Alkaline earth metal-containing cleaning solution for cleaning semiconductor element, and method for cleaning semiconductor element using same
10377978 ยท 2019-08-13
Assignee
Inventors
Cpc classification
H01L21/02063
ELECTRICITY
G03F7/423
PHYSICS
H01L21/76814
ELECTRICITY
International classification
H01L21/02
ELECTRICITY
H01L21/311
ELECTRICITY
Abstract
According to the present invention, it is possible to provide a cleaning solution which removes a dry etching residue and photoresist on a surface of a semiconductor element having a low dielectric constant film (a low-k film) and at least one material selected from between a material that contains 10 atom % or more of titanium and a material that contains 10 atom % or more of tungsten, wherein the cleaning solution contains: 0.002-50 mass % of at least one type of oxidizing agent selected from among a peroxide, perchloric acid, and a perchlorate salt; 0.000001-5 mass % of an alkaline earth metal compound; and water.
Claims
1. A cleaning solution which removes a dry etching residue and a photoresist on a surface of a semiconductor element having a low dielectric constant film (a low-k film) and at least one material selected from a material that contains 10 atomic % or more of titanium and a material that contains 10 atomic % or more of tungsten, wherein: the cleaning solution comprises: 0.002 to 50% by mass of at least one oxidant selected from the group consisting of a peroxide, perchloric acid and a perchlorate salt, 0.000001 to 5% by mass of an alkaline earth metal compound, a pH adjuster, and water; the cleaning solution has a pH value ranging from 3 to 14; and the cleaning solution does not contain hydrogen fluoride and does not contain strontium nitrate.
2. The cleaning solution according to claim 1, wherein the pH value of the cleaning solution is 7.7 to 14.
3. The cleaning solution according to claim 1, wherein the cleaning solution includes at least one peroxide selected from the group consisting of hydrogen peroxide, urea peroxide, m-chloro peroxybenzoic acid, tert-butyl hydroperoxide, peracetic acid, di-tert-butyl peroxide, benzoyl peroxide, acetone peroxide, methyl ethyl ketone peroxide, hexamethylene triperoxide and cumene hydroperoxide.
4. The cleaning solution according to claim 1, wherein the cleaning solution comprises at least one perchlorate salt selected from the group consisting of ammonium perchlorate, potassium perchlorate, calcium perchlorate, magnesium perchlorate, silver perchlorate, sodium perchlorate, barium perchlorate, lithium perchlorate, zinc perchlorate, acetylcholine perchlorate, lead perchlorate, rubidium perchlorate, cesium perchlorate, cadmium perchlorate, iron perchlorate, aluminium perchlorate, strontium perchlorate, tetrabutylammonium perchlorate, lanthanum perchlorate, indium perchlorate and tetra-n-hexylammonium perchlorate.
5. The cleaning solution according to claim 1, wherein the oxidant is hydrogen peroxide.
6. The cleaning solution according to claim 1, wherein the pH value of the cleaning solution ranges from 8 to 14.
7. The cleaning solution according to claim 1, wherein: the cleaning solution is adapted to function as a cleaning solution that removes a dry etching residue and a photoresist on a surface of a semiconductor element having a low dielectric constant film (a low-k film) and at least one material selected from the group consisting of a material comprising 10 atomic % or more of titanium and a material comprising 10 atomic % or more of tungsten; and the at least one material comprises at least one selected from the group consisting of titanium oxide, titanium nitride, titanium and titanium silicide.
8. The cleaning solution according to claim 1, wherein: the cleaning solution is adapted to function as a cleaning solution that removes a dry etching residue and a photoresist on a surface of a semiconductor element having a low dielectric constant film (a low-k film) and at least one material selected from the group consisting of a material comprising 10 atomic % or more of titanium and a material comprising 10 atomic % or more of tungsten; and the at least one material comprises at least one selected from the group consisting of tungsten oxide, tungsten nitride, tungsten and tungsten silicide.
9. The cleaning solution according to claim 1, wherein the alkaline earth metal compound is at least one selected from the group consisting of a calcium compound, a strontium compound and a barium compound, with the proviso that the strontium compound does not include the strontium nitrate.
10. A cleaning method for removing a dry etching residue and a photoresist on a surface of a semiconductor element having a low dielectric constant film (a low-k film) and at least one material selected from the group consisting of a material comprising 10 atomic % or more of titanium and a material comprising 10 atomic % or more of tungsten, said method comprising contacting the surface with the cleaning solution of claim 1.
11. The cleaning solution according to claim 1, wherein the alkaline earth metal compound is selected from the group consisting of an alkaline earth metal acetate, an alkaline earth metal bromide, an alkaline earth metal chloride, an alkaline earth metal fluoride, an alkaline earth metal iodide, an alkaline earth metal nitrate, an alkaline earth metal oxide, an alkaline earth metal phosphate, an alkaline earth metal sulfate, and combinations thereof.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
EMBODIMENTS FOR CARRYING OUT THE INVENTION
(9) The cleaning solution of the present invention is used in the cleaning process in the production of a semiconductor element, and in this case, a dry etching residue and a photoresist can be cleaned/removed at a quite satisfactory level, and it is possible to suppress damage to at least a low-k film and at least one material selected from a titanium-containing material and a tungsten-containing material. The cleaning solution of the present invention can be used for a semiconductor element having a titanium-containing material, and can also be used for a semiconductor element having a tungsten-containing material, and further can be used for a semiconductor element having both the titanium-containing material and the tungsten-containing material. When a semiconductor element has both titanium and tungsten, the titanium and the tungsten are not required to be contained in the same layer constituting one semiconductor element, and may be respectively contained in different layers constituting one semiconductor element. According to the present invention, by using one cleaning solution, corrosion of titanium can be prevented in a layer containing the titanium, and corrosion of tungsten can be prevented in another layer containing the tungsten, and therefore it is significantly convenient. It is sufficient when the semiconductor element to which the cleaning solution of the present invention is applied includes at least one of titanium and tungsten, and a metal other than titanium and tungsten may be included therein.
(10) The titanium-containing material included in the semiconductor element to which the cleaning solution of the present invention is applied is a material containing 10 atomic % or more of titanium, and the atomic composition percentage of titanium is preferably 15 atomic % or more, more preferably 20 atomic % or more, even more preferably 25 atomic % or more, and particularly preferably 30 atomic % or more.
(11) In the present invention, the content of titanium can be examined by measuring the constituent ratio of titanium atoms in the targeted titanium-containing material according to the ion sputtering method of X-ray photoelectron spectroscopy (XPS). The vicinity of the surface of the titanium-containing material is oxidized, and therefore the constituent ratio of oxygen atoms therein may be higher than that in the inner part of the material. For this reason, the surface of the titanium-containing material is etched by ion sputtering until the constituent ratio of titanium atoms and oxygen atoms becomes constant, thereby measuring the constituent ratio of titanium atoms in the inner portion of the titanium-containing material exposed by ion sputtering. As a measurement apparatus, a fully automatic XPS analyzer K-Alpha (manufactured by Thermo Fisher Scientific Inc.) can be used.
(12) Specific examples of the titanium-containing material include titanium oxide, titanium nitride, titanium and titanium silicide, and preferred are titanium oxide, titanium nitride and titanium. However, the titanium-containing material is not limited thereto as long as it is a material containing 10 atomic % or more of titanium.
(13) The tungsten-containing material included in the semiconductor element to which the cleaning solution of the present invention is applied is a material containing 10 atomic % or more of tungsten, and the atomic composition percentage of tungsten is preferably 15 atomic % or more, more preferably 20 atomic % or more, even more preferably 25 atomic % or more, still more preferably 30 atomic % or more, particularly preferably 35 atomic % or more, and most preferably 40 atomic % or more.
(14) In the present invention, the content of tungsten can be examined by measuring the constituent ratio of tungsten atoms in the targeted tungsten-containing material according to the ion sputtering method of XPS as described above. As a measurement apparatus, a fully automatic XPS analyzer K-Alpha (manufactured by Thermo Fisher Scientific Inc.) can be used.
(15) Specific examples of the tungsten-containing material include tungsten oxide, tungsten nitride, tungsten and tungsten silicide, and preferred are tungsten oxide, tungsten nitride and tungsten. However, the tungsten-containing material is not limited thereto as long as it is a material containing 10 atomic % or more of tungsten.
(16) The semiconductor element to which the cleaning solution of the present invention is applied may include copper or a copper alloy. Specific examples of copper and the copper alloy include copper, aluminium copper, manganese copper, nickel copper, titanium copper, gold copper, silver copper, tungsten copper, copper silicide, cobalt copper and zinc copper, and preferred are copper, aluminium copper, manganese copper, nickel copper and titanium copper. However, copper and the copper alloy are not limited thereto.
(17) The concentration of the alkaline earth metal compound contained in the cleaning solution of the present invention is 0.000001 to 5% by mass, preferably 0.000005 to 1% by mass, even more preferably 0.00005 to 0.7% by mass, and particularly preferably 0.0005 to 0.5% by mass. When the concentration is within the above-described range, corrosion of at least one material selected from the titanium-containing material and the tungsten-containing material can be effectively prevented. When the concentration of the alkaline earth metal compound exceeds 5% by mass, removability of the dry etching residue may be reduced.
(18) The present inventors found for the first time that the alkaline earth metal compound contained in the cleaning solution exerts anticorrosive effects on at least one material selected from the titanium-containing material and the tungsten-containing material. The mechanism thereof has not been elucidated, but it is considered that the alkaline earth metal compound adsorbs to the surface of titanium or tungsten, thereby preventing corrosion of titanium or tungsten caused by an oxidant such as hydrogen peroxide and an alkali contained in the cleaning solution.
(19) Specific examples of the alkaline earth metal compound include a calcium compound, a strontium compound and a barium compound. More specific examples thereof include, but are not limited to, barium nitrate, barium hydroxide, barium chloride, barium acetate, barium oxide, barium bromide, barium carbonate, barium fluoride, barium iodide, barium sulfate, barium phosphate, calcium nitrate, calcium chloride, calcium acetate, calcium oxide, calcium bromide, calcium carbonate, calcium fluoride, calcium iodide, calcium sulfate, calcium phosphate, strontium nitrate, strontium chloride, strontium acetate, strontium oxide, strontium bromide, strontium carbonate, strontium fluoride, strontium iodide, strontium sulfate and strontium phosphate. Among them, barium nitrate, barium hydroxide, barium chloride, calcium nitrate and strontium chloride are more preferred, and barium nitrate, barium hydroxide, barium chloride and calcium nitrate are particularly preferred. These alkaline earth metal compounds may be used solely, or two or more of them may be used in combination.
(20) The concentration of at least one type of oxidant selected from the group consisting of a peroxide, perchloric acid and a perchlorate salt contained in the cleaning solution of the present invention is 0.002 to 50% by mass, preferably 0.01 to 30% by mass, more preferably 0.1 to 25% by mass, and particularly preferably 0.3 to 25% by mass. When the concentration is within the above-described range, the dry etching residue can be effectively removed.
(21) The peroxide to be used in the present invention is a compound having a structure of (OO) (O is an oxygen atom). Specific examples of the peroxide include, but are not limited to, hydrogen peroxide, urea peroxide, m-chloroperoxybenzoic acid, tert-butyl hydroperoxide, peracetic acid, di-tert-butyl peroxide, benzoyl peroxide, acetone peroxide, methyl ethyl ketone peroxide, hexamethylene triperoxide and cumene hydroperoxide. Among them, hydrogen peroxide, m-chloroperoxybenzoic acid and tert-butyl hydroperoxide are more preferred. These peroxides may be used solely, or two or more of them may be used in combination.
(22) An inorganic peroxide reacts with water, resulting in the generation of hydrogen peroxide in the cleaning solution, and therefore the inorganic peroxide is substantially equivalent to hydrogen peroxide. For this reason, the inorganic peroxide may be added to the cleaning solution in order to generate hydrogen peroxide therein. Specific examples of the inorganic peroxide include, but are not limited to, lithium peroxide, potassium peroxide, sodium peroxide, rubidium peroxide, cesium peroxide, beryllium peroxide, magnesium peroxide, calcium peroxide, strontium peroxide, barium peroxide, zinc peroxide, cadmium peroxide and copper peroxide.
(23) Specific examples of the perchloric acid or the perchlorate salt to be used in the present invention include, but are not limited to, perchloric acid, ammonium perchlorate, potassium perchlorate, calcium perchlorate, magnesium perchlorate, silver perchlorate, sodium perchlorate, barium perchlorate, lithium perchlorate, zinc perchlorate, acetylcholine perchlorate, lead perchlorate, rubidium perchlorate, cesium perchlorate, cadmium perchlorate, iron perchlorate, aluminium perchlorate, strontium perchlorate, tetrabutylammonium perchlorate, lanthanum perchlorate, indium perchlorate and tetra-n-hexylammonium perchlorate. Among them, ammonium perchlorate is more preferred. These substances may be used solely, or two or more of them may be used in combination.
(24) The water to be used in the present invention is preferably water from which metal ions, organic impurities, particles, etc have been removed by distillation, ion exchange treatment, filtering treatment, adsorption treatment or the like, and pure water and ultrapure water are particularly preferred. The concentration of water means the remaining portion of the cleaning solution from which agents are excluded.
(25) For the purpose of suppressing damage to the low-k film and the titanium-containing material and removing the dry etching residue on the surface of the product to be treated, the cleaning solution of the present invention can be used at a pH value of 0 to 14. The pH value is preferably 0.2 to 14, more preferably 0.6 to 13.1, even more preferably 1.5 to 12.8, and particularly preferably 2 to 12.5. When the pH value is within the above-described range, damage to the low-k film and the titanium-containing material can be suppressed, and the dry etching residue on the surface of the product to be treated can be selectively removed.
(26) For the purpose of suppressing damage to the low-k film and the tungsten-containing material and removing the dry etching residue on the surface of the product to be treated, the cleaning solution of the present invention can be used at a pH value of 0 to 14. The pH value is preferably 3 to 14, more preferably 5 to 13.1, even more preferably 7.7 to 12.8, and particularly preferably 8 to 12. When the pH value is within the above-described range, damage to the low-k film and the tungsten-containing material can be suppressed, and the dry etching residue on the surface of the product to be treated can be selectively removed.
(27) For the purpose of suppressing damage to the low-k film, the titanium-containing material, the tungsten-containing material and copper or the copper alloy and removing the dry etching residue on the surface of the product to be treated, the cleaning solution of the present invention can be used at a pH value of 3 to 14. The pH value is preferably 4 to 14, more preferably 5 to 12.8, even more preferably 7.7 to 12.8, and particularly preferably 8 to 12. When the pH value is within the above-described range, damage to the low-k film, the titanium-containing material, the tungsten-containing material and copper or the copper alloy can be suppressed, and the dry etching residue on the surface of the product to be treated can be selectively removed.
(28) The photoresist can be removed at any pH value. The pH value is preferably 7 to 14, more preferably 7.5 to 14, even more preferably 7.7 to 13.1, still more preferably 8.6 to 12.8, and particularly preferably 9 to 12.8.
(29) The cleaning solution of the present invention may contain a pH adjuster. As the pH adjuster, an inorganic acid, an organic acid, an inorganic alkali and an organic alkali can be arbitrarily used. Specific examples thereof include, but are not limited to, sulfuric acid, nitric acid, phosphoric acid, fluoric acid, hydrochloric acid, acetic acid, citric acid, formic acid, malonic acid, lactic acid, oxalic acid, potassium hydroxide, potassium acetate, potassium carbonate, potassium phosphate, sodium hydroxide, lithium hydroxide, cesium hydroxide, triethylamine, ammonia, tetramethylammonium hydroxide, ethanolamine and 1-amino-2-propanol. These pH adjusters may be used solely, or two or more of them may be used in combination.
(30) In the cleaning solution of the present invention, if desired, an additive which is conventionally used in semiconductor cleaning solutions may be blended within a range in which the purpose of the present invention is not impaired. For example, an oxidant other than the peroxide, perchloric acid and perchlorate salt, a metal anticorrosive, a water-soluble organic solvent, a fluorine compound, a reducing agent, a chelating agent, a surfactant, a defoaming agent, etc. may be added.
(31) The temperature at which the cleaning solution of the present invention is used is 10 to 85? C., preferably 20 to 70? C., and may be appropriately selected depending on etching conditions and a semiconductor element to be used.
(32) With the cleaning method of the present invention, ultrasonic may be used in combination according to need.
(33) The time for use of the cleaning solution of the present invention is 0.1 to 120 minutes, preferably 0.5 to 60 minutes, and may be appropriately selected depending on etching conditions and a semiconductor element to be used.
(34) As a rinse liquid to be used after use of the cleaning solution of the present invention, an organic solvent such as alcohol can be used, but it is sufficient to just rinse the semiconductor element with water.
(35) As a general low-k film, a hydroxysilsesquioxane (HSQ)-based or methylsilsesquioxane (MSQ)-based OCD (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.), a carbon-doped silicon oxide (SiOC)-based Black Diamond (trade name, manufactured by Applied Materials), Aurora (trade name, manufactured by ASM International), Coral (trade name, manufactured by Novellus Systems) and an inorganic Orion (trade name, manufactured by Trikon Tencnlogies) can be used, but the low-k film is not limited thereto.
(36) The semiconductor element and the display element to which the cleaning solution of the present invention is applied include: a substrate material such as silicon, amorphous silicon, polysilicon and glass; an insulating material such as silicon oxide, silicon nitride, silicon carbide and derivatives thereof; a material such as cobalt, cobalt alloy, tungsten and titanium-tungsten; a compound semiconductor such as gallium-arsenic, gallium-phosphorus, indium-phosphorus, indium-gallium-arsenic and indium-aluminium-arsenic; an oxide semiconductor such as chromium oxide; etc.
(37) The semiconductor element to which the cleaning solution of the present invention is applied may include a barrier metal and/or a barrier insulating film.
(38) As a general barrier metal, tantalum, tantalum nitride, titanium, titanium nitride, ruthenium, manganese, magnesium and oxides thereof can be used, but the barrier metal is not limited thereto.
(39) As a general barrier insulating film, silicon nitride, silicon carbide and silicon carbonitride can be used, but the barrier insulating film is not limited thereto.
EXAMPLES
(40) Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples, but the present invention is not limited by the Examples.
(41) SEM Observation:
(42) Observation of conditions before and after the cleaning/removal treatment of the semiconductor element was carried out using the below-described SEM (scanning electron microscope) apparatus (100,000 x).
(43) Measurement apparatus: ultra-high resolution field-emission scanning electron microscope SU9000 manufactured by Hitachi High-Technologies Corporation
(44) Judgment:
(45) The judgment after cleaning/removal was made after SEM observation based on the below-described criteria.
(46) I. Removal State of Dry Etching Residue
(47) E: The dry etching residue was completely removed.
(48) G: The dry etching residue was almost removed.
(49) P: The dry etching residue was insufficiently removed.
(50) E and G are regarded as acceptable.
(51) II. Damage to Titanium-Containing Material
(52) E: The titanium-containing material showed no change compared to that prior to cleaning.
(53) G: There was a slightly rough portion on the surface of the titanium-containing material.
(54) P: The titanium-containing material showed peeling or change in its shape.
(55) E and G are regarded as acceptable.
(56) III. Damage to Low-k Film
(57) E: The low-k film showed no change compared to that prior to cleaning.
(58) G: There was a slightly rough portion on the surface of the low-k film.
(59) P: There was a significantly concave portion in the low-k film.
(60) E and G are regarded as acceptable.
(61) IV. Damage to Tungsten-Containing Material
(62) E: The tungsten-containing material showed no change compared to that prior to cleaning.
(63) G: There was a slightly rough portion on the surface of the tungsten-containing material.
(64) P: There was a big hole in the tungsten-containing material.
(65) E and G are regarded as acceptable.
(66) V. Damage to Copper
(67) E: The copper showed no change compared to that prior to cleaning.
(68) G: There was a slightly rough portion on the surface of the copper.
(69) P: The copper showed change compared to that prior to cleaning.
(70) E and G are regarded as acceptable.
(71) VI. Removal State of Photoresist
(72) E: The photoresist was completely removed.
(73) G: The photoresist was almost removed.
(74) P: The photoresist was insufficiently removed.
(75) E and G are regarded as acceptable.
(76) Compositions of cleaning solutions used in Examples are shown in Table 1, and compositions of cleaning solutions used in Comparative Examples are shown in Tables 7 and 8.
(77) A semiconductor element having a wiring structure whose cross-sectional surface is as shown in any of
(78) The content of titanium was measured according to the ion sputtering method of X-ray photoelectron spectroscopy (XPS) as described above. Further, the content of tungsten was also measured according to the ion sputtering method of XPS as described above. In each case, as a measurement apparatus, a fully automatic XPS analyzer K-Alpha (manufactured by Thermo Fisher Scientific Inc.) was used.
Examples 1-22
(79) The semiconductor element shown in
Examples 23-41
(80) The semiconductor element shown in
Examples 42-59
(81) The semiconductor elements shown in
Examples 60-62
(82) The semiconductor elements shown in
Examples 63-79
(83) The semiconductor elements shown in
(84) In Examples 42-59 shown in Table 4 and Examples 63-79 shown in Table 6, damage to the barrier metal 6 and the barrier insulating film 7 was successfully suppressed.
Comparative Examples 1-18
(85) The semiconductor element shown in
(86) The semiconductor element shown in
Comparative Examples 19 and 20 (the Invention Described in Patent Document 1)
(87) The semiconductor element shown in
Comparative Examples 21 and 22 (the Invention Described in Patent Document 2)
(88) The semiconductor element shown in
Comparative Example 23 (the Invention Described in Patent Document 3)
(89) The semiconductor element shown in
Comparative Example 24 (the Invention Described in Patent Document 4)
(90) The semiconductor element shown in
Comparative Example 25 (the Invention Described in Patent Document 5)
(91) The semiconductor element shown in
Comparative Example 26 (the Invention Described in Patent Document 6)
(92) The semiconductor element shown in
Comparative Examples 27 and 28 (the Invention Described in Patent Document 7)
(93) The semiconductor element shown in
Comparative Examples 29 and 30 (the Invention Described in Patent Document 8)
(94) The semiconductor element shown in
Comparative Example 31 (the Invention Described in Patent Document 9)
(95) The semiconductor element shown in
Comparative Examples 32 and 33 (the Invention Described in Patent Document 10)
(96) The semiconductor element shown in
Comparative Example 34 (the Invention Described in Patent Document 11)
(97) The semiconductor element shown in
Comparative Example 35 (the Invention Described in Patent Document 12)
(98) The semiconductor element shown in
Comparative Example 36 (the Invention Described in Patent Document 13)
(99) The semiconductor element shown in
Comparative Example 37 (the Inventions Described in Patent Documents 14 and 15)
(100) The semiconductor element shown in
Comparative Example 38
(101) The semiconductor elements shown in
Comparative Example 39 (the Invention Described in Patent Document 16)
(102) The semiconductor elements shown in
Comparative Example 40 (the Invention Described in Patent Document 17)
(103) The semiconductor elements shown in
Comparative Example 41 (the Invention Described in Patent Document 18)
(104) The semiconductor elements shown in
Comparative Example 42 (the Invention Described in Patent Document 19)
(105) The semiconductor elements shown in
Comparative Example 43 (the Invention Described in Patent Document 20)
(106) The semiconductor elements shown in
Comparative Example 44 (the Invention Described in Patent Document 21)
(107) The semiconductor elements shown in
Comparative Example 45
(108) The semiconductor elements shown in
Comparative Example 46 (the Invention Described in Patent Document 22)
(109) The semiconductor elements shown in
Comparative Example 47
(110) The semiconductor elements shown in
Comparative Example 48 (the Invention Described in Patent Document 23)
(111) The semiconductor elements shown in
Comparative Example 49
(112) The semiconductor elements shown in
(113) TABLE-US-00001 TABLE 1 Oxidant I Alkaline earth metal compound pH adjuster Water Cleaning Concentration Concentration Concentration Concentration solution pH Type % by mass Type % by mass Type % by mass % by mass 1A 7.9 Hydrogen 30 Barium nitrate 0.1 KOH 1 68.9 peroxide 1B 13.1 Hydrogen 0.01 Barium nitrate 0.1 KOH 1 98.89 peroxide 1C 0.6 Hydrogen 6 Barium nitrate 1 Nitric acid 0.5 92.5 peroxide 1D 7.9 Hydrogen 30 Barium nitrate 0.2 KOH 1 68.8 peroxide 1E 9.8 Hydrogen 0.3 Barium nitrate 0.0005 KOH 0.01 99.6895 peroxide 1F 11.4 Hydrogen 6 Barium nitrate 0.003 KOH 4.5 89.497 peroxide 1G 9.9 Hydrogen 6 Barium nitrate 0.005 KOH 0.6 93.395 peroxide 1H 12.8 Hydrogen 0.5 Barium nitrate 0.5 KOH 1.2 97.8 peroxide 1I 11.0 Hydrogen 0.01 Barium nitrate 0.000005 KOH 0.01 99.979995 peroxide 1J 5.0 Hydrogen 6 Barium nitrate 0.1 93.9 peroxide 1K 2.0 Hydrogen 6 Barium nitrate 0.2 Sulfuric acid 0.05 93.75 peroxide 1L 1.5 Hydrogen 0.5 Barium nitrate 0.1 Phosphoric acid 1 98.4 peroxide 1M 7.7 Hydrogen 6 Barium nitrate 0.1 Ammonia 0.01 93.89 peroxide 1N 9.4 Hydrogen 6 Barium nitrate 0.005 TMAH 0.375 93.62 peroxide 1O 7.7 Hydrogen 6 Barium nitrate 0.3 Triethylamine 0.01 93.69 peroxide 1P 12.7 mCPBA 0.5 Barium nitrate 0.5 KOH 1.2 97.8 1Q 12.8 TBHP 0.5 Barium nitrate 0.5 KOH 1.2 97.8 1R 12.7 Ammonium 0.5 Barium nitrate 0.5 KOH 1.2 97.8 perchlorate 1S 9.9 Hydrogen 6 Barium hydroxide 0.0033 KOH 0.6 93.3967 peroxide 1T 9.9 Hydrogen 6 Barium chloride 0.004 KOH 0.6 93.396 peroxide 1U 9.7 Hydrogen 6 Calcium nitrate 0.02 KOH 0.6 93.38 peroxide 1V 9.8 Hydrogen 6 Strontium chloride 0.02 KOH 0.6 93.38 peroxide 1W 8.6 Hydrogen 30 Barium nitrate 0.04 KOH 3 66.96 peroxide 1X 9.9 Hydrogen 6 Barium nitrate 0.007 KOH 0.6 93.393 peroxide 1Y 9.9 Hydrogen 6 Barium nitrate 0.003 KOH 0.6 93.397 peroxide 1Z 9.3 Hydrogen 6 Barium nitrate 0.007 K.sub.2CO.sub.3 0.74 93.253 peroxide 1AA 10.8 Hydrogen 6 Barium nitrate 0.003 LiOH 3 90.997 peroxide 1AB 11.7 Hydrogen 6 Barium nitrate 0.003 NaOH 4.5 89.497 peroxide 1AC 9.9 Hydrogen 6 Barium nitrate 0.007 CsOH 1.60 92.393 peroxide 1AD 9.9 Hydrogen 6 Calcium nitrate 0.01 KOH 0.6 93.39 peroxide 1AE 9.9 Hydrogen 6 Strontium chloride 0.01 KOH 0.6 93.39 peroxide 1AF 9.9 Hydrogen 6 Barium hydroxide 0.01 KOH 0.6 93.39 peroxide 1AG 9.9 Hydrogen 6 Barium chloride 0.0024 KOH 4.5 89.4976 peroxide 1AH 9.8 Hydrogen 1 Barium nitrate 1 Ammonia 0.1 97.9 peroxide 1AI 10.7 Hydrogen 1 Barium nitrate 1 TMAH 1 97 peroxide 1AJ 5.0 Hydrogen 6 Barium nitrate 0.003 93.997 peroxide Oxidant I: peroxide or perchloric acid or perchlorate salt KOH: potassium hydroxide TMAH: tetramethylammonium hydroxide mCPBA: m-chloroperoxybenzoic acid TBHP: tert-butyl hydroperoxide K.sub.2CO.sub.3: potassium carbonate LiOH: lithium hydroxide NaOH: sodium hydroxide CsOH: cesium hydroxide
(114) TABLE-US-00002 TABLE 2 Cleaning Temperature Immersion time Removal Examples solution ? C. min state I Damage II Damage III 1 1A 60 20 E E E 2 1B 60 6 E E E 3 1C 60 10 E E E 4 1D 60 20 E E E 5 1E 70 10 E E E 6 1F 20 15 E E E 7 1G 40 60 E E E 8 1H 70 0.5 G G E 9 1I 70 10 E E E 10 1J 60 30 E E E 11 1K 60 10 E E E 12 1L 60 30 E E E 13 1M 60 30 E E E 14 1N 40 60 E E E 15 1O 70 10 E E E 16 1P 70 20 E E E 17 1Q 70 20 E E E 18 1R 70 20 E E E 19 1S 40 60 E E E 20 1T 40 60 E E E 21 1U 40 60 G E E 22 1V 40 60 E E E Removal state I: removal state of dry etching residue 3 Damage II: damage to titanium-containing material 1 Damage III: damage to low-k film 2
(115) TABLE-US-00003 TABLE 3 Cleaning Temperature Immersion time Removal Examples solution ? C. min state I Damage III Damage IV 23 1A 60 20 E E E 24 1B 60 6 E E E 25 1D 60 20 E E E 26 1E 70 10 E E E 27 1F 20 15 E E E 28 1G 40 60 E E E 29 1H 70 0.5 G E E 30 1I 70 10 E E E 31 1J 60 30 E E E 32 1M 60 30 E E E 33 1N 40 60 E E E 34 1O 70 10 E E E 35 1P 70 20 E E E 36 1Q 70 20 E E E 37 1R 70 20 E E E 38 1S 40 60 E E E 39 1T 40 60 E E E 40 1U 40 60 G E G 41 1V 40 60 E E G Removal state I: removal state of dry etching residue 3 Damage II: damage to low-k film 2 Damage IV: damage to tungsten-containing material 4
(116) TABLE-US-00004 TABLE 4 Immersion Cleaning Temperature time Removal Damage Examples solution ? C. min state I II III IV V 42 1A 60 20 E E E E G 43 1F 20 5 E E E E E 44 1H 70 0.5 G E E E E 45 1I 70 10 E E E E E 46 1W 60 6 E E E E G 47 1X 60 6 G E E E E 48 1Y 40 60 G E E E E 49 1Z 60 6 G E E E E 50 1AA 20 5 G E E E E 51 1AB 20 5 G E E E E 52 1AC 60 6 G E E G E 53 1AD 60 6 G E E E E 54 1AE 60 6 G E E E E 55 1AF 60 6 G E E G E 56 1AG 20 5 G E E E E 57 1AH 60 10 E E E E E 58 1AI 60 8 G E E E E 59 1AJ 60 30 E E E E E Removal state I: removal state of dry etching residue 3 Damage II: damage to titanium-containing material 1 Damage III: damage to low-k film 2 Damage IV: damage to tungsten-containing material 4 Damage V: damage to copper 5
(117) TABLE-US-00005 TABLE 5 Immersion Cleaning Temperature time Removal Removal Damage Examples solution ? C. min state I state VI II III IV 60 1P 70 20 E E E E E 61 1Q 70 20 E E E E E 62 1R 70 20 E E E E E Removal state I: removal state of dry etching residue 3 Removal state VI: removal state of photoresist 8 Damage II: damage to titanium-containing material 1 Damage III: damage to low-k film 2 Damage IV: damage to tungsten-containing material 4
(118) TABLE-US-00006 TABLE 6 Immersion Cleaning Temperature time Removal Removal Damage Examples solution ? C. min state I state VI II III IV V 63 1A 60 20 E E E E E G 64 1F 20 5 E E E E E E 65 1H 70 0.5 G E E E E E 66 1I 70 10 E E E E E E 67 1W 60 6 E E E E E G 68 1X 60 6 G E E E E E 69 1Y 40 60 G E E E E E 70 1Z 60 6 G E E E E E 71 1AA 20 5 G E E E E E 72 1AB 20 5 G E E E E E 73 1AC 60 6 G E E E G E 74 1AD 60 6 G E E E E E 75 1AE 60 6 G E E E E E 76 1AF 60 6 G E E E G E 77 1AG 20 5 G E E E E E 78 1AH 60 10 E E E E E E 79 1AI 60 8 G E E E E E Removal state I: removal state of dry etching residue 3 Damage II: damage to titanium-containing material 1 Damage III: damage to low-k film 2 Damage IV: damage to tungsten-containing material 4 Damage V: damage to copper 5 Removal state VI: removal state of photoresist 8
(119) TABLE-US-00007 TABLE 7 Oxidant I Alkaline earth metal compound pH adjuster Water Cleaning Concentration Concentration Concentration Concentration solution pH Type % by mass Type % by mass Type % by mass % by mass 2A 7.9 Hydrogen 30 KOH 1 69 peroxide 2B 13.1 Hydrogen 0.01 KOH 1 98.99 peroxide 2C 0.6 Hydrogen 6 Nitric acid 0.5 93.5 peroxide 2D 7.9 Hydrogen 30 KOH 1 69 peroxide 2E 9.8 Hydrogen 0.3 KOH 0.01 99.69 peroxide 2F 11.4 Hydrogen 6 KOH 4.5 89.5 peroxide 2G 9.9 Hydrogen 6 KOH 0.6 93.4 peroxide 2H 12.8 Hydrogen 0.5 KOH 1.2 98.3 peroxide 2I 11.0 Hydrogen 0.01 KOH 0.01 99.98 peroxide 2J 5 Hydrogen 6 94 peroxide 2K 2 Hydrogen 6 Sulfuric acid 0.05 93.95 peroxide 2L 1.5 Hydrogen 0.5 Phosphoric acid 1 98.5 peroxide 2M 7.7 Hydrogen 6 Ammonia 0.01 93.99 peroxide 2N 9.4 Hydrogen 6 TMAH 0.375 93.625 peroxide 2O 7.7 Hydrogen 6 Triethylamine 0.01 93.99 peroxide 2P 12.7 mCPBA 0.5 KOH 1.2 98.3 2Q 12.8 TBHP 0.5 KOH 1.2 98.3 2R 12.7 Ammonium 0.5 KOH 1.2 98.3 perchlorate Oxidant I: peroxide or perchloric acid or perchlorate salt KOH: potassium hydroxide TMAH: tetramethylammonium hydroxide mCPBA: m-chloroperoxybenzoic acid TBHP: tert-butyl hydroperoxide
(120) TABLE-US-00008 TABLE 8 Cleaning solution Composition of cleaning solution (concentration: % by mass) 2S TMAH: 12%, hydrogen peroxide: 5%, KOH: 2%, triethanolamine: 35%, water: 46% 2T NaOH: 3%, hydrogen peroxide: 2%, polypropylene glycol (number-average molecular weight: 400): 0.05%, water: 94.95% 2U hydroxylamine sulfate: 4%, TMAH: 3.8%, citric acid: 1%, 2-methylimidazole: 1%, water: 90.2% 2V hydroxylamine sulfate: 4%, TMAH: 4.7%, acetic acid: 1%, hydroxylethylmorpholine: 2%, water: 88.3% 2W hydroxylamine: 15%, monoethanolamine: 10%, DMSO: 55%, catechol: 5%, water: 15% 2X phosphoric acid: 1.35%, hydrochloric acid: 1%, TMAH: 5%, sodium lauryl diaminoethyl glycinate: 0.01%, water: 92.64% 2Y hydrogen peroxide: 5%, aminotriazole: 0.01%, water: 94.99% 2Z hydrogen peroxide: 15%, benzyltrimethylammonium hydroxide: 0.2%, Ethoquad O/12: 0.001%, water: 84.799% 2AA TEAH: 10%, NaOH: 0.02%, 2-ethyl-4-methylimidazole: 2%, DMSO: 40%, water: 47.98% 2AB hydrogen peroxide: 14%, hydrofluoric acid: 0.3%, DGME: 58.4%, vinylimidazole: 1%, water: 26.3% 2AC hydrofluoric acid: 0.3%, DGME: 60%, 2-ethyl-4-methylimidazole: 1%, water: 38.7% 2AD hydrofluoric acid: 0.1%, aminopropyltrimethoxysilane: 0.1%, benzotriazole: 0.1%, ethanol: 1%, acetic acid: 1%, water: 97.7% 2AE hydroxylamine sulfate: 2%, TMAH: 3.4%, citric acid: 2%, sorbitol: 0.5%, water: 92.1% 2AF ammonium acetate: 5%, glycine: 0.8%, ammonia: 0.18%, DMSO: 3.6%, water: 90.42% 2AG KOH: 4.5%, barium nitrate: 0.003%, water: 95.497% 2AH N,N-diethylhydroxylamine: 10%, hydroxylamine: 15%, DMSO: 50%, catechol: 10%, water: 15% 2AI monoethanolamine: 10%, N,N-diethylhydroxylamine: 10%, DGBE: 30%, sorbitol: 10%, water: 40% 2AJ KOH: 0.005%, TMAH: 10%, DGME: 50%, pyrazole: 0.1%, water: 39.895% 2AK benzotriazole: 0.1%, 1,2,4-triazole: 0.1%, ammonium fluoride: 5%, boric acid: 1%, water: 93.8% 2AL ammonium fluoride: 0.25%, gluconic acid: 0.06%, water: 99.69% 2AM butylamine: 1%, hydroxylamine sulfate: 4%, TMAH: 2.8%, citric acid: 2%, dipropylene glycol: 5%, water: 85.2% 2AN hydrogen peroxide: 6%, barium nitrate: 0.003%, water: 93.997% 2AO TMAH: 3.35%, CyDTA: 0.11%, hydrogen peroxide: 1.64%, hexafluorosilicic acid: 0.23%, water: 94.67% 2AP KOH: 0.6%, hydrogen peroxide: 6%, hexafluorosilicic acid: 0.5%, water: 92.9% 2AQ TMAH: 2%, ammonium carbonate: 5%, hydrogen peroxide: 7.5%, surfactant A: 0.5%, citric acid: 10%, water: 75% 2AR nitric acid: 0.5%, hydrogen peroxide: 6%, ammonium carbonate: 0.5%, water: 93% TMAH: tetramethylammonium hydroxide KOH: potassium hydroxide NaOH: sodium hydroxide DMSO: dimethyl sulfoxide Ethoquad O/12: [oleylbis(2-hydroxyethyl)methylammonium-bis(trifluoromethanesulfonyl)imide] (manufactured by Lion Corporation) TEAH: tetraethylammonium hydroxide DGME: diethylene glycol monomethyl ether DGBE: diethylene glycol monobutyl ether CyDTA: trans-1,2-diaminocyclohexane-N,N,N,N-tetraacetic acid monohydrate Surfactant A: substance having the below-described chemical structure: H(OCH.sub.2CH.sub.2).sub.3(OCH.sub.2CH.sub.2CH.sub.2).sub.5(OCH.sub.2CH.sub.2).sub.3H
(121) TABLE-US-00009 TABLE 9 Immersion Comparative Cleaning Temperature time Removal Removal Damage Examples solution ? C. min state I state VI II III IV V 1 2A 60 20 E P E P 2 2B 60 6 E P E P 3 2C 60 10 E P E 4 2D 60 20 E P E P 5 2E 70 10 E P E P 6 2F 20 15 E P E P 7 2G 40 60 E P E P 8 2H 70 0.5 G P E P 9 2I 70 10 E P E P 10 2J 60 30 E P E P 11 2K 60 10 E P E 12 2L 60 30 E P E 13 2M 60 30 E P E P 14 2N 40 60 E P E P 15 2O 70 10 E P E P 16 2P 70 20 E P E P 17 2Q 70 20 E P E P 18 2R 70 20 E P E P 19 2S 50 40 E P E 20 50 20 P P E 21 2T 50 40 E P E 22 50 20 P P E 23 2U 70 30 P E P 24 2V 70 10 P E P 25 2W 65 20 P E P 26 2X 60 6 P P E 27 2Y 25 30 E E P 28 25 5 P E P 29 2Z 40 10 P E P 30 40 30 E E P 31 2AA 50 40 P P E 32 2AB 60 10 P P P 33 60 30 E P P 34 2AC 60 10 P P E 35 2AD 60 10 P P E 36 2AE 50 10 P E P 37 2AF 70 30 P P E 38 2AG 20 5 P E P E E 39 2AH 70 10 P P P E P 40 2AI 40 5 P E P E E 41 2AJ 50 20 P E P G E 42 2AK 50 6 P E P E G 43 2AL 25 1 P E P E E 44 2AM 70 15 P E P E P 45 2AN 20 5 G P E E E G 46 2AO 40 0.5 P G P P P 47 2AP 40 60 E P P P E 48 2AQ 50 3 P P E P P 49 2AR 60 10 E P E P E Removal state I: removal state of dry etching residue 3 Damage II: damage to titanium-containing material 1 Damage III: damage to low-k film 2 Damage IV: damage to tungsten-containing material 4 Damage V: damage to copper 5 Removal state VI: removal state of photoresist 8 pH of 2AN: 5 pH of 2AR: 6.3 : not carried out
INDUSTRIAL APPLICABILITY
(122) When using the cleaning solution and the cleaning method of the present invention, in the process for manufacturing the semiconductor element, damage to at least the low-k film and at least one material selected from the titanium-containing material and the tungsten-containing material can be suppressed, the photoresist and the dry etching residue on the surface of the product to be treated can be removed, the semiconductor element having high precision and high quality can be produced with a high yield, and therefore these are industrially useful.
EXPLANATIONS OF LETTERS OR NUMERALS
(123) 1: titanium-containing material 2: interlayer dielectric film (low-k film) 3: dry etching residue 4: tungsten-containing material 5: copper 6: barrier metal 7: barrier insulating film 8: photoresist