Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K3/00—Materials not provided for elsewhere
  • C09K3/14—Anti-slip materials; Abrasives
  • C09K3/1454—Abrasive powders, suspensions and pastes for polishing
  • C09K3/1463—Aqueous liquid suspensions
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
  • H10P52/00—Grinding, lapping or polishing of wafers, substrates or parts of devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
  • B24B37/00—Lapping machines or devices; Accessories
  • B24B37/04—Lapping machines or devices; Accessories designed for working plane surfaces
  • B24B37/042—Lapping machines or devices; Accessories designed for working plane surfaces operating processes therefor
  • B24B37/044—Lapping machines or devices; Accessories designed for working plane surfaces operating processes therefor characterised by the composition of the lapping agent
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09G—POLISHING COMPOSITIONS; SKI WAXES
  • C09G1/00—Polishing compositions
  • C09G1/02—Polishing compositions containing abrasives or grinding agents
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
  • H10P95/00—Generic processes or apparatus for manufacture or treatments not covered by the other groups of this subclass
  • H10P95/06—Planarisation of inorganic insulating materials
  • H10P95/062—Planarisation of inorganic insulating materials involving a dielectric removal step

Definitions

• Polishing agent for semiconductor integrated circuit device polishing method, and method for manufacturing semiconductor integrated circuit device
• the present invention relates to a polishing technique used in a manufacturing process of a semiconductor integrated circuit device. More specifically, the present invention relates to a polishing technique used in a manufacturing process of a semiconductor integrated circuit device including a diacid-based silicon material layer.
• CMP chemical mechanical polishing
• CMP is an interlayer dielectric film (ILD film: Inter-Level Dielectrics) flatness, shallow trench isolation (STI), tungsten plug formation, copper and low dielectric constant film. It is used in a multilayer wiring forming process comprising Recently, it has also begun to be applied to the planarization of insulating films (PMD: Pre-Metal Dielectrics) that have been performed before the formation of metal wiring, which previously used the reflow method by heat treatment.
• ILD film Inter-Level Dielectrics
• Insulating films such as ILD, STI, and PMD often use silicon dioxide.
• silica abrasive grains are generally used as abrasive grains used in CMP abrasives. It was.
• the surface of a film to be polished (hereinafter also referred to as a film to be polished) of a semiconductor integrated circuit device forms a concavo-convex pattern under the influence of the concavo-convex such as wiring underneath when the film is laminated. To do.
• the film to be polished is formed with a large film thickness.
• semiconductor integrated circuit device manufacturing which raises the cost of film formation and lowers throughput.
• borophosphosilicate glass (BPSG), borosilicate glass (BSG), phosphosilicate glass (PSG), etc. are used in the PMD process, and the polishing rate of these films is the other material. Since it is much larger than that, it is necessary to make a film with a large film thickness in advance and polish it to achieve planarization.
• FIG. Fig. 3 (a) shows a structure in which a silicon dioxide film 2, a polysilicon film 3 and a BPSG film 4 are stacked on a silicon substrate 1, and the convex portion 5 is formed on the surface of the B PSG film 4 due to the influence of the polysilicon film 3.
• FIG. 6 is a partial cross-sectional view of a semiconductor integrated circuit device showing a state in which a recess 6 is formed. This is the state before polishing.
• the BPSG film surface is polished in such a configuration, the BPSG film is more prone to polish the concave portion than the convex portion. ) In many cases. Therefore, at present, the thickness of the BPSG film 4 is increased and polished to reduce the unevenness.
• a semiconductor integrated circuit device including a silicon dioxide-based material layer in particular, generally has a higher polishing rate than other materials, and includes any deviation between a BPSG film, a BSG film, and a PSG film.
• the semiconductor integrated circuit device has a problem that it is difficult to flatten the surface to be polished.
• CMP abrasives using cerium oxide particles as abrasive grains have been studied as abrasive grains used in CMP abrasives.
• the cerium oxide abrasive has a high polishing rate due to the chemical reaction between the cerium oxide on the layer surface and the Si—O bond SiO part on the surface of the film to be polished, and is expected to improve throughput in the manufacturing process of semiconductor devices.
• surfactants, water-soluble polymers, water-soluble small molecules, etc. are added to improve the dispersibility of the cerium oxide polishing agent and improve the flatness of the polished surface.
• Patent Document 1 SiO, SiON, SiOF, boron phosphoric acid glass, and phosphorus
• an organic compound having a carboxyl group or a hydrophilic group having a salt power of a carboxyl group has been proposed.
• Patent Document 2 a low molecular weight additive that exhibits cationic properties and has a water-soluble organic low molecular force such as primary amine, secondary amine, tertiary amine, or quaternary ammonium compound is also selected. Additives have been proposed, and it is said that polishing can be performed with high efficiency, high speed, and easy process management in CMP technology that flattens ILD films and STI insulating films.
• Patent Document 3 proposes to contain two or more additives consisting of a water-soluble nitrogen-containing compound and a water-soluble ionic organic compound, and this abrasive damages the surface to be polished. It is said to be a CMP polishing agent suitable for polishing ILD films, insulating films for STI, etc., which can achieve high flatness at high speed, has excellent storage stability and is easy to manage.
• water-soluble nitrogen-containing compounds include primary amines, secondary amines, tertiary amines, quaternary ammonia, polyburpipyridone, N-alkyl-2-pyrrolidone, aliphatic ratatam and aliphatic dicarboxylic acids. It is an acid imide.
• water-soluble organic compounds include free —COOM groups, phenolic —OH groups, —SOM groups, —OSO M groups, —POM groups, and —POM groups (only
• M is a compound having a hydrogen atom, NH or a metal atom.
• Patent Document 1 shows examples of polishing a diacid-based silicon film, and there are no examples of BPSG films, BSG films, and PSG films that are difficult to flatten. Since the additive of Patent Document 1 is a key-on type, it does not adsorb on the diacid-caine film, BPS G film, BSG film, and PSG film that are negatively charged in water, so that a sufficient film cannot be formed. . Even if a hard carbon dioxide film can be flattened, a soft BPSG film, BSG film, or PSG film can actually However, it is impossible to flatten a patterned semiconductor integrated circuit device having a significantly high polishing rate.
• Patent Document 2 since the additive of Patent Document 2 is a cationic additive, it is possible to form a film, but it is a low-molecular additive, so the film property is not sufficient.
• Semiconductors of BPSG film, BSG film, and PSG film are also used.
• An integrated circuit device cannot be flattened.
• Patent Document 3 proposes two or more types of additives, water-soluble nitrogen-containing compounds and water-soluble organic compounds, but water-soluble nitrogen-containing compounds are substantially the same as low-molecular additives in Patent Document 2.
• the semiconductor integrated circuit device cannot be flattened because the polishing rate of BPSG film, BSG film, and PSG film is extremely large.
• the pH of the CMP abrasive is preferably 3 to 9, more preferably 7.0 to 9.0, from the viewpoints of stability, selective polishing, workability, handling, and the like. In this pH range, there is a problem that the polishing rate of BPSG film, BSG film and PSG film cannot be controlled effectively.
• Patent Document 1 Japanese Patent Publication No. 3278532
• Patent Document 2 Japanese Patent Laid-Open No. 2001-7061
• Patent Document 3 Japanese Patent Laid-Open No. 2001-185514
• Patent Document 4 Japanese Patent Laid-Open No. 11 12561
• Patent Document 5 Japanese Patent Laid-Open No. 2001-35818
• the present invention solves the above-described problems, and the pattern dependence of the polishing rate is extremely small when polishing the surface to be polished of the diacid-based material layer in the manufacture of a semiconductor integrated circuit device.
• An object of the present invention is to provide an abrasive and a polishing method capable of realizing high planarization by preferentially polishing the convex portion while suppressing polishing of the concave portion. Still other objects and advantages of the present invention will become apparent from the following description.
• a chemical mechanical polishing abrasive for polishing a surface to be polished in the manufacture of a semiconductor integrated circuit device wherein the surface to be polished is a surface to be polished of a silicon dioxide-based material layer, and the polishing agent Characterized by containing cerium oxide particles, a water-soluble polyamine and water. Abrasive to make.
• the silicon dioxide-based material layer is a borophosphate glass (BPSG) layer, a borosilicate glass (BSG) layer, or a phosphate glass (PSG) layer.
• BPSG borophosphate glass
• BSG borosilicate glass
• PSG phosphate glass
• the water-soluble polyamine force wherein the water-soluble polyether polyamine and the water-soluble polyalkylene polyamine force are one or more water-soluble polyamines that are also selected as a group force, and any one of the above (1) to (4) Abrasives.
• a polishing method for a surface to be polished in which a polishing agent is supplied to the polishing pad, the surface to be polished of the semiconductor integrated circuit device is brought into contact with the polishing pad, and polishing is performed by relative movement between the two.
• a polishing method in which a polishing surface is a surface to be polished of a diacid-based material layer and the polishing agent according to any one of (1) to (10) is used as the polishing agent.
• a method for manufacturing a semiconductor integrated circuit device comprising a step of polishing a surface to be polished by the polishing method according to (11).
• the invention's effect in manufacturing a semiconductor integrated circuit device, a convex portion while suppressing polishing of a concave portion with less pattern dependency of a polishing rate when polishing a surface to be polished of a diacid-based material layer.
• the surface to be polished can be made highly flat with an extremely small amount of polishing.
• FIG. 1 is a schematic cross-sectional side view of a semiconductor device when the semiconductor device is polished with the abrasive of the present invention.
• FIG. 2 is a diagram showing an example of a polishing apparatus applicable to the polishing method of the present invention.
• FIG. 3 is a schematic cross-sectional side view of a semiconductor device when the semiconductor device is polished with a conventional abrasive.
• FIG. 4 A schematic cross-sectional side view of a blanket wafer.
• FIG. 5 is a schematic cross-sectional side view of a patterned wafer.
• An abrasive applied to the present invention is a chemical mechanical polishing abrasive for polishing a surface to be polished of a semiconductor integrated circuit device (hereinafter also simply referred to as a semiconductor device). Contains cerium particles, a water-soluble polyamine, and water. A dispersant may coexist.
• surface to be polished means a surface of an intermediate stage that appears in the process of manufacturing a semiconductor device.
• the semiconductor device when the semiconductor device includes a diacid-based material layer, the surface to be polished of the diacid-based material layer is polished in the manufacturing process, A layer having a flat surface can be easily formed. Two or more silicon dioxide-based material layers may be included in one semiconductor device.
• FIG. 1A is a schematic cross-sectional side view of a semiconductor device showing a configuration similar to that of FIG.
• the pattern dependency of the polishing rate when polishing the polishing surface of the diacid-based material layer is extremely small, so that the progress of polishing of the concave portion is suppressed.
• FIG. 1 (b) by preferentially polishing the convex portion, as shown in FIG. 1 (b), it is possible to realize a highly flat surface with unevenness on the surface to be polished with a small amount of polishing.
• FIG. 1 (b) shows schematically in the film thickness of the BPSG film in FIG.
• the abrasive does not aggregate abrasive grains, it has excellent dispersion stability and is advantageous for polishing defects.
• cerium oxide is used as the abrasive cannon in the abrasive.
• cerium oxide particles exhibit a particularly high polishing rate in polishing silicon dioxide based materials. This consists of cerium oxide and Si-O bond SiO part on the surface of the film to be polished. This is because a chemical bond is formed between the two and a grinding force more than a mere mechanical action.
• acid-cerium abrasive grains disclosed in Patent Document 4 or Patent Document 5 can be preferably used. That is, an cerium nitrate powder obtained by preparing an alkali cerium hydroxide gel by filtering an alkali in an aqueous cerium (IV) nitrate solution, filtering, washing and baking can be preferably used. Further, the cerium oxide abrasive grains obtained by pulverizing and firing high-purity cerium carbonate, and further pulverizing and classifying the cerium carbonate can be preferably used.
• the average particle diameter (diameter) of the oxycerium abrasive grains is from 0.01 to 0.5 111, particularly from 0.02 to 0.3 / ⁇ ⁇ , in terms of polishing characteristics and dispersion stability. Is from 0.05 to 0.2 111 children. If the average particle size is too large, scratches such as scratches may easily occur on the surface of the semiconductor substrate. If the average particle size is too small, the polishing rate may be low. Moreover, since the ratio of the surface area per unit volume is large, it is easily affected by the surface condition. Depending on conditions such as ⁇ and additive concentration, aggregation may be likely. When agglomeration occurs, scratches such as scratches are likely to occur on the surface of the semiconductor substrate.
• the diacid-based material according to the present invention is a material generally containing other elements in a diacid-based material.
• the inclusion in this case means that other elements are uniformly contained.
• any element can be used as the “other element”.
• boron, phosphorus, carbon, nitrogen and fluorine can be mentioned.
• the polishing rate varies significantly depending on the concentration of the boron, so that the effects of the present invention are easily exhibited.
• concentration of phosphorous or boron or phosphorous and boron in the phosphoric acid-based material is 0.1 to The effect is large when it is in the range of 20 mass%.
• Silicon dioxide-based materials containing phosphorus or boron or phosphorus and boron can be used for chemical vapor deposition (SiOCVD).
• SiH silane
• O silane
• BH diborane
• PH phosphine
• Inorganic gas B (OCH) (trimethoxyborane), P (OCH) (trimethoxyphosphine), etc.
• a machine gas can be added simultaneously to form a film.
• Well known phosphorous or boron or phosphoric acid and boron-containing diacid-based materials include borophosphosilicate glass (BPSG), borosilicate glass (BSG), and phosphosilicate glass. (PSG), and the present invention is particularly effective when these materials are used. This is thought to be due to the adsorption effect of the water-soluble polyamine on the surface of the cerium oxide barrel and the polished surface. In other words, this effect suppresses the progress of polishing in the recesses where the polishing pressure is low, by inhibiting the chemical reaction caused by contact between the cerium oxide and the Si—O bond SiO part in the film to be polished.
• the polishing progresses preferentially, so that it is considered possible to make the surface to be polished highly flat. ing.
• BPSG is a glass mainly composed of silicon, phosphorus, boron, and oxygen. Phosphorus and boron can be changed in the range of 0.1 to 20% by mass, respectively.
• BSG is a glass mainly composed of silicon, boron and oxygen. Boron can be changed in the range of 0.1 to 20% by mass.
• PSG is a glass mainly composed of key, phosphorus and oxygen. Phosphorus can be changed in the range of 0.1 to 20% by mass.
• the category of the diacid-based material according to the present invention includes the diacid-based material itself.
• the present invention is also useful when the surface to be polished is a surface of a diacid silicon layer. In this case, polishing is possible by reducing the concentration of the water-soluble polyamine.
• the water-soluble polyamine in the abrasive may be any water-soluble compound having two or more amino groups in one molecule.
• the water solubility may be any level as long as it is completely dissolved in the abrasive liquid at the concentration used as the abrasive. Usually, it is a substance that dissolves in pure water at 1% by mass or more, preferably 5% by mass or more.
• Water-soluble polyamines are water-soluble polyether polyamines and water-soluble polyalkylene polyamines.
• the molecular weight of the water-soluble polyamine is not limited as long as the molecular weight is in the range having water solubility, but the weight average molecular weight is preferably in the range of 100 to 100,000. More preferably, it is in the range. When the weight average molecular weight is less than 100, the effect is small. If it exceeds 100,000, even if it is water-soluble, it may adversely affect the physical properties such as the fluidity of the abrasive. If it exceeds 2000, the solubility in pure water often decreases.
• Particularly preferred water-soluble polyamines are water-soluble polyether polyamines and water-soluble polyalkylene polyamines having a weight average molecular weight of 100 to 2,000.
• These water-soluble polyamines are highly effective in suppressing the polishing rate of the diacid-based material layer.
• the polishing rate is greatly reduced. Since these insulating films are low in hardness, a general silica abrasive or an abrasive using conventional cerium oxide cerium abrasives has a significantly high polishing rate and a large pattern dependency. Since the polishing progresses rapidly, a large amount of polishing is required and high flatness cannot be realized sufficiently.
• the polishing rate of the diacid-based material layer can be reduced, so that the polishing rate can be greatly reduced, and polishing of recesses with extremely small pattern dependence can be achieved.
• the polishing rate of the convex portion By preferentially polishing the convex portion while suppressing it, it becomes possible to achieve high flatness.
• the water-soluble polyamine is a water-soluble polyether polyamine having a weight average molecular weight of 100 to 2000 and a water-soluble polyalkylene polyamine having a weight average molecular weight of 100 to 2000.
• a water-soluble polyalkylene polyamine having a weight average molecular weight of 100 to 2000.
• One or more water-soluble polyamines from the viewpoint of the high dispersion stability effect on cerium oxide granules, the water-soluble polyester polyamine has a more preferred weight average molecular weight of 150 to 800, and an even more preferred weight average molecular weight of 150 to 800. 400.
• the polyether polyamine means a compound having two or more amino groups and two or more etheric oxygen atoms.
• the amino group is preferably a primary amino group (one NH 3).
• the polyether polyamine in the present invention may have two or more primary amino groups, and may have a secondary amino group (one NH—) or a tertiary amino group as an amino group. Other compounds having substantially no amino groups are preferred, especially polyethers having only two primary amino groups Diamine is preferred.
• the polyether polyamine is preferably a compound having a structure in which a hydrogen atom of a hydroxyl group of a polyhydric alcohol or polyether polyol is substituted with an aminoalkyl group.
• a divalent to hexavalent alcohol particularly, a divalent alcohol is preferred.
• polyether polyol a divalent to hexavalent polyoxyalkylene polyol, particularly, a polyoxyalkylene diol is preferable.
• aminoalkyl group examples include 2-aminoethyl group, 2-aminopropyl group, 2-amino-1-methylethyl group, 3-aminopropyl group, 2-amino-1, 1-dimethylethyl group, and 4-aminobutyl group. Groups are preferred.
• the polyhydric alcohol is preferably a dihydric alcohol having an etheric oxygen atom such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol or the like, but having 2 to 8 carbon atoms.
• Polyether polyols include polyethylene glycols such as triethylene glycol and tetraethylenedaricol (ie, polyoxyethylene diol), polypropylene glycols such as tripropylene glycol and tetrapropylene glycol (ie, polyoxypropylene diol), and poly (o Preferred is a polyether diol in which the repeating unit is an oxyalkylene group having 2 to 6 carbon atoms, such as a polyoxyalkylene diol having two or more types of oxyalkylene groups such as xypropylene / oxyethylene) diol.
• the polyalkylene polyamine means a compound in which three or more amino groups are bonded via an alkylene group.
• the terminal amino group is preferably a primary amino group, and the amino group in the molecule is preferably a secondary amino group. More preferably, it is a linear polyalkylene polyamine having a primary amino group at both molecular terminals and having one or more secondary amino groups in the molecule.
• These plurality of amino group-bonded portions may be the same or different from each other, or the two amino-group-bonded portions bonded to the primary amino groups at both ends are the same and other It is preferable that it is different from the bonding part between amino groups.
• the number of carbon atoms contained in one amino group-linked moiety is preferably 2-8, and the number of carbon atoms contained in the two amino-group bonded moieties bonded to the primary amino groups at both ends is preferably 2-8.
• the number of carbon atoms contained in the other amino group-bonded moiety is preferably 2-6.
• R represents an alkylene group having 2 to 8 carbon atoms
• X represents an oxygen atom or —NH
• k represents an integer of 2 or more in the case of polyetherdiamine, In the case, it represents an integer of 1 or more.
• Plural R in one molecule may be different from each other.
• a compound having a structure represented by the following formula (2) is preferred as the polyether diamine, and a compound having a structure represented by the following formula (3) is preferred as the polyalkylene polyamine.
• R 1 is an ethylene group or propylene group
• R 2 is an alkylene group having 2 to 6 carbon atoms
• R 3 is an alkylene group having 2 to 6 carbon atoms
• R 4 is an alkylene group having 2 to 8 carbon atoms
• m is 1
• n represents an integer of 1 or more
• R 1 and R 2 may be the same or different.
• R 3 and R 4 may be the same or different.
• polyether diamine represented by the formula (2) for example, polyoxypropylene diamine R 2 is a propylene group and m is 1 or more compound), polyoxyethylene diamine (Ri, R 2 is ethylene group, m is 1 or more compound), 4, 7, 10 trioxa-tridecane-1, 13 diamine (R 1 is an ethylene group, R 2 is a trimethylene group, and m is 2).
• Specific polyalkylene polyamines represented by the formula (3) include, for example, tetraethylene pentamine (a compound in which R 3 and R 4 are ethylene groups and n is 2), pentaethylenehexamine (R 3 and R 4 are Compound with ethylene group, n is 3), heptaethyleneoctamine (R 3 , R 4 is ethylene group, compound with n is 5), N, N, -bis (3-aminopropyl) -ethylenediamine (R 3 is ethylene) Group, R 4 is a trimethylene group, n is 1 compound), N, N, -bis (2 aminoethyl) -1, 4 butanediamine (R 3 is a tetramethylene group, R 4 is an ethylene group, n is 1 Compound).
• tetraethylene pentamine a compound in which R 3 and R 4 are ethylene groups and n is 2
• pentaethylenehexamine R 3 and R 4 are Compound with ethylene group, n is 3
• the concentration of the water-soluble polyamine in the abrasive is in the range of 0.001 to 20% by mass from the viewpoint of obtaining a sufficient effect of suppressing the polishing rate, and the polishing rate, the uniformity of the abrasive mixture, and the water solubility. It is preferable to set appropriately considering the polymerization average molecular weight of polyamine.
• the concentration of the water-soluble polyamine definitive during polishing agent is more preferably in the range of 0.05 to 5 mass 0/0. In the case where the surface to be polished is the surface of the diacid-silicon layer, the concentration of the water-soluble polyamine is more preferably in the range of 0.05 to 2% by mass.
• water according to the present invention is not particularly limited, effects on other agent, contamination of impurities, from the effects of the P H or the like, pure water, ultrapure water, preferably using an ion-exchange water or the like be able to.
• the present abrasive can be used in an alkaline pH region.
• pH 9-12 is preferable. If the pH is less than 9, the dispersibility may decrease.If the pH is more than 12, there is no problem in polishing characteristics, but the surface to be polished may be affected. May deteriorate.
• the abrasive according to the present invention may contain other components.
• a typical example is a dispersant.
• Dispersing agents include water-soluble organic polymers and anionic surfactants.
• a polymer having a carboxylic acid group or a carboxylic acid ammonium salt is preferred.
• the abrasive according to the present invention does not necessarily have to be supplied to the polishing site as a mixture of all the constituent abrasive materials in advance.
• abrasive materials may be mixed to form an abrasive composition.
• it may be divided into a liquid 1 containing cerium oxide particles, water, and optionally a dispersing agent, and a liquid 2 containing a water-soluble polyamine, and the mixing ratio may be adjusted appropriately during polishing. Good. This method is useful when it is necessary to adjust the polishing rate in accordance with the concentration of boron or phosphorus in the diacid-silicate material layer.
• the polishing agent is supplied to the polishing pad, and the surface to be polished of the semiconductor device and the polishing pad are brought into contact with each other by relative movement between the two.
• the surface to be polished of the diacid-based material layer is polished.
• the conditions for the diacid-based material are the same as those described in relation to the abrasive according to the present invention.
• FIG. 2 is a diagram showing an example of a polishing apparatus applicable to the polishing method of the present invention. While supplying the polishing agent 36 from the polishing agent supply pipe 35, the semiconductor device 31 is held on the polishing head 32, and the polishing surface plate 33 In this method, the polishing head 34 and the polishing surface plate 33 are rotated and brought into contact with the polishing pad 34 affixed to the surface, and are moved relative to each other.
• the polishing apparatus according to the present invention is not limited to this.
• the polishing head 32 may not only rotate but also move linearly.
• the polishing surface plate 33 and the polishing pad 34 may be as large as or smaller than the semiconductor device 31. In that case, it is preferable that the entire surface of the semiconductor device be polished by moving the polishing head 32 and the polishing platen 33 relatively.
• the polishing surface plate 33 and the polishing pad 34 may not be a rotary type but may be a belt type that moves in one direction.
• the polishing conditions of the polishing apparatus are not particularly limited, but the polishing rate can be improved by applying a load to the polishing head 32 and pressing it against the polishing pad 34.
• the polishing pressure at this time is particularly preferably about 3 to 40 kPa from the viewpoint of uniformity in semiconductor devices having a polishing rate of preferably about 0.5 to 50 kPa, flatness, and prevention of polishing defects such as scratches.
• the rotation speed of the polishing surface plate and the polishing head is preferably about 50 to 500 rpm, but is not limited thereto.
• polishing pad a general nonwoven fabric, foamed polyurethane, porous resin, non-porous resin and the like can be used.
• a groove check such as a lattice shape, a concentric circle shape, or a spiral shape is made.
• the polishing agent of the present invention it is possible to realize a highly flat surface with unevenness on the surface to be polished of the silicon dioxide-based material layer with a small amount of polishing.
• the polished surface is very flat and the remaining film thickness can be easily increased. It is also possible to reduce the cost of film formation and improve the throughput. Therefore, in the manufacture of semiconductor devices using this polishing method, the quality can be improved, the cost can be reduced, and the throughput can be improved.
• the present invention can be suitably used particularly for a semiconductor device employing ILD, STI and PMD.
• Examples 1 to 11 and 14 are examples, and examples 12 and 13 are comparative examples.
• “%” means mass% unless otherwise specified. The characteristic values were evaluated by the following methods. [0058] (pH)
• the “aggregation and precipitation time” in the examples was determined as the time required for 20 mL of an abrasive to be put into a glass test tube having a diameter of 18 mm, left to stand for 10 days, and separated into two layers to form a supernatant.
• Polishing was performed with the following apparatus and conditions.
• Polishing machine fully automatic CMP machine MIRRA (manufactured by APPLIED MATERIALS)
• Polishing pad 2-layer pad IC—1400 K-groove or single-layer pad IC—1000 K-groove (Rodel)
• Polishing pad conditioning MEC100—PH3. 5L (Mitsubishi Materials Corporation) Polishing surface plate rotation speed: 77rpm
• Polishing pressure 27.6 kPa (Example 1 to: L 1, 14 abrasive)
• Polishing pressure 13.8 kPa (Example: For abrasives 12 and 13)
• a film thickness meter UV—1280SE manufactured by KLA—Tencor was used.
• BPSG films (l / zm thickness) made by International SEMATECH with boron and phosphorus concentrations of 3.52% and 3.85%, respectively, on the silicon surface The blanket wafer which covered the whole surface was used.
• FIG. 4 shows a schematic side sectional view of the blanket wafer.
• STI864CMP000 BPSG film (boron power ⁇ 3.5 2%, phosphorus 3.85%) (: Lm thickness) and pattern width 100 m, a patterned wafer that covered the entire silicon surface with a stripe pattern groove with a pattern spacing of 10 m was used.
• the polishing agent of Example 5 was the same as the polishing agent of Examples 1 to 4 and 12 except that the boron force of the BPSG film of STI864CMP000 was 3% and phosphorus was 14%.
• This pattern is a simulated pattern of STI.
• Figure 5 shows a schematic cross-sectional side view of a patterned wafer.
• Reference numeral 51 represents a groove of the silicon wafer.
• the steps on the patterned wafer surface used in Examples 1 to 5 and 8 to 12, ie, the pattern groove depth (corresponding to L in FIG. 5) were all 350 nm.
• the present invention is limited to this value. It is not specified.
• Example 14 For the abrasive of Example 14 (the same abrasive as Example 1), with respect to the convex portion of the silicon surface of STI864CMP000 having the groove of the stripe pattern similar to the case of the abrasives of Examples 1 to 4 and 12, A patterned wafer was used in which a diacid key film (10 nm thickness) and a nitride nitride film (140 nm thickness) were sequentially coated with a diacid key film (700 nm thickness). In Example 14, the step, that is, the pattern groove depth of the patterned wafer used in Example 14 was 500 nm.
• the blanket wafer was polished for 60 seconds, and the difference in film thickness before and after polishing was taken as the polishing rate.
• the data on the convex film thickness and the concave film thickness in the density pattern of 10%, 20%, 30%, 40%, and 50% in one chip is shown in the center of each density pattern.
• One point at a time was measured before and after polishing, and these were evaluated as values at each density.
• the unevenness of the film thickness of the convex part It is the difference between the maximum value and the minimum value of the film thickness difference of the convex portion of the tee.
• the maximum polishing amount of the concave portion is the maximum value of the film thickness difference of the concave portion of each density before and after polishing.
• the maximum level difference is the largest value of the level difference between the convex part and the concave part of each density after polishing.
• An optical interference type fully automatic film thickness measuring device UV1280SE manufactured by KLA Tencor
• the density value is 10%, for example, when the pattern wafer is viewed from a direction orthogonal to the surface thereof, the convex portion corresponding to the sum of the width of the convex portion pattern and the width of the concave portion pattern is obtained. This means the ratio of the width of the pattern.
• a mixture of acid cerium bombardment and poly (ammonium acrylate) having a polymerization average molecular weight of 5000 as a dispersant is mixed with stirring in deionized water so that the mass ratio is 100: 0.7. Sonic dispersion and filtering were performed to produce a mixture with a 10% barrel concentration and 0.07% dispersant concentration. This mixture was diluted 5 times with deionized water to prepare an abrasive mixture A having an abrasive concentration of 2% and a dispersant concentration of 0.014%. The pH of the abrasive mixture A was 7.6, and the average particle size of the abrasive grains was 0.19 / zm.
• polyoxypropylenediamine having a polymerization average molecular weight of 230 (manufactured by BASF, trade name polyetheramine) is dissolved in deionized water as a water-soluble polyamine, and an additive solution B having a polyoxypropylenediamine concentration of 1.0% is obtained.
• BASF trade name polyetheramine
• Additive liquid C was prepared in the same manner as additive liquid B in Example 1, except that the concentration of polyoxypropylene diamine was 2.0%.
• the abrasive concentration was 1% and the polyacrylic acid ammonia was mixed.
• a polishing agent was prepared having a solution concentration of 0.007%, a polyoxypropylene diamine concentration of 1.0%, and a pH of 11.2.
• Additive liquid D was prepared in the same manner as liquid B.
• This additive liquid D and abrasive mixture A prepared in the same manner as in Example 1 were mixed at a mass ratio of 1: 1 while stirring to obtain an abrasive concentration of 1% and polyacrylic acid ammonia.
• a polishing agent having a concentration of 0.007%, a polyoxypropylene diamine concentration of 1.25%, and a pH of 11.3 was prepared.
• Additive liquid E was prepared in the same manner as additive liquid B in Example 1, except that the concentration of polyoxypropylene diamine was 3.0%.
• This additive liquid E and the abrasive mixture A prepared in the same manner as in Example 1 were mixed at a mass ratio of 1: 1 while stirring to obtain an abrasive concentration of 1% and polyacrylic acid ammonia.
• a polishing agent having a concentration of 0.007%, a polyoxypropylene diamine concentration of 1.5%, and a pH of 11.4 was prepared.
• Example 1 except that polyoxypropylene diamine having a polymerization average molecular weight of 400 (BASF, trade name: Polyetheramine) was used and the concentration of the polyoxypropylene diamine was adjusted to 1.0%.
• Additive liquid F was prepared in the same manner as additive liquid B. This additive liquid F and the abrasive mixture A prepared in the same manner as in Example 1 were mixed at a mass ratio of 1: 1 while stirring to obtain an abrasive concentration of 1% and polyacrylic acid ammonium.
• An abrasive having a concentration of 0.007%, a polyoxypropylene diamine concentration of 0.5%, and a pH of 10.9 was prepared.
• Additive liquid G was prepared in the same manner as additive liquid F in Example 5, except that the concentration of polyoxypropylene diamine was 2.0%.
• This additive liquid G and the abrasive mixture A prepared in the same manner as in Example 1 were mixed at a mass ratio of 1: 1 while stirring to obtain an abrasive concentration of 1% and polyacrylic acid ammonia.
• An abrasive with a 0.007% solution concentration, 1.0% polyoxypropylenediamine concentration, and 11.1 pH was prepared.
• Example 1 except that polyoxypropylene diamine having a polymerization average molecular weight of 440 (BASF, trade name: Polyetheramine) was used and the concentration of the polyoxypropylene diamine was adjusted to 1.0%.
• Additive liquid H was prepared in the same manner as additive liquid B. While stirring the additive liquid solution H and the abrasive mixture A prepared in the same manner as in Example 1 at a mass ratio of 1: 1, By mixing, an abrasive having an abrasive concentration of 1%, an ammonium polyacrylate concentration of 0.007%, a polyoxypropylene diamine concentration of 0.5%, and a pH of 10.9 was produced. .
• additive liquid I was prepared in the same manner as in preparation of additive liquid B of Example 1.
• This additive liquid I and the abrasive mixture A prepared in the same manner as in Example 1 were mixed with stirring at a mass ratio of 1: 1, so that the barrel concentration was 1% and the polyacrylic acid ammonium was mixed.
• a polishing agent was prepared with a concentration of 007%, 4, 7, 10 trioxatridecane 1,13 diamin 0.25% and pH power 0.7.
• Additive liquid J was prepared in the same manner as additive liquid I in Example 8, except that the concentration of 4, 7, 10 trioxatridecane 1,13 diamine was 0.3%.
• This additive liquid J and abrasive mixture A prepared in the same manner as in Example 1 were mixed at a mass ratio of 1: 1 while stirring to obtain an emulsion concentration of 1% and polyacrylic acid ammonia.
• a polishing agent was prepared with a volume of 0.007%, 4, 7, 10 trioxatridecane 1,13 diamin concentration of 0.15% and pH of 10.6.
• N, ⁇ '-bis (3aminopropyl) -ethylenediamine manufactured by ASF with an average molecular weight of 220
• concentration of ⁇ , ⁇ '-bis (3-aminopropyl) -ethylenediamine is 0.4%.
• an additive liquid bottle was prepared in the same manner as the additive liquid tank of Example 1.
• the concentration of the granules is 1% and the polyacrylic acid ammonia is mixed.
• An abrasive having a concentration of 0.007%, N , ⁇ '-bis (3aminopropyl) monoethylenediamine, of 0.2%, and pI " ⁇ S11.3 was prepared.
• additive liquid L was prepared.
• This additive liquid L was prepared in the same manner as in Example 1. By mixing the abrasive mixture A with stirring at a mass ratio of 1: 1, the abrasive concentration is 1%, the polyacrylic acid ammonium is 0.007%, and the pentaethylenehexamine concentration is 0.1. An abrasive with% and pH of 11.2 was prepared.
• Table 1 shows the composition of the abrasive, pH, the average particle diameter of the abrasive grains, and the coagulation sedimentation time of the abrasive
• Table 2 shows the evaluation results of the polishing characteristics.
• the polishing characteristics of Examples 6, 7, and 13 were evaluated only for a blanket wafer with a BP SG film.
• the polishing characteristics of Examples 9 and 10 were evaluated only on a wafer with a pattern of BPSG film.
• the average particle size of the abrasive grains of both the abrasive mixture A and the abrasive was 0.1. That is, the agglomeration of abrasive grains did not proceed by mixing with additive liquids B to M.
• these abrasives were allowed to stand and the dispersion stability was evaluated, even after 1 week or longer, no aggregation and precipitation occurred, and the dispersion was maintained.
• These dispersion states are the same as those in the mixture A with no additives added, and left for 10 days according to the above dispersion stability evaluation method. Even though the supernatant layer did not appear, the dispersibility was very good. However, only the abrasive of Example 13 caused precipitation due to agglomeration of barrels in a few tens of minutes.
• the concentrations of boron and phosphorus are The polishing rate (O) for the BPSG films of 3.52% and 3.85%, respectively, is 53 nm Z for the polishing agent of Example 1, 23 nmZ for the polishing agent of Example 2, and 21 nmZ for the polishing agent of Example 3.
• the abrasive of 4 it was 17 nmZ, in the case of the abrasive of Example 8, 30 nmZ, and in the case of the abrasive of Example 11, it was 15 nmZ.
• the polishing time of the patterned wafer was 120 seconds with the polishing agent of Example 1, the variation in the film thickness of the convex part was 48 nm, the maximum polishing amount of the concave part was 190 nm, and the maximum step was 3 nm.
• the polishing agent of Example 2 the polishing time of the patterned wafer was 150 seconds, the film thickness variation of the convex part was 25 nm, the maximum polishing amount of the concave part was 120 nm, and the maximum step was 1 nm.
• the polishing time of the patterned wafer was 150 seconds, the film thickness variation of the convex part was 20 nm, the maximum polishing amount of the concave part was 100 nm, and the maximum step was 5 nm.
• the polishing time of the patterned wafer was 180 seconds, the film thickness variation of the convex part was l nm, the maximum polishing amount of the concave part was 100 nm, and the maximum step was 3 nm.
• the polishing characteristics of the blanket wafers of each of the abrasives of Examples 5 and 6 were as follows.
• the polishing time for the patterned wafer was 120 seconds with the abrasive of Example 5, the film thickness variation of the convex part was 10 nm, the maximum polishing amount of the concave part was 90 nm, and the maximum step was 25 nm.
• the polishing rate (O 2) for the BPSG film having boron and phosphorus concentrations of 13% and 14%, respectively, was 3 nmZ.
• the polishing time of the patterned wafer was 180 seconds, the film thickness variation of the convex part was 7 nm, the maximum polishing amount of the concave part was 80 nm, and the maximum step was 2 nm.
• the polishing time of the patterned wafer was 150 seconds, the film thickness variation of the convex part was 26 ⁇ m, the maximum polishing amount of the concave part was 110 nm, and the maximum step was 1 nm.
• the polishing time of the patterned wafer is 180 seconds, the film thickness variation of the convex part is 19 nm, and the concave part is The maximum polishing amount was 108 nm and the maximum step was 4 nm.
• the polishing time of the patterned wafer was 210 seconds, the film thickness variation of the convex part was 17 nm, the maximum polishing amount of the concave part was 71 nm, and the maximum step was 13 nm.
• the polishing rate (O) for the blanket wafer of the BPSG film having the boron and phosphorus concentrations of 13% and 14%, respectively, of the polishing agents of Examples 12 and 13 was 595 nmZ for Example 12 and Example 13 In this case, it was 551 nmZ. Also, the polishing rate (O) for the blanket wafer of BPSG film with boron and phosphorus concentrations of 3.52% and 3.85%, respectively, is 330 nmZ for Example 12 and 306 nmZ for Example 13. Met.
• the polishing time of the patterned wafer was 60 seconds with the polishing agent of Example 12, the film thickness variation of the convex part was 93 nm, the maximum polishing amount of the concave part was 286 nm, and the maximum step was 5 nm.
• the polishing agents of Examples 1 to 11 which are examples of the present invention, compared with the polishing agents of Comparative Examples 12 and 13, and the polishing rate of the BPSG film. It can be understood that is sufficiently suppressed. Also, from the results of the polishing characteristics of the patterned wafer, the level difference was eliminated with the polishing time of 60 seconds in the polishing agent of Example 12, but the film thickness variation of the convex part was very large and the polishing amount of the concave part was large.
• Examples 1 to 5 and 8 to which are examples of the present invention With the polishing agent of L 1, the level difference is eliminated in the polishing time from 120 seconds to 210 seconds, and the film thickness variation of the convex portion is small. It can also be seen that the amount of polishing of the recesses is very small.
• the maximum level difference is slightly larger than other polishing agents, but the maximum polishing amount of the concave portion is suppressed to the smallest in Examples 1 to 5 and 8 to 11, Good results were obtained.
• BPSG film 1 Boron and phosphorus concentrations are 3.52% and 3.85%, respectively.
• BPSG film 2 Concentrations of boron and phosphorus are 13% and 14%, respectively.
• the polishability of the diacid-based silicon film was evaluated.
• the polishing time of the patterned wafer was 180 seconds
• the film thickness variation of the convex part was 33 nm
• the maximum polishing amount of the concave part was 84 nm
• the maximum step was l nm.
• Example 14 which is an example of the present invention, the steps were eliminated in the same polishing time as in Examples 1 to 5, 8 to 11 and the film thickness variation of the convex portion was small. In addition, the amount of polishing of the recesses is suppressed to a small extent. From this, it is understood that the present invention is also useful when the surface to be polished is a surface of a diacidic silicon layer.
• the present invention can be suitably used for a semiconductor device employing ILD, STI, and PMD.
• ILD inorganic semiconductor
• STI shallow trench isolation
• PMD inorganic semiconductor
• the specification of Japanese patent application 2005-092608 filed on March 28, 2005 The entire contents of the claims, drawings and abstract are hereby incorporated by reference as the disclosure of the specification of the present invention.

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• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Mechanical Treatment Of Semiconductor (AREA)
• Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

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• 2005
  • 2005-03-28 JP JP2005092608A patent/JP2006278522A/ja not_active Withdrawn
• 2006
  • 2006-02-27 KR KR1020077018571A patent/KR20070112778A/ko not_active Ceased
  • 2006-02-27 CN CN2006800094337A patent/CN101147242B/zh not_active Expired - Lifetime
  • 2006-02-27 WO PCT/JP2006/303648 patent/WO2006103858A1/ja not_active Ceased
  • 2006-02-27 EP EP06714785A patent/EP1865546A4/en not_active Withdrawn
  • 2006-03-10 TW TW095108278A patent/TW200716728A/zh unknown
• 2007
  • 2007-09-28 US US11/863,852 patent/US7695345B2/en not_active Expired - Lifetime

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