JP2017203076A - Cmp polisher and polishing method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CMP polisher that can secure a sufficiently good polishing rate on a polishing target film containing silicon oxide, and provide a CMP polishing method that polishes a polishing target film at a sufficiently good polishing rate, using such a CMP polisher.SOLUTION: A CMP polisher contains cerium oxide particles, trivalent cerium compound particles and water.SELECTED DRAWING: None

Description

  The present invention relates to a CMP abrasive and a polishing method using the same.

  The CMP (Chemical Mechanical Polishing) technique is a technique essential for forming shallow trench isolation, planarizing a premetal insulating film or an interlayer insulating film, forming a plug and a buried metal wiring, etc. in a semiconductor device manufacturing process. It has become.

  Various polishing liquids for CMP used in the CMP are known. Categorical polishing liquid containing cerium oxide (ceria) particles or cerium hydroxide particles as abrasive grains and silica containing silicon oxide (silica) particles as abrasive grains Known are an abrasive based polishing liquid, an alumina polishing liquid containing aluminum oxide (alumina) particles as abrasive grains, a resin particle polishing liquid containing organic resin particles as abrasive grains, and the like.

  As a polishing liquid for polishing an insulating material such as silicon oxide in a semiconductor element manufacturing process, a ceria-based polishing liquid is often used in terms of a higher polishing rate for an inorganic insulating material than a silica-based polishing liquid. Yes. (See Patent Document 1). Furthermore, in order to control the polishing rate and improve the flatness of the polished film after polishing, a technique of adding an additive to the polishing agent using cerium oxide has been disclosed (see Patent Document 2).

Japanese Patent Laid-Open No. 10-106994 Japanese Patent Laid-Open No. 08-22970

  However, when a polishing film containing silicon oxide is polished by a conventional CMP abrasive using cerium oxide, there is a problem that a good polishing rate cannot always be obtained.

  Accordingly, an object of the present invention is to provide a CMP abrasive that can obtain a sufficiently good polishing rate for a film to be polished containing silicon oxide. It is another object of the present invention to provide a CMP polishing method for polishing a film to be polished at a sufficiently good polishing rate using such a CMP abrasive.

  The present invention is a CMP abrasive containing cerium oxide particles, trivalent cerium compound particles and water.

  By providing the above-described configuration, the CMP abrasive of the present invention can obtain a sufficiently good polishing rate when used as a CMP abrasive for polishing a film to be polished containing silicon oxide. is there.

  The trivalent cerium compound particles are preferably trivalent cerium organic acid salts.

  The present invention also relates to a CMP polishing method for polishing a film to be polished while supplying the CMP abrasive between the polishing cloth and the film to be polished formed on the substrate. According to this method, it is possible to polish at a sufficiently good polishing rate, and when the film to be polished contains silicon dioxide, a more excellent effect can be obtained.

  According to the present invention, a CMP abrasive capable of obtaining a sufficiently good polishing rate can be provided. Further, it is possible to provide a CMP polishing method for polishing a film to be polished at a sufficiently good polishing rate using such a CMP abrasive.

  Hereinafter, embodiments of the present invention will be described in detail.

  The CMP abrasive according to the present embodiment contains cerium oxide particles, trivalent cerium compound particles, and water.

(Cerium oxide particles)
The CMP abrasive according to this embodiment uses cerium oxide particles as the first abrasive particles (abrasive grains). The type of cerium oxide particles is not particularly limited, but it is preferable to include polycrystalline cerium oxide particles having a grain boundary. Polycrystalline cerium oxide particles having a grain boundary become fine during polishing and exhibit a behavior in which active surfaces appear one after another, so that a film to be polished containing silicon oxide (hereinafter referred to as “silicon oxide film”). The polishing rate can be improved. A method for producing cerium oxide having a grain boundary is described in detail in, for example, republished patent WO99 / 31195.

  In the present embodiment, the cerium oxide particles may be obtained by any manufacturing method. For example, as a method for producing cerium oxide particles, a method in which a cerium compound such as cerium carbonate is baked or oxidized with hydrogen peroxide or the like can be applied. The method for the firing step is not particularly limited, and a method such as a sintering method using a rotary kiln or an electric furnace can be used. In this case, the firing temperature is preferably 350 to 900 ° C.

  When the cerium oxide particles produced by these methods are aggregated, the aggregated particles may be mechanically pulverized. As a pulverization method, for example, a dry pulverization method using a jet mill or the like (refer to “Chemical Engineering Papers”, Vol. 6, No. 5, 1980, pages 527 to 532) or a wet pulverization method using a planetary bead mill or the like is preferable.

  When such cerium oxide particles are applied to a CMP abrasive, it is preferable to obtain a cerium oxide slurry by dispersing it in water as a main dispersion medium. Examples of the dispersion method include a method using a homogenizer, an ultrasonic disperser, a wet ball mill, and the like in addition to a dispersion treatment with a normal stirrer.

  Furthermore, the particle size of the cerium oxide particles in the cerium oxide slurry obtained by the above method may be adjusted by a known method. For example, the cerium oxide slurry can be micronized by centrifuging with a small centrifuge, forcibly sedimenting, and taking out only the supernatant. Further, the fine particles can be removed by taking out the precipitated side by decantation and adding a dispersion medium such as water thereto.

  In addition, the particles may be formed into fine particles by using a high-pressure homogenizer that causes the cerium oxide particles in the dispersion medium to collide with each other at a high pressure.

  The average particle diameter of the cerium oxide particles is preferably 50 to 300 nm from the viewpoint of increasing the polishing rate of the silicon oxide film. The average particle size is preferably 300 nm or less, more preferably 280 nm or less, further preferably 250 nm or less, and particularly preferably 200 nm or less because polishing scratches are less likely to occur. On the other hand, from the viewpoint of improving the polishing rate, the average particle size is preferably 50 nm or more, more preferably 70 nm or more, and further preferably 80 nm or more.

  Here, the “average particle size” is the median value of the volume distribution obtained by directly measuring the CMP abrasive with a laser diffraction particle size distribution meter. More specifically, for example, the average particle diameter (D50) can be obtained using “Microtrac MT3300EXII” manufactured by Nikkiso Co., Ltd.

  In addition, the said average particle diameter can be controlled by the manufacturing conditions, classification conditions, etc. of cerium oxide. In addition, in the present embodiment, the average particle diameter is the particle diameter of the cerium oxide particles in a state where the CMP abrasive is used, and can be adjusted depending on the type and amount of additives, pH of the CMP abrasive, which will be described later. it can.

  The content (concentration) of the cerium oxide particles is preferably 0.1 to 10% by mass with respect to the total mass of the CMP abrasive. The concentration of the cerium oxide particles is preferably 10% by mass or less, more preferably 8% by mass or less, further preferably 6% by mass or less, particularly preferably 5% by mass or less, because the particles are less likely to aggregate. % Or less is most preferable. On the other hand, the concentration of the cerium oxide particles is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, further preferably 0.3% by mass or more, and 0.5% by mass from the viewpoint of improving the polishing rate. % Or more is particularly preferable.

(Trivalent cerium compound particles)
The CMP abrasive | polishing agent which concerns on this embodiment contains a trivalent cerium compound particle as a 2nd abrasive particle (abrasive grain). The trivalent cerium compound particles preferably contain an organic acid salt of trivalent cerium.

  The following reasons can be considered as a mechanism that enables the silicon oxide film to be polished at high speed by using the above trivalent cerium compound particles. When trivalent cerium compound particles and tetravalent cerium oxide particles coexist, electrons are transferred between two kinds of particles having different valences, and it is estimated that a part of the cerium atoms of cerium oxide becomes trivalent. It is considered that high-speed polishing is possible because the highly reactive cerium oxide generated in this manner reacts with the silicon oxide film surface and Si—O—Ce bonds are easily generated.

  The trivalent cerium compound particles are preferably obtained by reacting a cerium (III) compound with an organic acid. For example, cerium carbonate hydrate [Ce2 (CO3) 3 · 8H2O] and malonic acid can be mixed and reacted at 1: 3 (molar ratio) in water to prepare cerium malonate particles. Further, for example, trivalent cerium nitrate hydrate [Ce (NO3) 3 · 6H2O] and ammonium oxalate · monohydrate are mixed and reacted in water at a ratio of 2: 3 (molar ratio). Can adjust cerium oxide particles.

  The trivalent cerium compound preferably has a water solubility of 0.1 g / 100 mL or less. More specifically, cerium salts of lactic acid, malonic acid, oxalic acid, malic acid, maleic acid, tartaric acid, succinic acid, citric acid, salicylic acid, and benzoic acid can be mentioned.

  The content of the trivalent cerium compound particles is preferably 0.1 to 10% by mass with respect to the total mass of the CMP abrasive. The concentration of the trivalent cerium compound particles is preferably 10% by mass or less, more preferably 8% by mass or less, still more preferably 6% by mass or less, and particularly preferably 5% by mass or less because the particles are less likely to aggregate. 4 mass% or less is the most preferable. On the other hand, the concentration of the trivalent cerium compound particles is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, further preferably 0.3% by mass or more, from the viewpoint of improving the polishing rate. 5 mass% or more is especially preferable.

  The average particle diameter of the trivalent cerium compound particles is preferably 20 to 500 nm from the viewpoint of increasing the polishing rate of the silicon oxide film. The average particle size is preferably 500 nm or less, more preferably 400 nm or less, even more preferably 300 nm or less, and particularly preferably 250 nm or less because polishing scratches are less likely to occur. On the other hand, from the viewpoint of improving the polishing rate, the average particle size is preferably 20 nm or more, more preferably 40 nm or more, and further preferably 50 nm or more.

  Here, the “average particle size” is the median value of the volume distribution obtained by directly measuring the CMP abrasive with a laser diffraction particle size distribution meter. More specifically, for example, the average particle diameter (D50) can be obtained using “Microtrac MT3300EXII” manufactured by Nikkiso Co., Ltd.

  The average particle size can be controlled by the production conditions, classification conditions, etc. of the trivalent cerium compound particles.

(Medium)
The medium for the CMP abrasive is not particularly limited, but a medium containing water as a main component is preferable, and more specifically, deionized water, ion-exchanged water, ultrapure water, or the like is preferable. Note that the CMP abrasive may further contain a solvent other than water, for example, a polar solvent such as ethanol, acetic acid, and acetone, if necessary.

(PH adjuster)
The CMP abrasive | polishing agent which concerns on this embodiment may contain the pH adjuster further. By using an acid or a base as the pH adjuster, the desired pH of the CMP abrasive can be obtained. In some cases, it has a function as a dispersant and can control the average particle diameter of the cerium oxide particles.

  Although it does not specifically limit as a pH adjuster, The thing which can mainly contribute to adjustment of pH and does not have a bad influence on a grinding | polishing characteristic is preferable. From such a viewpoint, examples of the pH adjuster include inorganic acids, inorganic bases, organic acids, and organic bases. Examples of the inorganic acid include inorganic acids such as nitric acid, sulfuric acid, hydrochloric acid, phosphoric acid, and boric acid. Examples of the inorganic base include sodium hydroxide, potassium hydroxide, calcium hydroxide, and aqueous ammonia. The organic acid is preferably a monocarboxylic acid, and specific examples include monocarboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, acrylic acid, benzoic acid, and picolinic acid.

(Other)
The CMP abrasive may further contain other components as necessary for the purpose of further improving the selectivity of the polishing rate of the silicon oxide film to the silicon nitride film, or for the purpose of improving other polishing characteristics. .

  Examples of other components include surfactants and water-soluble polymers. Examples of the water-soluble polymer include polyacrylic acid, polyacrylic acid copolymer, polyacrylate, polyacrylic acid copolymer salt, polymethacrylic acid, and polymethacrylate. These addition amounts are preferably set in amounts that do not hinder the effect of increasing the polishing rate by adding trivalent cerium compound particles.

(CMP abrasive type)
The manufacturing method for the CMP abrasive according to this embodiment is not particularly limited, and any CMP polishing agent may be used as long as it has the above-described characteristics when used for polishing. . Except when used for polishing (during storage, transportation, etc.), for example, it can have forms such as the following normal type, concentrated type, and two-component type.

  The “normal type” is a type that can be used as it is as a CMP abrasive without pretreatment such as dilution during polishing. Although this normal type production method is not particularly limited, for example, 1000 g of an abrasive with 0.5% by mass of cerium oxide content in use and 0.5% by mass of trivalent cerium compound particles is used. In the case of production, in the normal type, 5 g of cerium oxide particles and 5 g of trivalent cerium compound particles may be added to the total amount of the abrasive.

  The “concentrated type” is a product that enhances the convenience of production, storage and transportation of CMP abrasives by concentrating the components contained in the normal type. Just before use, this concentrated type is mixed with water so that the contained components have the desired content, and has the same liquid properties (eg, pH and particle size) as the normal type, and polishing properties (eg, polishing rate). And stirring for an arbitrary time so that the ratio can be reproduced. By setting it as such a concentration type, since the volume required for storage and transportation can be reduced according to the degree of concentration, the cost for storage and transportation can be reduced.

  In the case of the concentrated type, the concentration ratio with respect to the normal type is preferably 1.5 to 20 times from the viewpoint of storage stability and convenience. If the concentration is excessively large, the cerium oxide particles are likely to aggregate or the additive is not dissolved in the medium. Therefore, the upper limit of the concentration ratio is preferably 20 times, more preferably 17 times, even more preferably 15 times. Double is more preferable, and 5 times is particularly preferable. On the other hand, if it is too thin, there are merits in storage and transportation, but there are cases where the demerit that takes time and effort for dilution is larger than that in the normal type. Therefore, the lower limit of the concentration ratio is preferably 1.5 times, more preferably 2 times, further preferably 3 times, and particularly preferably 4 times.

  A point to be noted in the production of the concentrated abrasive is that the pH changes before and after dilution when diluted with water during use. For example, when an abrasive having the same pH as that of a normal type is prepared from a concentrated type of abrasive, the pH of water is theoretically 7 (however, actual water has dissolved carbon dioxide, and only water Therefore, when the concentrated type having a pH of 5.5 or lower is used, for example, only an abrasive having a pH higher than that can be obtained after dilution. Therefore, it is preferable to adjust the pH to a low level in advance in a concentrated abrasive so that the desired pH can be easily obtained during use.

  Furthermore, the “two-component type” means, for example, that the content of the abrasive is divided into the liquid A and the liquid B, and these are mixed into a single abrasive before a certain period of use. According to such a two-component type, it is easy to avoid the ease of aggregation of cerium oxide particles in the case of the concentrated type. The liquid A and the liquid B in the two-component type can each contain a contained component at an arbitrary ratio. In the case of the two-liquid type, there is no particular limitation on how to separate them. For example, the liquid A is a slurry containing cerium oxide particles + trivalent cerium compound particles (+ pH adjusting agent), and the liquid B is other components (+ pH adjusting agent). What was divided | segmented as an addition liquid containing is suitable.

  When a certain time elapses after the CMP abrasives are mixed with each other, the polishing characteristics may deteriorate due to aggregation of cerium oxide particles or the like. In such a case, it is effective to apply the two-liquid type. Further, in order to reduce the volume of the liquid A and the liquid B, the liquid A and the liquid B can be made to be concentrated types, respectively. In this case, a dilute solution containing water as a main component can be further added during mixing of the liquid A and the liquid B to form one CMP abrasive. The concentration ratio of liquid A and liquid B and their pH are arbitrary, and the final polishing agent only needs to have the same liquid composition and polishing characteristics as the normal type composition.

<Substrate Polishing Method and Substrate>
In the polishing step, for example, the CMP abrasive is supplied between the material to be polished and the polishing pad in a state where the material to be polished of the substrate having the material to be polished is pressed against the polishing pad (polishing cloth) of the polishing surface plate. Then, the material to be polished is polished by relatively moving the substrate and the polishing surface plate. In the polishing step, for example, at least a part of the material to be polished is removed by polishing. The shape of the material to be polished, which is an object to be polished, is not particularly limited, but is, for example, a film shape (film to be polished).

  Examples of materials to be polished include inorganic insulating materials such as silicon oxide; organic insulating materials such as organosilicate glass and wholly aromatic ring-based low-k materials; and stopper materials such as silicon nitride and polysilicon. Materials and organic insulating materials are preferable, and inorganic insulating materials are more preferable. The silicon oxide film can be obtained by a low pressure CVD method, a plasma CVD method, or the like. The silicon oxide film may be doped with an element such as phosphorus or boron. The surface of the material to be polished (surface to be polished) preferably has irregularities. In the substrate polishing method according to this embodiment, the uneven surface of the material to be polished is preferentially polished, and a substrate with a flattened surface can be obtained.

(Polishing method)
Hereinafter, the polishing method according to this embodiment will be further described by taking as an example a polishing method for a semiconductor substrate on which each polishing material is formed. In the polishing method according to the present embodiment, as a polishing apparatus, a general polishing apparatus having a holder capable of holding a substrate such as a semiconductor substrate having a surface to be polished and a polishing surface plate to which a polishing pad can be attached. Can be used. For example, a motor or the like whose rotation speed can be changed is attached to each of the holder and the polishing surface plate. Examples of the polishing apparatus include a polishing apparatus manufactured by APPLIED MATERIALS (trade names: Mira-3400, Reflexion LK) and a polishing apparatus manufactured by Ebara Corporation (trade name: FREX-300).

  As the polishing pad, a general nonwoven fabric, foam, non-foam, or the like can be used. As a material of the polishing pad, polyurethane, acrylic, polyester, acrylic-ester copolymer, polytetrafluoroethylene, polypropylene, polyethylene, poly-4-methylpentene, cellulose, cellulose ester, polyamide (for example, nylon (trade name) and Aramid), polyimide, polyimide amide, polysiloxane copolymer, oxirane compound, phenol resin, polystyrene, polycarbonate, epoxy resin and the like can be used. As the material of the polishing pad, in particular, foamed polyurethane and non-foamed polyurethane are preferable from the viewpoint of polishing speed and flatness. The polishing pad may be grooved so that the abrasive is collected.

  Although there is no limitation on the polishing conditions, the rotation speed of the polishing platen is preferably 200 min-1 (rpm) or less so that the semiconductor substrate does not pop out, and the polishing pressure (working load) applied to the semiconductor substrate causes polishing scratches. From the viewpoint of sufficiently suppressing this, 100 kPa or less is preferable. During polishing, it is preferable to continuously supply the polishing agent to the polishing pad with a pump or the like. Although there is no restriction | limiting in this supply amount, it is preferable that the surface of a polishing pad is always covered with the abrasive | polishing agent.

  The semiconductor substrate after polishing is preferably washed thoroughly under running water to remove particles adhering to the substrate. For cleaning, dilute hydrofluoric acid or ammonia water may be used in addition to pure water, and a brush may be used to improve cleaning efficiency. Further, after cleaning, it is preferable to dry the semiconductor substrate after water droplets adhering to the semiconductor substrate are removed using a spin dryer or the like.

  In this way, by polishing the inorganic insulating layer, which is a film to be polished, with the above-described polishing agent, surface irregularities can be eliminated and a smooth surface can be formed over the entire surface of the semiconductor substrate. A semiconductor substrate having a desired number of layers can be manufactured by repeating such a process a predetermined number of times.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to this.

(Cerium oxide particles)
40 kg of cerium carbonate hydrate was put in an alumina container and calcined in air at 830 ° C. for 2 hours to obtain 20 kg of a yellowish white calcined powder. As a result of phase identification by an X-ray diffraction method, this fired powder was confirmed to be a powder composed of cerium oxide particles (hereinafter referred to as “cerium oxide particle powder”). The particle diameter of the obtained cerium oxide particle powder was 20 to 100 μm.

  20 kg of the obtained cerium oxide particle powder was dry-ground using a jet mill. The specific surface area of the powder after dry pulverization was measured by the BET method and found to be 9.4 m 2 / g.

(Cerium oxide mixture)
In a container, 15.0 kg of the cerium oxide powder obtained above and 84.7 kg of deionized water are added and mixed. Further, 0.3 kg of 1N acetic acid is added and stirred for 10 minutes. Obtained.

(Concentrated cerium oxide slurry)
The obtained cerium oxide mixed solution was fed to another container over 30 minutes. Meanwhile, ultrasonic irradiation was performed on the cerium oxide mixed solution at an ultrasonic frequency of 400 kHz in the pipe for feeding the liquid.

  The cerium oxide mixed solution fed via ultrasonic irradiation was pulverized by a bead mill pulverizer, and then diluted so that the solid content concentration of cerium oxide was 10% by mass to obtain a concentrated cerium oxide slurry.

  The obtained concentrated cerium oxide slurry was measured using a laser diffraction particle size distribution analyzer (trade name: Microtrac MT3300EXII, manufactured by Nikkiso Co., Ltd.), and the average particle size of the CMP abrasive was 148 nm. .

(Cerium oxalate particles)
After mixing 0.43 kg of cerium (III) nitrate hexahydrate and 1 kg of deionized water in a glass container, add 0.21 kg of ammonium oxalate monohydrate and mix for 15 minutes. Got. The cerium oxalate contained in this dispersion was collected by centrifugation and dried to obtain cerium oxalate.

(Concentrated cerium oxalate slurry)
In the container, 50 g of the cerium oxalate particle powder obtained above and 450 g of deionized water were added and mixed, and 0.1 g of acetic acid was further added and stirred for 10 minutes to obtain a cerium oxalate mixture. The obtained cerium oxalate mixed solution was pulverized by a bead mill pulverizer to obtain a concentrated cerium oxalate slurry having a solid content concentration of 10% by mass.

Example 1
To 50 g of the concentrated cerium oxide slurry obtained above (solid content concentration 10% by mass), 940 g of deionized water and 10 g of the concentrated cerium oxalate slurry obtained above (solid content concentration 10% by mass) were added, By mixing, a CMP abrasive was obtained.

  About the obtained CMP abrasive | polishing agent, when measured using the laser diffraction type particle size distribution measuring apparatus (The Nikkiso Co., Ltd. make, brand name: Microtrac MT3300EXII), the value of the average particle diameter of CMP abrasive | polishing agent was 180 nm.

(Example 2)
To 167 g of the cerium oxide mixed solution (solid content concentration of 15% by mass) obtained above, 328 g of deionized water and 5 g of the cerium oxalate particles obtained above were added and mixed. Next, this dispersion was pulverized with a bead mill pulverizer to obtain a CMP abrasive.

  About the obtained CMP abrasive | polishing agent, when measured using the laser diffraction type particle size distribution measuring apparatus (The Nikkiso Co., Ltd. make, brand name: Microtrac MT3300EXII), the value of the average particle diameter of CMP abrasive | polishing agent was 150 nm.

(Comparative Example 1)
950 g of deionized water was mixed with 50 g of the concentrated cerium oxide slurry (solid content concentration 10% by mass) obtained above to obtain a CMP abrasive.

(Evaluation wafer)
A commercially available silicon oxide film wafer (evaluation wafer) was used for the evaluation of the polishing characteristics. This wafer is manufactured by forming a silicon oxide film having a thickness of 1000 nm on a silicon substrate by a CVD method.

(Polishing experiment)
The polishing experiment was performed using a polishing apparatus (manufactured by APPLIED MATERIALS, trade name “Mira 3400”) including a substrate holder and a polishing surface plate. First, the wafer for evaluation was fixed to a substrate holder, and a polishing cloth (polishing pad) “IC-1010” (manufactured by Nitta Haas Co., Ltd.) made of a porous urethane resin was attached to a polishing surface plate. Next, the evaluation wafer was pressed against the polishing cloth and the polishing surface plate with a processing load of 20 kPa so that the silicon oxide film (insulating film or film to be polished) of the evaluation wafer was in contact with the polishing cloth. Then, the polishing surface plate and the substrate holder are operated at 93 rpm and 87 rpm, respectively, while dropping the CMP abrasive prepared in the above examples and comparative examples on the polishing cloth at a rate of 200 mL / min. As a result, the evaluation wafer was polished for 30 seconds. The polished evaluation wafer was sufficiently washed with pure water and then dried.

  The polishing rate was calculated by measuring the SiO2 film thickness of the evaluation wafer before and after polishing and dividing by the polishing time.

  For the measurement, an optical interference film thickness apparatus (manufactured by Nanometrics Japan Co., Ltd., trade name “Nanospec AFT-5100”) was used.

  Table 1 shows polishing rate values when the CMP abrasives obtained in Examples 1 and 2 and Comparative Example 1 were used.

  As shown in Table 1, when the CMP abrasive of the example was used, the polishing rate value of the silicon oxide film was larger than when the CMP abrasive of the comparative example was used. That is, according to the CMP abrasive | polishing agent of this invention, in the grinding | polishing of the to-be-polished film | membrane containing a silicon oxide, it became clear that a sufficiently favorable grinding | polishing speed | rate is obtained.

Claims (6)

  A CMP abrasive containing cerium oxide particles, trivalent cerium compound particles and water.   The CMP abrasive | polishing agent of Claim 1 in which the said trivalent cerium compound particle | grain contains the organic acid salt of at least trivalent cerium.   The CMP abrasive | polishing agent of Claim 1 or 2 for grinding | polishing the to-be-polished film | membrane containing a silicon oxide. A CMP polishing method for polishing a polishing target film while supplying a CMP abrasive between a polishing cloth and a polishing target film formed on a substrate,
A CMP polishing method, wherein the CMP abrasive comprises cerium oxide particles, trivalent cerium compound particles, and water.   The CMP polishing method according to claim 4, wherein the trivalent cerium compound particles contain at least an organic acid salt of trivalent cerium.   6. The CMP polishing method according to claim 4, wherein the film to be polished is a film containing silicon oxide.