconductor device according to claim 10 is the method of manufacturing a semiconductor device according to claim 7, wherein the step of converting the sidewall spacer into an oxide layer is performed by irradiating the sidewall spacer with radical species. .

  The method for manufacturing a semiconductor device according to claim 11 is the method for manufacturing a semiconductor device according to claim 10, wherein the radical species include an oxygen radical or a nitrogen radical.

  The method of manufacturing a semiconductor device according to claim 12 is the method of manufacturing a semiconductor device according to claim 7, wherein the step of converting the sidewall spacer into an oxide layer is performed by irradiating the sidewall spacer with the ions. .

  A semiconductor device manufacturing method according to a thirteenth aspect is the semiconductor device manufacturing method according to a twelfth aspect, wherein the ions include any one of oxygen ions, nitrogen ions, or inert gas ions.

  According to a fourteenth aspect of the present invention, in the method of manufacturing a semiconductor device according to the seventh aspect, the step of selectively removing the oxide layer is performed using a chemical solution containing fluorine.

  According to a fifteenth aspect of the present invention, in the method of manufacturing a semiconductor device according to the seventh aspect, the step of selectively removing the oxide layer is performed using a gas containing fluorine.

17. The semiconductor device according to claim 16, wherein a gate electrode is formed on a semiconductor substrate via a gate insulating film, and SiC _w H _x O _y N _z (w> 0, x ≧ 0, y>) is formed on a side wall of the gate electrode. (0, z ≧ 0) is formed, a side wall spacer made of an organic-inorganic hybrid film is formed, a diffusion layer is formed in the semiconductor substrate surface region adjacent to the side wall spacer, and the surface position of the diffusion layer is The surface position of the semiconductor substrate under the gate insulating film is the same as or lower than the surface position of the semiconductor substrate under the gate insulating film in a range of 7 nm or less.

According to the method for manufacturing a semiconductor device of the first aspect of the present invention, the general formula SiC _w H _x O _y N _z (w> 0, x ≧ 0, y>) formed on the semiconductor substrate such as silicon. 0, z ≧ 0) is deposited so as to cover the gate electrode, and a predetermined portion of the organic-inorganic hybrid film is converted into an oxide layer, and then a semiconductor substrate such as a chemical solution containing HF is formed. Since the oxide layer is selectively removed using a chemical solution that is not etched, and a sidewall spacer made of an organic-inorganic hybrid film is formed on the side wall of the gate electrode, a semiconductor substrate region such as a source / drain diffusion layer is not etched, Further, it can be removed without causing damage as in the prior art. As a result, leakage of the diffusion layer and variation in contact resistance can be prevented.

  According to a second aspect of the present invention, in the semiconductor device manufacturing method according to the first aspect, the predetermined portion is preferably at least a portion of the organic-inorganic hybrid film formed on the upper surface of the gate electrode and the semiconductor substrate.

  According to a third aspect of the present invention, in the method of manufacturing a semiconductor device according to the first aspect, the step of converting a predetermined portion of the organic-inorganic hybrid film into an oxide layer is preferably performed by a step of irradiating the organic-inorganic hybrid film with ions. For example, by irradiating an MSQ film, which is one of organic-inorganic hybrid films, with oxygen ions, C, H, and N constituting the MSQ film react with oxygen ions, and C, H, N, etc. of the MSQ film are oxygenated. And are removed to form an oxide layer.

  According to a fourth aspect of the present invention, in the method of manufacturing a semiconductor device according to the third aspect, the ions are preferably either oxygen ions, nitrogen ions, or inert gas ions.

  According to a fifth aspect of the present invention, in the method of manufacturing a semiconductor device according to the first aspect, the step of selectively removing the oxide layer is preferably performed using a chemical solution containing fluorine. Since the removal rate of the chemical solution containing fluorine is much higher in the oxide layer than in the MSQ film, the oxide layer can be selectively removed.

  According to a sixth aspect of the present invention, in the method of manufacturing a semiconductor device according to the first aspect, the step of selectively removing the oxide layer is preferably performed using a gas containing fluorine. A gas containing fluorine has the same effect as that of the fifth aspect.

According to the method of manufacturing a semiconductor device according to claim 7 of the present invention, the general formula SiC _w H _x O _y N _z (w> 0, x ≧ 0, y>) formed on the semiconductor substrate such as silicon. (0, z ≧ 0) is formed, a sidewall spacer made of an organic-inorganic hybrid film is formed, and at least a surface portion of the sidewall spacer is converted into an oxide layer, and then the semiconductor substrate such as a chemical solution containing HF is not etched. Since the oxide layer is selectively removed using a chemical solution, the semiconductor substrate region such as the source / drain diffusion layer can be removed without being etched and without being damaged as in the prior art. As a result, leakage of the diffusion layer and variation in contact resistance can be prevented.

  According to an eighth aspect of the present invention, in the method of manufacturing a semiconductor device according to the seventh aspect, the step of converting the sidewall spacer into an oxide layer is preferably performed by a step of applying thermal energy to the sidewall spacer and irradiating a gas. For example, if oxygen energy is irradiated to the MSQ film and heated to give thermal energy, C, H, N and oxygen in the MSQ film are removed by reaction, and the sidewall spacer is converted to an oxide layer. .

  According to a ninth aspect of the present invention, in the method of manufacturing a semiconductor device according to the eighth aspect, the gas is preferably a gas containing oxygen or nitrogen. Since the method using nitrogen gas does not form an oxide layer in a portion other than the sidewall spacer of the semiconductor device as in the case of oxygen gas, it can be used even when it is not desirable to form an oxide layer in an extra portion. There is an advantage that you can.

  According to a tenth aspect of the present invention, in the method for manufacturing a semiconductor device according to the seventh aspect, the step of converting the sidewall spacer into the oxide layer is preferably performed by a step of irradiating the sidewall spacer with radical species. In this case, an oxide layer is formed by the reactivity of the radical itself.

  According to an eleventh aspect of the present invention, in the method for manufacturing a semiconductor device according to the tenth aspect, the radical species preferably includes an oxygen radical or a nitrogen radical. In the case of irradiation with oxygen radicals or nitrogen radicals, an oxide layer is formed by the reactivity of the radicals themselves, so that the sidewall spacer can be converted into an oxide layer at a low temperature of 200 ° C. or lower. Therefore, it is very effective for a fine element pattern process in which a comprehensive heat treatment history (thermal budget) during a semiconductor integrated circuit manufacturing process such as source / drain activation is severe.

  According to a twelfth aspect of the present invention, in the method of manufacturing a semiconductor device according to the seventh aspect, the step of converting the sidewall spacer into the oxide layer is preferably performed by a step of irradiating the sidewall spacer with ions. As in the third aspect, the sidewall spacer is converted into an oxide layer.

  According to a thirteenth aspect of the present invention, in the method of manufacturing a semiconductor device according to the twelfth aspect, the ions preferably include any one of oxygen ions, nitrogen ions, or inert gas ions.

  According to a fourteenth aspect of the present invention, in the method of manufacturing a semiconductor device according to the seventh aspect, the step of selectively removing the oxide layer is preferably performed using a chemical solution containing fluorine. Similar to the fifth aspect, the oxide layer can be selectively removed.

  According to a fifteenth aspect of the present invention, in the method of manufacturing a semiconductor device according to the seventh aspect, the step of selectively removing the oxide layer is preferably performed using a gas containing fluorine.

According to the semiconductor device of the sixteenth aspect of the present invention, the organic / inorganic represented by SiC _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0) on the side wall of the gate electrode. A sidewall spacer made of a hybrid film is formed, a diffusion layer is formed in a semiconductor substrate surface region adjacent to the sidewall spacer, and the surface position of the diffusion layer is the same as the surface position of the semiconductor substrate under the gate insulating film, or Since it is lower than the surface position of the semiconductor substrate under the gate insulating film in the range of 7 nm or less, it is possible to prevent the leakage of the diffusion layer and the variation in the contact resistance. That is, after the formation of the sidewall spacer and before the end of the diffusion process of the semiconductor integrated circuit, the surface of the source / drain diffusion layer is exposed to various chemical solutions. The shape cut by about ˜5 nm, that is, the surface of the source / drain diffusion layer region is lowered by 2 to 5 nm, and is preferably 0 nm. This amount is far less than about 7 to 15 nm, which is a total of 5 to 10 nm for the dry etching contribution and 2 to 5 nm for the chemical treatment process in the side wall spacer forming method using the conventional dry etching technique. Does not affect resistance.

  A first embodiment of the present invention will be described with reference to FIGS. 1A to 1E are process cross-sectional views illustrating a process for manufacturing a MOS transistor having a very small gate length in the first embodiment of the present invention.

The main point of the manufacturing method according to the first embodiment of the present invention is that the general formula SiC _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0) deposited on the upper surface and side surface of the gate electrode. The surface of the organic / inorganic hybrid film represented by the following is irradiated with oxygen ions, nitrogen ions, or inert gas ions to convert the surface into an oxide layer, and then the oxide layer is selectively removed to form a sidewall spacer. It is. FIG. 1 shows the manufacturing process of a MOS transistor in the case of irradiation with oxygen ions. However, in the case of irradiation with nitrogen ions and inert gas ions, only the process (c) is different. Same as for irradiation. FIG. 3 shows a cross-sectional view of the step (c) of irradiating nitrogen ions, and FIG. 4 shows a cross-sectional view of the step (c) of irradiating inert gas ions, particularly Ar ions.

First, as shown in FIG. 1A, a known photolithography technique and a dry etching technique are applied to a gate electrode 102 made of, for example, a 200 nm polysilicon film on a semiconductor substrate 100 via a 2 nm gate oxide film 101, for example. Use to form. Next, self-alignment is performed by ion implantation (for example, P ⁺ is 5 × 10 ¹³ / cm ² ) using the N-type diffusion layers 103 and 104 having a low impurity concentration as part of the source and drain as a mask for the gate electrode 102. To form.

Next, as shown in FIG. 1B, one of the organic-inorganic hybrid films described above so as to cover the surface of the substrate 105 to be processed is SiC _x O _y (x> 0, y> 0). An MSQ (methylsilsesquioxane) film 106 shown is deposited by, for example, 60 nm by plasma CVD. Next, as shown in FIG. 1C, for example, oxygen ions 107 are directed toward the surface of the MSQ film 106 so as to be substantially perpendicular to the main surface of the semiconductor substrate, and thereby a predetermined portion of the MSQ film 106 is irradiated. That is, the surface portion is converted into the oxide layer 108. This process is performed in the same manner even when nitrogen ions are irradiated instead of oxygen ions. In this manner, the surface portion of the first MSQ film 106 becomes the oxide layer 108, and the MSQ film remains under the oxide layer 108. Next, as shown in FIG. 1D, the oxide layer 108 is selectively removed using, for example, a chemical solution containing 5% of HF to form a sidewall spacer 109 made of an MSQ film. Next, as shown in FIG. 1E, by using the gate electrode 102 and the side wall spacer 109 as a mask, other sources and drains are formed by an ion implantation method (for example, As ⁺ 5 × 10 ¹⁵ / cm ² ). The basic structure of the MOS transistor is completed by forming the high-concentration diffusion layers 110 and 111 to be parts in a self-aligned manner.

  The process of this embodiment is characterized by the processes (c) and (d). The method for forming the oxide layer 108 shown in FIG. 1 (c) will be described more specifically. In order to form the oxide layer 108, a plasma processing apparatus as shown in FIG. 2 is used.

  The plasma processing apparatus will be described. As shown in FIG. 2, a first high frequency power source 202 is connected to a processing chamber 201 that is grounded and whose inner wall is covered with an insulator such as ceramic, alumina, or quartz. An induction coil (upper electrode) 203 to which one high frequency power is applied is provided. When the first high frequency power is applied to the induction coil 203, inductively coupled plasma is generated inside the processing chamber 201. On the other hand, a sample stage (lower electrode) 205 to which a second high-frequency power is applied from the second high-frequency power source 204 is provided at the bottom of the processing chamber 201, and is directed to the sample stage 205 by the second high-frequency power. Ion energy is controlled. Although not shown, a temperature control device that controls the temperature of the sample table 205 in the range of about 0 ° C. to + 80 ° C. with a refrigerant or the like is provided inside the sample table 205. A processing gas is introduced into the processing chamber 201 from an inlet (not shown) through a mass flow controller (not shown), and the pressure in the processing chamber 201 is a turbo pump (not shown). In the range of 0.1 Pa to 10 Pa. The substrate to be processed on which the MSQ film 106 is deposited is placed on the sample stage 205 inside such a plasma processing apparatus, and the first and second high frequency powers are applied to the upper electrode and the lower electrode to apply the MSQ film. 106 is irradiated with oxygen ions 107 substantially perpendicularly to the main surface of the semiconductor substrate to replace the MSQ film 106 with the oxide layer 108. Here, by controlling the second high-frequency power, the incident ion energy can be adjusted, and the formation amount of the oxide layer 108 can be adjusted to a predetermined value.

When irradiating oxygen ions as specific conditions, for example, pressure: 0.6 Pa, first high frequency power: 1000 W, second high frequency power: 300 W, O ₂ flow rate: 100 ml / min, sample stage temperature: 60 ° C. In this case, an oxide layer 108 of about 60 nm can be formed on the MSQ film 106. In this case, since the pressure is low and the incident anisotropy of oxygen ions is strong, and the oxygen ions 107 are irradiated in the vertical direction with respect to the MSQ film 106 by the bias by the second high frequency power, the oxide layer 108 is in the vertical direction. Formation proceeds.

By irradiating oxygen ions into membrane represented a MSQ film in generalized formula _{SiC w H x O y N z} (w> 0, x ≧ 0, y> 0, z ≧ 0), constituting an MSQ film C, H, N reacts with oxygen ions,
SiCHON + O ⁺ → SiO _x (x = 1 to 2) + CO ₂ ↑ + H ₂ O ↑ + NO ↑ + etc ↑
Through this reaction, an oxide layer is formed.

Further, in the case of irradiation with nitrogen ions, a plasma processing apparatus as shown in FIG. 2 is also used. As specific conditions, for example, pressure: 0.6 Pa, first high frequency power: 1000 W, second high frequency power: 300 W By applying N ₂ flow rate: 100 ml / min and sample stage temperature: 60 ° C., an oxide layer 302 of about 60 nm can be formed on the MSQ film 106 by nitrogen ions 301 as shown in FIG. When the MSQ film of SiC _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0) is irradiated with nitrogen ions, C, H, N and nitrogen ions constituting the MSQ film are React,
SiCHON + N ⁺ → SiO _x (x = 1 to 2) + N ₂ ↑ + HCN ↑ + CN ↑ + etc ↑
Through this reaction, an oxide layer is formed.

In addition, irradiation with inert gas ions such as Ar ions is also performed by the plasma processing apparatus shown in FIG. 2. Specific conditions include, for example, pressure: 0.6 Pa, first high-frequency power: 1000 W, and second high-frequency power: 500 W. By applying Ar flow rate: 100 ml / min and sample stage temperature: 60 ° C., an oxide layer 402 of about 60 nm can be formed on the MSQ film 106 by Ar ions 401 as shown in FIG. _{SiC w H x O y N z} (w> 0, x ≧ 0, y> 0, z ≧ 0) is irradiated with Ar ions MSQ film in the form of, C constituting the MSQ film, H, N-inert When gas ions are sputtered,
SiCHON + Ar ⁺ → SiO _x (x = 1 to 2) + N ₂ ↑ + H ₂ ↑ + CO ₂ ↑ + etc ↑
Through this reaction, an oxide layer is formed.

In the above process, C, H, and N contained in the MSQ film are combined with oxygen or nitrogen to become a gas, diffuse from the MSQ film to the processing chamber, and are exhausted to the outside. Alternatively, it is sputtered by Ar ions and exhausted to the outside as a gas such as nitrogen, hydrogen or CO ₂ . It is considered that only the SiO component remains on the surface of the MSQ film and is converted into an oxide layer. Further, when the process of converting the surface layer of the MSQ film into the oxide layer 108 is seen, the Si—CH ₃ bonds constituting the MSQ film 106 are Si—O bonds, Si—OH bonds by oxygen ions, nitrogen ions, and Ar ions. It is thought that it is formed by changing to. One feature of the structure of the present invention as described above, after forming the pattern of the organic-inorganic hybrid film, but is to alter the surface portion of the film to the oxide layer, actually for example oxygen ions O ₂ plasma After irradiating the MSQ film, which is one of the organic-inorganic hybrid films, when the irradiated part is examined by FTIR (Fourier transform infrared absorption spectrum), the oxygen ion irradiation time is shown in FIG. Only the Si—O bond spectrum appears strongly and remains. This indicates that C, H, etc. of the MSQ film are removed by the oxygen ion irradiation and actually converted into an oxide layer.

  Thus, although Si—O and Si—OH bonds exist in the oxide layer, there are many dangling bonds and the like, and the density is lower than that of a CVD silicon oxide film, a thermal oxide film, etc. FIG. It easily binds to F- in the HF-containing chemical solution used in step d). On the other hand, the MSQ film 106 has a property that it is difficult to react with F− because electrons are supplied to the Si atoms from the methyl group and the number of dangling bonds is reduced. For this reason, in the step of FIG. 1D, if an HF-containing chemical solution is used, this oxide layer can be selectively removed easily from the remaining MSQ film. That is, the removal rate by the chemical solution is much higher in the oxide layer 108 than in the MSQ film 106, so that the oxide layer 108 can be selectively removed (selectivity ratio: about 10).

  As described above, in the manufacturing method according to the present embodiment, the sidewall spacer 109 can be formed by wet etching using an HF-containing chemical solution that does not substantially etch the semiconductor substrate. You can avoid the problem of doing. Ultimately, junction leakage of MOS transistors and increase in contact resistance can be prevented.

The surface of the source / drain diffusion layer is exposed to various chemicals after the formation of the sidewall spacers of the MOS transistor and before the end of the diffusion process of the semiconductor integrated circuit, and the gate insulating film is formed by chemical treatment such as NH ₄ OH + H ₂ O _2. The shape of the semiconductor substrate below or below the sidewall spacer is cut by about 2 to 5 nm, that is, the surface of the source / drain diffusion layer region is 2 to 5 nm lower, and 0 nm is desirable. This amount is far less than about 7 to 15 nm, which is a total of 5 to 10 nm for the dry etching contribution and 2 to 5 nm for the chemical treatment process in the side wall spacer forming method using the conventional dry etching technique. Does not affect resistance.

  The method of irradiating nitrogen ions has an advantage that the oxide layer 302 can be formed even when a resist pattern or the like exists on the semiconductor substrate other than the gate electrode and the resist is etched by oxygen ions. There is. Even in the method of irradiating with Ar ions, the oxide layer 402 can be formed even when a resist pattern or the like exists in a region other than the gate electrode and oxygen ions cannot be used. In particular, since Ar ions are inactive, a reaction layer such as an oxide layer or a nitride layer is not formed in a portion exposed to ions on the semiconductor substrate other than the MSQ film 106. Therefore, it is very effective when it is not desired to form a reaction layer in a part other than the MSQ film 106.

In this embodiment, it is described that the formation amount of the oxide layer is controlled by controlling the second high frequency power. However, the processing pressure in the processing chamber, the first high frequency power, the gas flow rate, and the temperature of the sample stage are described. The amount of oxide layer formed can also be controlled by controlling parameters such as processing time. For example, when the first high-frequency power, the gas flow rate, and the processing time are increased, the supply amount of oxygen ions, nitrogen ions, or Ar ions increases, so that the amount of oxide layer formation increases. Further, when the temperature of the sample stage is raised, the reaction between oxygen ions or nitrogen ions and elements such as C and H constituting the MSQ film is promoted, so that the amount of oxide layer formed increases and Ar ions are increased. In this case, the generated gas such as CO ₂ and H ₂ generated from the components of the MSQ film is easily volatilized by sputtering of Ar ions, so that the amount of formation of the oxide layer is accelerated and increased.

Further, instead of oxygen gas as irradiation ion gas, oxygen and carbon compounds (CO, CO ₂ etc.), oxygen and nitrogen compounds (NO, NO ₂ , N ₂ O, N ₂ O ₂ etc.), oxygen and Use hydrogen compounds (H ₂ O, H ₂ O _2, etc.) and replace nitrogen gas as irradiation ion gas with oxygen and nitrogen compounds (NO, NO ₂ , N ₂ O, N ₂ O _2, etc.) , Nitrogen and hydrogen compounds (NH ₃ , N ₂ H ₂ etc.), nitrogen and carbon compounds (C ₂ N ₂ etc.) are used, and instead of Ar gas, He, Ne, Kr, Xe etc. Even if an inert gas is used, the same effect can be obtained.

  A second embodiment of the present invention will be described with reference to FIGS. 6 and 7 are process cross-sectional views illustrating a method for manufacturing a semiconductor device according to the second embodiment of the present invention, and show a cross section of a MOS transistor portion as in the first embodiment.

In this embodiment, after the side wall made of the MSQ film is formed on the side surface of the gate electrode in the same manner as the method described in the first embodiment, the side wall spacer is converted into an oxide layer and removed. It is a configuration. First, as shown in FIG. 6A, a known photolithography technique and a dry etching technique are used to form a gate electrode 502 made of, for example, a 200 nm polysilicon film on a semiconductor substrate 500 via a 2 nm gate oxide film 501. Use to form. Next, self-alignment is performed by ion implantation (for example, P ⁺ is 5 × 10 ¹³ / cm ² ) using the N-type diffusion layers 503 and 504 having a low impurity concentration as a part of the source and drain as a mask for the gate electrode 502. To form.

Next, as shown in FIG. 6B, an MSQ (methyl silsesquioxane) film 506 represented by SiC _x O _y (x> 0, y> 0) so as to cover the surface of the substrate 505 to be processed. Is deposited by CVD, for example, to 60 nm. This MSG film may contain hydrogen and nitrogen and be represented by the general formula SiC _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0). Next, as shown in FIG. 6C, the MSQ film 506 is irradiated with, for example, oxygen ions 507 using various methods shown in FIGS. The portion is converted into the first oxide layer 508. Next, as shown in FIG. 6D, the first oxide layer 508 is selectively removed using, for example, a chemical solution containing 5% of HF to form sidewall spacers 509.

Next, as shown in FIG. 6E, by using the gate electrode 502 and the side wall spacer 509 as a mask, other sources and drains are formed by an ion implantation method (for example, As ⁺ 5 × 10 ¹⁵ / cm ² ). High-concentration diffusion layers 510 and 511 are formed in a self-aligned manner.

  Next, as shown in FIG. 7A, the sidewall spacer 509 is irradiated with the oxygen gas 512, and at the same time, the substrate to be processed is heated to give a thermal energy, so that the sidewall spacer 509 is subjected to the second oxidation. Convert to layer 513. In the example of FIGS. 6 and 7, the conditions for converting the entire sidewall spacer 509 into the oxide layer 513 are taken. Next, as shown in FIG. 7B, when the second oxide layer 513 is selectively removed using a chemical solution containing, for example, 5% HF, the basic structure of the MOS transistor without the sidewall spacer is completed. .

  The feature of this embodiment is a process drawing 7A, and the formation of the second oxide layer 513 shown in FIG. 7A will be described in more detail. In order to form the second oxide layer 513, a heater heating type heat treatment apparatus as shown in FIG. 8 is used.

  In FIG. 8, a sample stage 602 is installed in a processing chamber 601, and a temperature control device including a heater and a thermocouple is provided inside the sample stage 602. The temperature of the sample stage 602 is set to 400 ° C. to 1000 ° C. (The illustration is omitted). Gas is introduced into the processing chamber 601 from the inlet 604 via the mass flow controller 603, and the pressure in the processing chamber is controlled to a range of about 50 Pa to 200 Pa by a dry pump (not shown).

When performing the process of FIG. 7A, a substrate to be processed on which a side wall spacer made of an MSQ film is formed is placed on a sample stage 602, and the side wall spacer 509 is irradiated with oxygen gas 512 and the sample stage. Thermal energy is applied from 602 and converted into the second oxide layer 513. By applying, for example, pressure: 100 Pa, O ₂ flow rate: 1000 ml / min, and sample stage temperature: 700 ° C. as specific conditions, an oxide layer 513 of about 60 nm can be formed on the sidewall spacer 509. In this case, the oxygen gas isotropically enters the sidewall spacer, so that the sidewall spacer 509 is isotropically converted into the second oxide layer 513. In this conversion process, oxygen reacts with C, H, N constituting the MSQ film,
SiCHON + O → SiO _x (x = 1 to 2) + CO ₂ ↑ + H ₂ O ↑ + NO ↑ + etc ↑
It is thought that the following reaction occurs.

In the above embodiment, the amount of conversion of the sidewall spacer 509 into the oxide layer in the step of FIG. 7A can be controlled by controlling the temperature of the sample stage. It is also possible to control parameters such as gas flow rate and processing time. For example, when the processing pressure, the gas flow rate, and the processing time are increased, the supply amount of oxygen increases, so the amount of oxide layer formed increases. Step 7 was used an oxygen gas as a process gas (a), a compound of oxygen and carbon (CO, etc. CO _2), compounds of oxygen and nitrogen _{(NO, NO 2, N 2} O, etc. N ₂ O ₂ ), And using an oxygen and hydrogen compound (H ₂ O, H ₂ O _2, etc.), the same effect can be obtained.

  In the manufacturing process of the MOS transistor described with reference to FIGS. 6 and 7, oxygen gas is used to convert the side wall spacer 509 of FIG. 7A into the second oxide layer 513, but other gases are used. That is, nitrogen gas can also be used.

9 corresponds to FIG. 7A in the manufacturing process of the MOS transistor according to the second embodiment of the present invention, and is a process sectional view showing a process of irradiating nitrogen gas to convert it into an oxide layer. Nitrogen gas 702 is a second oxide layer. Also in the case of irradiation with nitrogen gas, the heater heating type heat treatment apparatus shown in FIG. 8 is used to irradiate the side wall spacer 509 with nitrogen gas 701 and to apply thermal energy from the sample stage 602 to the semiconductor substrate to perform the second oxidation. Convert to layer 702. As specific conditions, for example, when a pressure: 100 Pa, an N ₂ flow rate: 1000 ml / min, and a sample stage temperature: 700 ° C. are applied, a second oxide layer 702 of about 60 nm can be formed on the sidewall spacer 509.

Since nitrogen gas is irradiated isotropically as in the case of FIG. 7A, the sidewall spacer 509 is isotropically converted into the second oxide layer 702. When the MSQ film is irradiated with nitrogen gas and heated to give thermal energy, C, H, and N of the MSQ film react with nitrogen,
SiCHON + N → SiO _x (x = 1 to 2) + N ₂ ↑ + HCN ↑ + CN ↑ + etc ↑
In this process, the sidewall spacer is considered to be converted into the second oxide layer.

Since the method using nitrogen gas does not form an oxide layer in a portion other than the sidewall spacer 509 of the semiconductor device unlike the case of oxygen gas, it should be used even when it is not desirable to form an oxide layer in an extra portion. There is an advantage that can be. Further, instead of nitrogen gas as the oxide layer forming gas, oxygen and nitrogen compounds (NO, NO ₂ , N ₂ O, N ₂ O ₂ etc.), nitrogen and hydrogen compounds (NH ₃ , N ₂ H ₂ etc.) ), And using a compound of nitrogen and carbon (such as C ₂ N ₂ ), the same effect can be obtained. Further, although the heater heating method is used as the sample table heating method, the same effect can be obtained even if a lamp heating method heat treatment apparatus using a halogen lamp or the like is used.

  A third embodiment of the present invention will be described with reference to FIGS. In the second embodiment, as the step of converting the sidewall spacer made of the MSQ film into the second oxide layer (step corresponding to FIG. 7A), when the substrate is heated to a high temperature and given thermal energy, The method of irradiating oxygen gas or nitrogen gas at the same time was described. However, since various methods other than the above can be considered as the method for converting to the second oxide layer, they will be described in the present embodiment.

In the following description, only the step of converting the sidewall spacer into the second oxide layer will be described in correspondence with FIG. The process flow when these are applied to the MOS transistor manufacturing process is the same as that of FIGS. 6A to 6E and FIG. 7B except for the process of FIG.
(1) Conversion to Second Oxide Layer Using Oxygen Radical or Nitrogen Radical FIG. 10 is a process cross-sectional view showing a process of converting a sidewall spacer made of an MSQ film into a second oxide layer using oxygen radical. 801 is an oxygen radical, and 802 is a second oxide layer. FIG. 12 is a process cross-sectional view showing a process of converting a sidewall spacer made of an MSQ film into a second oxide layer using nitrogen radicals, where 1001 is a nitrogen radical and 1002 is a second oxide layer. . This process uses the plasma processing apparatus shown in FIG.

  In FIG. 11, the processing chamber 901 of the plasma processing apparatus is grounded, and a gas whose flow rate is controlled by a mass flow controller (not shown) is introduced into the plasma generation chamber 903 from the introduction pipe 902. A high frequency power source 904 is connected to the plasma generation chamber 903, and gas is converted into plasma by the power supplied from the high frequency power source 904 to generate ions and radicals. Since the treatment chamber 901 and the plasma generation chamber 903 are separated from each other, ions disappear in the middle and only radicals reach the treatment chamber 902. A sample stage 905 is installed in the processing chamber 901. Although not shown, the temperature of the sample stage 905 is controlled within a range of about 100 ° C. to 300 ° C. by a heater or the like inside the sample stage 905. A temperature control device is provided. Furthermore, the pressure in the processing chamber 901 is controlled to a range of about 50 Pa to 200 Pa by a dry pump (not shown).

A semiconductor substrate on which a side wall spacer made of an MSQ film is formed is placed on a sample stage 905 inside the plasma processing apparatus, and the oxygen radical 801 or the nitrogen radical 1001 is irradiated on the side wall spacer 509 to form second oxide layers 802 and 1002. Convert to When oxygen radicals are used, specific conditions such as pressure: 100 Pa, high-frequency power: 1000 W, O ₂ flow rate: 1000 ml / min, sample stage temperature: 150 ° C. are applied to oxidize the sidewall spacer 509 to about 60 nm. Can be converted to layer 802. By irradiating the side wall spacer with oxygen radicals, C, H, and N of the MSQ film react with oxygen radicals,
SiCHON + O ^* → SiO _x (x = 1 to 2) + CO ₂ ↑ + H ₂ O ↑ + NO ↑ + etc ↑
It is considered that the second oxide layer is converted in the process.

When nitrogen radicals are used, for example, by applying the conditions of pressure: 100 Pa, high frequency power: 1000 W, N ₂ flow rate: 1000 ml / min, sample stage temperature: 150 ° C., the sidewall spacer 509 is oxidized by about 60 nm. Layer 1002 can be converted. When nitrogen radical irradiation is performed, C, H, and N of the MSQ film react with nitrogen radicals,
SiCHON + N ^* → SiO _x (x = 1 to 2) + N ₂ ↑ + HCN ↑ + CN ↑ + etc ↑
It is considered that the second oxide layer is converted in the reaction process. In the above reaction, the oxygen radical 801 and the nitrogen radical 1001 are isotropically irradiated in the processing chamber, so that the sidewall spacer 509 is also isotropically converted into the second oxide layer 802 or 1002.

  In the case of irradiation with oxygen radicals or nitrogen radicals, an oxide layer is formed by the reactivity of the radicals themselves, so that the sidewall spacer 509 can be converted to the second oxide layer 802 at a low temperature of 200 ° C. or lower. Therefore, it is very effective for a fine element pattern process in which a comprehensive heat treatment history (thermal budget) during a semiconductor integrated circuit manufacturing process such as source / drain activation is severe.

In the above embodiment, oxygen gas is used as the oxygen radical generating gas. However, oxygen and carbon compounds (CO, CO _2, etc.), oxygen and nitrogen compounds (NO, NO ₂ , N ₂ O, N ₂ O _2, etc.) ), Oxygen and hydrogen compounds (H ₂ O, H ₂ O _2, etc.) may be used, and nitrogen gas is used as a nitrogen radical generating gas, but oxygen and nitrogen compounds (NO, NO ₂ , N ₂ O, N ₂ O ₂ etc.), nitrogen and hydrogen compounds (NH ₃ , N ₂ H ₂ etc.), nitrogen and carbon compounds (C ₂ N ₂ etc.) can be used to obtain the same effect. Can do. In particular, when oxygen radicals are used, there is a problem that the resist is etched if there is a resist pattern or the like on the semiconductor substrate other than the side wall spacer at the time of radical irradiation. There is an advantage that an oxide layer can be formed. Moreover, although high frequency electric power was used for radical production | generation, you may use a microwave.
(2) Conversion to second oxide layer using oxygen ions, nitrogen ions, or inert gas ions FIG. 13 shows a step of converting a sidewall spacer made of an MSQ film into a second oxide layer using oxygen ions. FIG. 11 is a process cross-sectional view showing the oxygen ions 1101 and the second oxide layer 1102. FIG. 14 is a process cross-sectional view showing a process of converting a sidewall spacer made of an MSQ film into a second oxide layer using nitrogen ions, wherein 1201 is a nitrogen ion and 1202 is a second oxide layer. Further, FIG. 15 is a process sectional view showing a process of converting the sidewall spacer made of the MSQ film into the second oxide layer by using inert gas ions, particularly Ar ions, 1301 being Ar ions, 1302 being second ions It is an oxide layer. The plasma processing apparatus shown in FIG. 2 is used for irradiation with oxygen ions, nitrogen ions, or Ar ions. In this case, a substrate on which a side wall spacer made of an MSQ film is formed on a sample stage 205 in the processing chamber 201 is used. It is installed, oxygen or nitrogen plasma is generated by the first high frequency power source 202 and a high frequency voltage is applied to the substrate from the second high frequency power source 204 to control oxygen / nitrogen / Ar ion energy in the incident plasma.

When performing oxygen ion irradiation, for example, pressure: 0.6 Pa, first high-frequency power: 1000 W, second high-frequency power: 300 W, O ₂ flow rate: 100 ml / min, sample stage temperature: 60 ° C. By application, an oxide layer 1102 having a thickness of about 60 nm can be formed. Then, by irradiating the MSQ film with oxygen ions, C, H, and N of the MSQ film react with oxygen ions,
SiCHON + O ⁺ → SiO _x (x = 1 to 2) + CO ₂ ↑ + H ₂ O ↑ + NO ↑ + etc ↑
It is considered that the second oxide layer is converted in the reaction process.

When performing nitrogen ion irradiation, for example, conditions of pressure: 0.6 Pa, first high frequency power: 1000 W, second high frequency power: 300 W, N2 flow rate: 100 ml / min, sample stage temperature: 60 ° C. are applied. As a result, an oxide layer 1202 of about 60 nm can be formed. When the MSQ film is irradiated with nitrogen ions, C, H, N constituting the MSQ film react with nitrogen ions,
SiCHON + N ⁺ → SiO _x (x = 1 to 2) + N ₂ ↑ + HCN ↑ + CN ↑ + etc ↑
It is considered that the second oxide layer is converted in the reaction process. In the case of irradiation with Ar ions, for example, the conditions of pressure: 0.6 Pa, first high frequency power: 1000 W, second high frequency power: 500 W, Ar flow rate: 100 ml / min, sample stage temperature: 60 ° C. By applying, an oxide layer 1302 of about 60 nm can be formed. By irradiating the MSQ film with inert gas (Ar) ions, Ar ions sputter C, H, and N of the MSQ film,
SiCHON + Ar ⁺ → SiO _x (x = 1 to 2) + N ₂ ↑ + H ₂ ↑ + CO ₂ ↑ + etc ↑
It is considered that the second oxide layer is converted in the reaction process. Here, for the conversion of the MSQ film to the oxide layer, the conversion amount of the oxide layer can be adjusted to a predetermined value by controlling the second high-frequency power applied to the substrate side. The amount of oxide layer formed can also be adjusted by controlling parameters such as the processing pressure 201, the first high-frequency power, the gas type, the gas flow rate, the temperature of the sample stage, and the processing time.

  In the method using ion irradiation, incident energy of oxygen ions 1101 and nitrogen ions 1201 themselves is used as reaction energy for forming the second oxide layer, and Ar ions 1301 use a sputtering effect on the sidewall spacer 509. It is not necessary to apply heat or other energy from the outside, and the second oxide layers 1102, 1202, and 1302 can be converted at a lower temperature. Therefore, as in (1), the thermal budget is effective for a severe process. When this method is performed, the surface of the source / drain diffusion layers 503, 504, 510, and 511 of the semiconductor substrate 500 is also irradiated with oxygen ions 1101, nitrogen ions 1201, or Ar ions. It was judged that there was no.

In the above embodiment, oxygen gas is used as the oxygen ion gas. However, oxygen and carbon compounds (CO, CO _2, etc.), oxygen and nitrogen compounds (NO, NO ₂ , N ₂ O, N ₂ O _2). Etc.), oxygen and hydrogen compounds (H ₂ O, H ₂ O ₂ etc.) can be used, and in addition to the nitrogen gas shown above as nitrogen ion gas, oxygen and nitrogen compounds (NO, NO ₂ , N ₂ O, N ₂ O ₂ etc.), nitrogen and hydrogen compounds (NH ₃ , N ₂ H ₂ etc.), nitrogen and carbon compounds (C ₂ N ₂ etc.) can be used, and as an inert gas ion source The same effect can be obtained by using a gas such as He, Ne, Kr, or Xe instead of Ar.

  In particular, in the case of Ar ion / nitrogen ion irradiation, a second oxide layer 1302 is formed even when there is a resist pattern or the like on the semiconductor substrate other than the sidewall spacer at the time of ion irradiation and oxygen ion irradiation for etching the resist cannot be performed. it can. At the same time, since Ar ions are inactive, it is very effective even when it is not preferable to form a reaction layer such as an oxide layer or a nitride layer in a portion exposed to ion irradiation other than the sidewall spacer. .

  As described above, the second oxide layer formed by converting the sidewall spacer made of the MSQ film by the method described in the second and third embodiments of the present invention is the same as the oxide layer formed in the first embodiment. Since the film has the same film properties, the semiconductor is etched at a very high etching rate compared with a silicon oxide film formed by a normal CVD method or thermal oxidation by wet etching with a chemical solution containing HF in the process of FIG. 7B. It can be easily removed selectively from the substrate material. In particular, in the oxygen ion / nitrogen ion / inert gas (Ar) ion irradiation method in (2) of the third embodiment, the second oxide layers 1102, 1202 formed by the oxygen / nitrogen / inert gas ion sputtering effect. Since many of the Si-O and Si-OH bonds of 1302 are broken, the density is particularly low, and the HF-containing chemical solution in the process of FIG. It can be easily removed.

  Further, in the MOS transistor manufacturing process according to the second and third embodiments of the present invention, the HF-containing chemical solution is used in both the sidewall spacer forming process (FIG. 6C) and the sidewall spacer removing process (FIG. 7A). Therefore, the source / drain diffusion layer made of silicon or the like is hardly etched. Therefore, since the semiconductor substrate is not scraped as in the prior art, the source / drain diffusion layer leakage and the increase in contact resistance against these can be prevented. The steps of the second and third embodiments are added with a step of removing the sidewall spacer once formed. For example, in a semiconductor integrated circuit, when the gate electrodes are arranged with a narrow interval on the pattern layout and a contact hole is to be formed between the gates, the contact hole cannot be formed if a side wall spacer is present. This is occurring in pattern integrated circuits. In such a case, it is necessary to remove the sidewall spacer, and this embodiment can be carried out without damaging the substrate.

  In all the embodiments described above, the method of selectively removing the second oxide layer using a chemical solution containing fluorine has been described. However, the same effect can be obtained even if selective removal using a gas containing fluorine is performed. be able to. In the first embodiment and the second embodiment (2), inductively coupled plasma is used for ion generation. However, ECR (Electron Cyclotron Resonance) type plasma, capacitively coupled plasma, microwave excitation type is used. Similar effects can be obtained by using plasma or ion irradiation using a known ion implantation method. In the embodiment of the present invention, the method for forming the sidewall spacer for forming the LDD has been described. However, the present invention can be applied to other sidewall formation.

  A method for manufacturing a semiconductor device and a semiconductor device according to the present invention include miniaturization for forming an element without damaging a substrate, including a case where a MOS transistor having an LDD sidewall spacer is formed without damaging a semiconductor substrate. It is useful for highly integrated semiconductor devices.

FIG. 5D is a process cross-sectional view illustrating the manufacturing method of the semiconductor device according to the first embodiment of the invention. It is an apparatus schematic diagram of a plasma processing apparatus. FIG. 6 is a process cross-sectional view illustrating a process of converting to an oxide layer with nitrogen ions according to the first embodiment of the present invention. FIG. 5 is a process cross-sectional view illustrating a process of converting to an oxide layer with Ar ions according to the first embodiment of the present invention. It is a Fourier-transform infrared absorption spectrum figure. It is process sectional drawing explaining the manufacturing method of the semiconductor device by the 2nd Embodiment of this invention. FIG. 7 is a process sectional view subsequent to FIG. 6; It is the apparatus schematic of a heat processing apparatus. It is process sectional drawing explaining the process converted into an oxide layer with the nitrogen gas by the 2nd Embodiment of this invention. It is process sectional drawing explaining the process converted into an oxide layer with the oxygen radical by the 3rd Embodiment of this invention. It is an apparatus schematic diagram of a plasma processing apparatus. It is process sectional drawing explaining the process converted into an oxide layer with the nitrogen radical by the 3rd Embodiment of this invention. It is process sectional drawing explaining the process converted into an oxide layer with the oxygen ion by the 3rd Embodiment of this invention. It is process sectional drawing explaining the process converted into an oxide layer with the nitrogen ion by the 3rd Embodiment of this invention. It is process sectional drawing explaining the process converted into an oxide layer with Ar ion by the 3rd Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the conventional semiconductor device. It is sectional drawing explaining the subject in the manufacturing method of the conventional semiconductor device.

Explanation of symbols

1,100,500 Semiconductor substrate 2,101,501,502 Gate insulating film 3,102 Gate electrode 4,5,9,10,103,104,110,111,503,504,510
511 N type diffusion layer 6, 105, 505 Substrate 7, 106, 506 MSQ (methyl silsesquioxane) film 8, 109, 509 Side wall spacer 11 Semiconductor substrate scraping 107, 507, 1101 Oxygen ions 108, 302, 402 Oxide layer 201, 601, 901 Processing chamber 202 First high frequency power source 203 Coil 204 Second high frequency power source 301, 1201 Nitrogen ion 401, 1301 Ar ion 508 First oxide layer 512 Oxygen gas 513, 702, 802, 1002 , 1102, 1202, 1302 Second oxide layer 602, 905 Sample stage 603 Mass flow controller 604 Gas inlet 701 Nitrogen gas 801 Oxygen radical 902 Gas inlet tube 903 Plasma generation chamber 904 High-frequency power source 1001 Nitrogen radical

Claims (16)

A step of forming a gate electrode on a semiconductor substrate via a gate insulating film; and SiC _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0) so as to cover the gate electrode. ), A step of converting a predetermined portion of the organic-inorganic hybrid film into an oxide layer, and selectively removing the oxide layer to form an organic layer on the side wall of the gate electrode. A method for manufacturing a semiconductor device, including a step of forming a sidewall spacer made of an inorganic hybrid film.   2. The method of manufacturing a semiconductor device according to claim 1, wherein the predetermined portion is at least a portion of the organic-inorganic hybrid film formed on the upper surface of the gate electrode and the semiconductor substrate.   The method of manufacturing a semiconductor device according to claim 1, wherein the step of converting a predetermined portion of the organic-inorganic hybrid film into an oxide layer is performed by irradiating the organic-inorganic hybrid film with ions.   The method of manufacturing a semiconductor device according to claim 3, wherein the ions are oxygen ions, nitrogen ions, or inert gas ions.   2. The method of manufacturing a semiconductor device according to claim 1, wherein the step of selectively removing the oxide layer is performed using a chemical solution containing fluorine.   The method for manufacturing a semiconductor device according to claim 1, wherein the step of selectively removing the oxide layer is performed using a gas containing fluorine. Forming a gate electrode on the semiconductor substrate via a gate insulating film, and at least SiC _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0) on the side wall of the gate electrode; A step of forming a sidewall spacer comprising an organic-inorganic hybrid film represented by the following: a step of converting at least a surface portion of the sidewall spacer into an oxide layer; and a step of selectively removing the oxide layer. Device manufacturing method.   8. The method of manufacturing a semiconductor device according to claim 7, wherein the step of converting the sidewall spacer into an oxide layer is performed by applying thermal energy to the sidewall spacer and irradiating a gas.   The method for manufacturing a semiconductor device according to claim 8, wherein the gas is a gas containing oxygen or nitrogen.   8. The method of manufacturing a semiconductor device according to claim 7, wherein the step of converting the sidewall spacer into an oxide layer is performed by irradiating the sidewall spacer with radical species.   The method of manufacturing a semiconductor device according to claim 10, wherein the radical species includes an oxygen radical or a nitrogen radical.   8. The method of manufacturing a semiconductor device according to claim 7, wherein the step of converting the sidewall spacer into an oxide layer is performed by irradiating the sidewall spacer with the ions.   The method of manufacturing a semiconductor device according to claim 12, wherein the ions include any one of oxygen ions, nitrogen ions, or inert gas ions.   8. The method of manufacturing a semiconductor device according to claim 7, wherein the step of selectively removing the oxide layer is performed using a chemical solution containing fluorine.   8. The method of manufacturing a semiconductor device according to claim 7, wherein the step of selectively removing the oxide layer is performed using a gas containing fluorine. A gate electrode is formed on a semiconductor substrate via a gate insulating film, and expressed by SiC _w H _x O _y N _z (w> 0, x ≧ 0, y> 0, z ≧ 0) on the side wall of the gate electrode. A sidewall spacer made of an organic-inorganic hybrid film is formed, a diffusion layer is formed in the semiconductor substrate surface region adjacent to the sidewall spacer, and the surface position of the diffusion layer is the position of the semiconductor substrate under the gate insulating film A semiconductor device, characterized by being lower than the surface position of the semiconductor substrate under the gate insulating film within a range equal to or less than 7 nm.

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