Method for depositing a film

Abstract

The present invention discloses an atomic layer deposition method for depositing a film into surface features of a substrate. The method may include the step of placing a substrate having surface features into a reactor. An organic passivator may be introduced into the reactor, which may react with a portion of the exposed hydroxyl groups within the surface features. Subsequently, the unreacted organic passivator may be purged, and then a precursor may be introduced. The precursor may react with the remaining exposed hydroxyl groups that have not interacted with the organic passivator. Subsequently, the unreacted precursor may be purged, and an oxygen source or a nitrogen source may be introduced into the reactor to form a film within the surface features.

Description

[0001] Cross-reference to related applications

[0002] This patent application claims the priority of U.S. Provisional Patent Application No. 62 / 954,053, filed on December 27, 2019. Technical Field

[0003] Generally, the present invention relates to a method for depositing a film, and more particularly, to an atomic layer deposition method for depositing a film into surface features of a substrate. Background Art

[0004] Atomic layer deposition is a chemical method for depositing thin films on a substrate. In many cases, the substrate undergoing the atomic layer deposition process includes one or more of the following high aspect ratio surface features formed therein: holes, trenches, shallow trench isolation, vias, reentrant features, etc. These high aspect ratio features typically include an opening, a top region, and a bottom region, and the film formed therein should have a low porosity.

[0005] In conventional atomic layer deposition, the opening of the surface feature narrows as film growth occurs during gap-fill. Eventually, the narrowing of the opening prevents reactants from moving to the lower part of the surface feature, including both the top region and the bottom region. This limitation prevents further film growth within the surface feature, resulting in the formation of a film with a porosity greater than desired within the surface feature.

[0006] U.S. Patent Application Publication No. 2019 / 0203354 A1 discloses a method and system for conformal adjustment of metal oxide films using chemical inhibition in atomic layer deposition. Precursors that inhibit the deposition of metal oxides may include chelating agents, such as diketones.

[0007] U.S. Patent Nos. 10,199,212 and 10,043,656 teach methods and apparatuses for selectively depositing silicon- or metal-containing dielectric materials on silicon or metal surfaces that are selective to silicon oxide or silicon nitride materials. Acetyl chloride is used as a capping agent.

[0008] Accordingly, the present invention aims to overcome one or more of the above problems and / or other problems associated with known atomic layer deposition methods. Summary of the Invention

[0009] According to one aspect of the present invention, an atomic layer deposition method for depositing a film into surface features of a substrate is disclosed. The method may include placing a substrate having surface features into a reactor, and the surface features may include exposed hydroxyl radicals. The reactor may be heated to one or more temperatures from ambient temperature to about 700 °C and optionally maintained at a pressure of 100 Torr or less. Subsequently, an organic passivator may be introduced into the reactor, and it may react with a part of the exposed hydroxyl radicals of the surface features.

[0010] Then the reactor may be purged of unreacted organic passivator using an inert gas, and subsequently a precursor gas having at least one organic amino group may be introduced to react with the unreacted hydroxyl radicals of the surface features. After that, an inert gas may be introduced into the reactor to purge unreacted precursor, and then an oxygen source or a nitrogen source may be introduced to form a film in the surface features. Finally, the reactor may be purged of unreacted oxygen source or nitrogen source and any by-products using an inert gas. The steps of introducing the organic passivator from the surface features to purging the reactor of unreacted oxygen source or nitrogen source and by-products using an inert gas may be repeated until the surface features are filled from bottom to top.

[0011] Generally, the organic passivator may be selected from acetals, ketals, orthoesters, and orthocarbonates. More specifically, the organic passivator is selected from the following formulas:

[0012] I. An acetal or ketal having the formula R 1 R 2 C(OR 3 ) 2 ,

[0013] II. An orthoester having the formula R 1 C(OR 3 ) 3 , and

[0014] III. An orthocarbonate having the formula C(OR 3 ) 4 ,

[0015] wherein R 1 is selected from hydrogen, C 1 -C 10 linear or branched alkyl, oxygen- or nitrogen-containing C 3 -C 10 linear or branched alkyl, C 3 -C 10 linear or branched cyclic alkyl, C 2 -C 10 alkenyl, C 2 -C 10 alkynyl, and C 3 -C10 Aromatic hydrocarbon, R 2 and R 3 are independently selected from C 1 -C 10 linear or branched alkyl, C-containing oxygen or nitrogen 3 -C 10 linear or branched alkyl, C 3 -C 10 linear or branched cyclic alkyl, C 2 -C 10 alkenyl, C 2 -C 10 alkynyl and C 3 -C 10 aromatic hydrocarbon.

[0016] In an exemplary embodiment, the organic passivator is at least one compound selected from: tetramethyl orthocarbonate, tetraethyl orthocarbonate, tetra-n-propyl orthocarbonate, trimethyl orthoacetate, triethyl orthoacetate, 1,1,1-triethoxypentane, 1,1,1-triethoxyheptane, triethyl orthobenzoate, 2,2-diethoxypropane, 1,1-diethoxy-1-phenylethane, 4,4-diethoxyheptane, 4,4-diethoxynonane, trimethyl orthoformate, trimethyl orthoformate and tri-n-propyl orthoformate.

[0017] The precursor may be selected from organoaminosilanes, organodiaminosilanes, organotrimethylsilylamines, organoaminosiloxanes, organocyclosiloxanes, and organoaminotitanium, organoaminohafnium, organoaminozirconium, organoaminotantalum, organoaminotungsten, organoam inomolybdenum, organoaminoaluminum, alkylaluminum, and metal alkoxides. In addition, the oxygen source is selected from oxygen, oxygen plasma, steam plasma, a mixture of water and organic amine, hydrogen peroxide, nitrous oxide, ozone, carbon dioxide plasma, carbon monoxide plasma, and combinations thereof. And the nitrogen source may be selected from ammonia, hydrazine, methylhydrazine, 1,1-dimethylhydrazine, N 2 plasma, ammonia plasma, hydrogen / nitrogen plasma, and combinations thereof.

[0018] The surface features of the present invention may have a depth-to-width aspect ratio of at least 2:1 or higher, or even at least 4:1. In some cases, the surface features have a width of 100 nm or less, may be vias, may be trenches, or a combination of vias and trenches.

[0019] In one embodiment, each time after the step of introducing the organic passivator from the surface features to purging the unreacted oxygen source or nitrogen source and by-products in the reactor with an inert gas, the thickness of the resulting film is thicker towards the bottom of the surface features than towards the top of the surface features. Detailed Description

[0020] This disclosure describes compositions and methods related to filling surface features (such as vias or trenches) with silicon- or metal-oxide-containing films in an atomic layer deposition (ALD) process or in an ALD-like process (such as, but not limited to, cyclic chemical vapor deposition). According to an exemplary embodiment, a silicon-free passivating agent reacts with the hydroxyl groups exposed on the substrate surface features, thereby creating "occupied" reactive sites on the surface features. The occupation of the reactive sites then prevents the reaction of the organoaminosilane with the occupied reactive sites, thus preventing film growth on certain regions of the surface features. The dosage of the passivating agent is controlled to limit the diffusion of the passivating agent into the lower regions of the surface features. Thus, the upper surface of the substrate and the upper portions of the surface features will be more passivated than the bottom of the trench structure, which in turn confers lower film growth near the upper surface of the substrate and the upper portions of the surface features and higher film growth near the bottom of the substrate features. This method of restricting film growth near the upper surface of the substrate and the upper portions of the surface features maintains the openings for the precursors and the oxygen source to enter the lower spaces of the surface features and completely fill these spaces with the film of interest.

[0021] When no passivating agent is used during film growth, such as in a conventional ALD conformal film growth method, film growth occurs during gap filling and the openings in the surface features narrow. Eventually, this narrowing blocks the channels to the lower portions of the surface features and, in turn, prevents further film growth within the trenches, resulting in porosity within the surface features. A similar defect phenomenon is also observed when the passivating agent diffuses to the bottom of the trenches, resulting in conformal film growth during trench filling.

[0022] A method described according to an exemplary embodiment includes:

[0023] a) placing one or more substrates having high aspect ratio surface features (with hydroxyl groups on their surfaces) into a reactor;

[0024] b) heating the reactor to one or more temperatures from ambient temperature to about 700 °C and optionally maintaining the reactor at a pressure of 100 Torr or less;

[0025] c) introducing at least one organic passivating agent into the reactor to react with those hydroxyl groups on the top surface region of the features;

[0026] d) purging the unreacted organic passivating agent with an inert gas;

[0027] e) introducing a vapor of a deposition precursor having at least one organic amine to react with those unreacted hydroxyl groups;

[0028] f) purging the unreacted precursor with an inert gas;

[0029] g) introducing an oxygen source precursor; and

[0030] h) Inert gas purge,

[0031] wherein steps c to h are repeated until the feature is filled from bottom to top.

[0032] Another method described according to an exemplary embodiment includes:

[0033] a) Introduce a silicon substrate with a suitable morphology into the deposition chamber;

[0034] b) Heat the reactor to one or more temperatures from ambient temperature to about 700 °C, and optionally maintain the reactor at a pressure of 100 Torr or less;

[0035] c) Introduce at least one organic passivating agent into the reactor to react with those hydroxyl groups on the top surface region of the feature;

[0036] d) Use inert gas to purge unreacted organic passivating agent;

[0037] e) Introduce the vapor of a deposition precursor having at least one organic amino or halo group to react with those unpassivated surfaces;

[0038] f) Use inert gas to purge unreacted precursor;

[0039] g) Introduce a nitrogen source precursor; and

[0040] h) Use inert gas purge.

[0041] The organic passivating agent described in the present invention is selected from the following formulas:

[0042] I. An acetal or ketal having the formula R 1 R 2 C(OR 3 ) 2 ;

[0043] II. An orthoester having the formula R 1 C(OR 3 ) 3 ; and

[0044] III. A orthocarbonate having the formula C(OR 3 ) 4 ;

[0045] wherein R 1 is selected from hydrogen, C 1 -C 10 linear or branched alkyl, oxygen- or nitrogen-containing C 3 -C 10 linear or branched alkyl, C 3 -C 10Linear or branched cyclic alkyl, C 2 -C 10 alkenyl, C 2 -C 10 alkynyl and C 3 -C 10 aromatic hydrocarbons. R 2 and R 3 are independently selected from C 1 -C 10 linear or branched alkyl, oxygen- or nitrogen-containing C 3 -C 10 linear or branched alkyl, C 3 -C 10 linear or branched cyclic alkyl, C 2 -C 10 alkenyl, C 2 -C 10 alkynyl and C 3 -C 10 aromatic hydrocarbons.

[0046] In one or more of the above embodiments, the oxygen source is selected from oxygen, oxygen plasma, water vapor plasma, a mixture of water and organic amine, hydrogen peroxide, nitrous oxide, ozone, carbon dioxide plasma, carbon monoxide plasma, and combinations thereof.

[0047] In one or more of the above embodiments, the nitrogen source includes, but is not limited to, ammonia, hydrazine, methyl hydrazine, 1,1-dimethyl hydrazine, N 2 plasma, ammonia plasma, hydrogen / nitrogen plasma, and combinations thereof.

[0048] Without being bound by theory, it is believed that in step c, an organic passivating agent is introduced by finely controlling the chamber pressure or the pulse time or the vapor flux of the organic passivating agent or the size of the R 1-3 groups in Formulas I to III to react mainly with those hydroxyl groups on the top surface region of the feature, thereby allowing the deposition precursor having at least one organic amino group to react with those unreacted hydroxyl groups on the bottom of the feature in step e to anchor the silicon- or metal-containing fragment. As a result, bottom-up deposition of a silicon- or metal-containing oxide film can be achieved because step g regenerates those hydroxyl groups on the top surface region of the feature by oxidizing away the organic passivation layer while forming the silicon- or metal-containing oxide film on the bottom of the feature.

[0049] Some exemplary organic passivating agents that can be used in the methods described herein are described in Table 1 below.

[0050] Table 1. Exemplary passivators

[0051]

[0052]

[0053] Deposition precursors of silicon oxide, silicon nitride, metal nitride or metal oxide having at least one organic amino or halogen group may be selected from organic aminosilanes, organic amino disilanes, organic amino trimethylsilylamines, organic amino siloxanes, organic amino cyclosiloxanes, organic amino titanium, organic amino hafnium, organic amino zirconium, organic amino tantalum, organic amino tungsten, organic amino molybdenum, organic amino aluminum, alkyl aluminums, metal alkoxides, and any other silicon- or metal-containing precursors that can be used for depositing silicon oxide, carbon-doped silicon oxide and metal oxides.

[0054] Examples of organic aminosilanes include, but are not limited to, diisopropylaminosilane, di-sec-butylaminosilane, bis(diethylamino)silane, bis(dimethylamino)silane, bis(ethylmethylamino)silane, bis(tert-butylamino)silane, diisopropylaminomethylsilane, di-sec-butylaminomethylsilane, dimethyldimethylaminosilane, dimethyltrimethylaminosilane, bis(dimethylamino)methylsilane, tetra(dimethylamino)silane, tris(dimethylamino)silane, isopropylaminotrimethylsilane, tert-butylaminotrimethylsilane, isobutylaminotrimethylsilane, cyclohexylaminotrimethylsilane, pyrrolidinyltrimethylsilane, 2-methylpyrrolidinyltrimethylsilane, 2,5-dimethylpyrrolidinyltrimethylsilane, piperidinyltrimethylsilane, 2,6-dimethylpiperidinyltrimethylsilane, 1-methylpiperazinyltrimethylsilane, pyrrolyltrimethylsilane, 2,5-dimethylpyrrolyltrimethylsilane, and imidazolyltrimethylsilane.

[0055] Examples of organic amino disilanes include, but are not limited to, diisopropylamino disilane and di-sec-butylamino disilane.

[0056] Examples of organic amino trimethylsilylamines include, but are not limited to, diisopropylaminotrimethylsilylamine, diethylaminotrimethylsilylamine, isopropylaminotrimethylsilylamine, and cyclohexylmethylaminotrimethylsilylamine.

[0057] Examples of organic amino siloxanes include, but are not limited to, 1-dimethylamino-pentamethyldisiloxane, 1-diethylamino-pentamethyldisiloxane, 1-ethylmethylamino-pentamethyldisiloxane, 1,3-bis(dimethylamino)tetramethyldisiloxane, 1-dimethylamino-heptamethyltrisiloxane, and 1,5-bis(dimethylamino)hexamethyltrisiloxane.

[0058] Examples of organoaminosiloxanes include, but are not limited to, 2-dimethylamino-2,4,4,6,6-pentamethylcyclotrisiloxane, 2-diethylamino-2,4,4,6,6-pentamethylcyclotrisiloxane, 2-ethylmethylamino-2,4,4,6,6-pentamethylcyclotrisiloxane, 2-isopropylamino-2,4,4,6,6-pentamethylcyclotrisiloxane, 2-dimethylamino-2,4,4,6,6,8,8-heptamethylcyclotetrasiloxane, 2-diethylamino-2,4,4,6,6,8,8-heptamethylcyclotetrasiloxane, 2-ethylmethylamino-2,4,4,6,6,8,8-heptamethylcyclotetrasiloxane, 2-isopropylamino-2,4,4,6,6,8,8-heptamethylcyclotetrasiloxane, 2-dimethylamino-2,4,6-trimethylcyclotrisiloxane, 2-diethylamino-2,4,6-trimethylcyclotrisiloxane, 2-ethylmethylamino-2,4,6-trimethylcyclotrisiloxane, 2-isopropylamino-2,4,6-trimethylcyclotrisiloxane, 2-dimethylamino-2,4,6,8-tetramethylcyclotetrasiloxane, 2-diethylamino-2,4,6,8-tetramethylcyclotetrasiloxane, 2-ethylmethylamino-2,4,6,8-tetramethylcyclotetrasiloxane, 2-isopropylamino-2,4,6,8-tetramethylcyclotetrasiloxane, 2-pyrrolidino-2,4,6,8-tetramethylcyclotetrasiloxane, and 2-cyclohexylmethylamino-2,4,6,8-tetramethylcyclotetrasiloxane.

[0059] Examples of organoaminotitaniums include, but are not limited to, tetra(dimethylamino)titanium, tetra(diethylamino)titanium, and tetra(ethylmethylamino)titanium.

[0060] Examples of organoaminohafniums include, but are not limited to, tetra(dimethylamino)hafnium (TDMAH), tetra(diethylamino)hafnium (TDEAH), tetra(ethylmethylamino)hafnium (TEMAH), cyclopentadienyltris(dimethylamino)hafnium (CpHf(NMe 2 ) 3 ), methylcyclopentadienyltris(dimethylamino)hafnium (MeCpHf(NMe 2 ) 3 ), ethylcyclopentadienyltris(dimethylamino)hafnium (EtCpHf(NMe 2 ) 3 ), cyclopentadienyltris(dimethylamino)hafnium (CpHf(NMeEt) 3 ), methylcyclopentadienyltris(dimethylamino)hafnium (MeCpHf(NMeEt) 3 ), ethylcyclopentadienyltris(dimethylamino)hafnium (EtCpHf(NMeEt) 3 ), cyclopentadienyltris(dimethylamino)hafnium (CpHf(NEt 2 )3 ) Methylcyclopentadienyltris(dimethylamino)hafnium (MeCpHf(NEt 2 ) 3 ) Ethylcyclopentadienyltris(dimethylamino)hafnium (EtCpHf(NEt 2 ) 3 ) Bis(cyclopentadienyl)bis(dimethylamino)hafnium (Cp 2 Hf(NMe 2 ) 2 ) Bis(methylcyclopentadienyl)bis(dimethylamino)hafnium ((MeCp) 2 Hf(NMe 2 ) 2 ) Bis(ethylcyclopentadienyl)bis(dimethylamino)hafnium ((EtCp) 2 Hf(NMe 2 ) 2 ) Bis(cyclopentadienyl)bis(dimethylamino)hafnium (Cp 2 Hf(NMeEt) 2 ) Bis(methylcyclopentadienyl)bis(dimethylamino)hafnium ((MeCp) 2 Hf(NMeEt) 2 ) Bis(ethylcyclopentadienyl)bis(dimethylamino)hafnium ((EtCp) 2 Hf(NMeEt) 2 ) Bis(cyclopentadienyl)bis(dimethylamino)hafnium ((Cp 2 Hf(NEt 2 ) 2 ) Bis(methylcyclopentadienyl)bis(dimethylamino)hafnium ((MeCp) 2 Hf(NEt 2 ) 3 ) Bis(ethylcyclopentadienyl)bis(dimethylamino)hafnium ((EtCp) 2 Hf(NEt 2 ) 2 ) (N-Methyl-2,4-cyclopentadien-1-ethylamino]bis(dimethylamino)hafnium, (N-Ethyl-2,4-cyclopentadien-1-ethylamino]bis(dimethylamino)hafnium, (N-Methyl-2,4-cyclopentadien-1-ethylamino]bis(diethylamino)hafnium, (N-Ethyl-2,4-cyclopentadien-1-ethylamino]bis(diethylamino)hafnium, (N-Methyl-2,4-cyclopentadien-1-ethylamino]bis(ethylmethylamino)hafnium, (N-Ethyl-2,4-cyclopentadien-1-ethylamino]hafnium and bis(ethylmethylamino)hafnium.

[0061] Examples of organoaminozirconiums include, but are not limited to, tetrakis(dimethylamino)zirconium (TDMAZ), tetrakis(diethylamino)zirconium (TDEAZ), tetrakis(ethylmethylamino)zirconium (TEMAZ), cyclopentadienyltris(dimethylamino)zirconium (CpZr(NMe 2 )) 3 ), methylcyclopentadienyltris(dimethylamino)zirconium (MeCpZr(NMe 2 )) 3 ), ethylcyclopentadienyltris(dimethylamino)zirconium (EtCpZr(NMe 2 )) 3 ), cyclopentadienyltris(dimethylamino)zirconium (CpZr(NMeEt) 3 ), methylcyclopentadienyltris(dimethylamino)zirconium (MeCpZr(NMeEt) 3 ), ethylcyclopentadienyltris(dimethylamino)zirconium (EtCpZr(NMeEt) 3 ), cyclopentadienyltris(dimethylamino)zirconium (CpHf(NEt 2 )) 3 ), methylcyclopentadienyltris(dimethylamino)zirconium (MeCpZr(NEt 2 )) 3 ), ethylcyclopentadienyltris(dimethylamino)zirconium (EtCpZr(NEt 2 )) 3 ), bis(cyclopentadienyl)bis(dimethylamino)zirconium (Cp 2 Zr(NMe 2 )) 2 ), bis(methylcyclopentadienyl)bis(dimethylamino)zirconium ((MeCp) 2 Zr(NMe 2 )) 2 ), bis(ethylcyclopentadienyl)bis(dimethylamino)zirconium ((EtCp) 2 Zr(NMe 2 )) 2 ), bis(cyclopentadienyl)bis(dimethylamino)zirconium (Cp 2 Zr(NMeEt) 2 ), bis(methylcyclopentadienyl)bis(dimethylamino)zirconium ((MeCp) 2 Zr(NMeEt) 2 ), bis(ethylcyclopentadienyl)bis(dimethylamino)zirconium ((EtCp) 2 Zr(NMeEt) 2 ), bis(cyclopentadienyl)bis(dimethylamino)zirconium ((Cp 2 Zr(NEt 2 )) 2) Bis(cyclopentadienyl)bis(dimethylamino)zirconium ((MeCp) 2 Zr(NEt 2 ) 3 ) Bis(ethylcyclopentadienyl)bis(dimethylamino)zirconium ((EtCp) 2 Zr(NEt 2 ) 2 ) (N-Methyl-2,4-cyclopentadien-1-yl-ethylamino]bis(dimethylamino)zirconium, (N-ethyl-2,4-cyclopentadien-1-yl-ethylamino]bis(dimethylamino)zirconium, (N-methyl-2,4-cyclopentadien-1-yl-ethylamino]bis(diethylamino)zirconium, (N-ethyl-2,4-cyclopentadien-1-yl-ethylamino]bis(diethylamino)zirconium, (N-methyl-2,4-cyclopentadien-1-yl-ethylamino]bis(ethylmethylamino)zirconium, and (N-ethyl-2,4-cyclopentadien-1-yl-ethylamino]bis(ethylmethylamino)zirconium.

[0062] Examples of organoaminotantalum include, but are not limited to, (tert-butylimino)tris(dimethylamino)tantalum, (tert-butylimino)tris(diethylamino)tantalum, and (tert-butylimino)tris(ethylmethylamino)tantalum.

[0063] Examples of organoaminotungsten include, but are not limited to, bis(tert-butylimino)bis(dimethylamino)tungsten, bis(tert-butylimino)bis(diethylamino)tungsten, and bis(tert-butylimino)bis(ethylmethylamino)tungsten.

[0064] Examples of organoaminomolybdenum include, but are not limited to, bis(tert-butylimino)bis(dimethylamino)molybdenum, bis(tert-butylimino)bis(diethylamino)molybdenum, and bis(tert-butylimino)bis(ethylmethylamino)molybdenum.

[0065] Examples of organoaminoaluminum include, but are not limited to, tris(dimethylamino)aluminum, tris(diethylamino)aluminum, and tris(ethylmethylamino)aluminum.

[0066] Examples of alkylaluminum include, but are not limited to, trimethylaluminum and triethylaluminum.

[0067] Examples of metal oxides include, but are not limited to, titanium isopropoxide, titanium methoxide, titanium ethoxide, and aluminum isopropoxide.

[0068] Examples of haloalkanes include: trichlorosilane, dichlorosilane, monochlorosilane, hexachlorodisilane, N-methyl-1,1,1,3,3,3-hexachlorodisilazane, silicon tetrachloride, 1-chloro-1,3-disilacyclobutane, 1-bromo-1,3-disilacyclobutane, 1,3-dichloro-1,3-disilacyclobutane, 1,3-dibromo-1,3-disilacyclobutane, 1,1,3-trichloro-1,3-disilacyclobutane, 1,1,3-tribromo-1,3-disilacyclobutane, 1,1,3,3-tetrachloro-1,3-disilacyclobutane, 1,1,3,3-tetrabromo-1,3-disilacyclobutane, 1,3-dichloro-1,3-dimethyl-1,3-disilacyclobutane, 1,3-bromo-1,3-dimethyl-1,3-disilacyclobutane, 1,1,1,3,3,5,5,5-octachloro-1,3,5-trisilapentane, 1,1,3,3,5,5-hexachloro-1,5-dimethyl-1,3,5-trisilapentane, 1,1,1,5,5,5-hexachloro-3,3-dimethyl-1,3,5-trisilapentane, 1,1,3,5,5-pentachloro-1,3,5-trimethyl-1,3,5-trisilapentane, 1,1,1,5,5,5-hexachloro-1,3,5-trisilapentane, 1,1,5,5-tetrachloro-1,3,5-trisilapentane, 1-iodo-1,3-disilacyclobutane, 1,1-diiodo-1,3-disilacyclobutane, 1,3-diiodo-1,3-disilacyclobutane, 1,1,3-triiodo-1,3-disilacyclobutane, 1,1,3,3-tetraiodo-1,3-disilacyclobutane and 1,3-diiodo-1,3-dimethyl-1,3-disilacyclobutane, 1,1,1,4,4,4-hexachloro-1,4-disilabutane, 1,1,1,4,4,4-hexachloro-2-methyl-1,4-disilabutane, 2,2,5,5,5-pentachloro-2,5-disilapentane, 2,2,5,5,5-pentachloro-3-methyl-2,5-disilapentane, 2,2,5,5-tetrachloro-2,5-disilahexane, 2,2,5,5-tetrachloro-3-methyl-2,5-disilahexane;1,1,1,5,5,5 - hexachloro - 1,5 - disilapentane, 2,2,6,6 - tetrachloro - 3 - methyl - 2,6 - disilaheptane, 1,1,4,4 - tetrachloro - 1,4 - disilapentane, 1,1,4,4 - tetrachloro - 2 - methyl - 1,4 - disilapentane, 1,1,4,4,4 - pentachloro - 1,4 - disilabutane, 1,1,4,4,4 - pentachloro - 2 - methyl - 1,4 - disilabutane, 1,4,4,4 - tetrachloro - 1,4 - disilabutane, 1,4,4,4 - tetrachloro - 2 - methyl - 1,4 - disilabutane, 1,4,4 - trichloro - 1,4 - disilapentane, 1,4,4 - trichloro - 2 - methyl - 1,4 - disilapentane, 1,1,5,5,5 - pentachloro - 1,5 - disilapentane, 1,1,5,5,5 - pentachloro - 2 - methyl - 1,5 - disilapentane, 1,1,5,5 - tetrachloro - 1,5 - disilahexane, 1,1,5,5 - tetrachloro - 2 - methyl - 1,5 - disilahexane, 1,5,5,5 - tetrachloro - 1,5 - disilapentane, 1,5,5,5 - tetrachloro - 2 - methyl - 1,5 - disilapentane, 1,5,5 - trichloro - 1,5 - disilahexane and 1,5,5 - trichloro - 2 - methyl - 2,6 - disilahexane, 1,1,1,3,3,3 - hexachloro - 1,3 - disilapropane, 1,1,1,3,3,3 - hexachloro - 2 - methyl - 1,3 - disilapropane, 1,1,1,3,3,3 - hexachloro - 2,2 - dimethyl - 1,3 - disilapropane and 1,1,1,3,3,3 - hexachloro - 2 - ethyl - 1,3 - disilapropane.;

[0069] The substrate includes surface features. As used herein, the term "surface feature" or "feature" means a substrate or a portion of a substrate fabricated to include one or more of the following: holes, trenches, shallow trench isolation (STI), vias, recessed features, etc. In one particular embodiment, the surface feature has a width of 100 μm or less, 1 μm or less, or 0.5 μm or less, or 50 nm or less. In this or other embodiments, the aspect ratio (depth to width ratio) of the surface feature (if present) is 2:1 or greater, or 3:1 or greater, or 4:1 or greater, or 10:1 or greater, or 20:1 or greater, or 40:1 or greater. The high aspect ratio means 2:1 or greater when the width is 100 nm or less, preferably 3:1 or greater when the width is 100 nm or less, and most preferably 4:1 or greater when the width is 100 nm or less. The trench material can be selected from Si, SiO 2 , SiN x , carbon - doped silicon oxide, or a combination thereof.

[0070] In the above formula and throughout the specification, the term "linear alkyl" refers to a linear functional group having 1 - 10, 3 - 10 or 1 - 6 carbon atoms. In the above formula and throughout the specification, the term "branched alkyl" refers to a linear functional group having 3 - 10 or 1 - 6 carbon atoms. Exemplary linear alkyls include, but are not limited to, methyl, ethyl, propyl, butyl, pentyl, and hexyl. Exemplary branched alkyls include, but are not limited to, isopropyl, isobutyl, sec - butyl, tert - butyl, isopentyl, tert - pentyl, isohexyl, and neohexyl. In certain embodiments, the alkyl may have one or more functional groups attached thereto, such as, but not limited to, alkoxy, dialkylamino, or combinations thereof. In other embodiments, the alkyl does not have one or more functional groups attached thereto. The alkyl may be saturated or unsaturated.

[0071] As previously described, the methods described herein can be used to deposit silicon oxide or metal oxide into surface features including vias and / or trenches on at least a portion of a substrate. Examples of suitable substrates include, but are not limited to, silicon, SiO 2 , titanium nitride, tungsten nitride, tantalum nitride, vanadium nitride, metals such as germanium, copper, titanium, tungsten, cobalt, ruthenium, platinum, palladium, aluminum, and combinations thereof.

[0072] The film is compatible with a variety of subsequent processing steps, such as chemical mechanical planarization (CMP) and anisotropic etching processes.

[0073] The deposited film has applications including, but not limited to: computer chips, optical devices, magnetic information storage devices, coatings on support materials or substrates, micro - electromechanical systems (MEMS), nano - electromechanical systems, thin - film transistors (TFT), light - emitting diodes (LED), organic light - emitting diodes (OLED), IGZO, and liquid crystal displays (LCD).

[0074] Examples

[0075] Example 1: Preventing the growth of a silicon oxide film on a trench structure

[0076] Film deposition is carried out in a 300 mm plasma - enhanced atomic layer deposition (PEALD) apparatus using an FLR design. The reactor consists of an outer chamber and an inner chamber with dedicated pressure control. While all reactive chemicals flow into the inner reactor for deposition, an Ar flow goes to the outer chamber to maintain pressure. The method and its conditions are described in Table 2.

[0077] Table 2: Methods and conditions for preventing the growth of silicon oxide

[0078]

[0079]

[0080] Steps c to h of the above-described method can be repeated until the desired thickness is achieved.

[0081] Use Filmtek TM Measure the thickness and refractive index of the deposited film using a Filmtek 3000 reflectance and transmittance spectrometer, while examining the film quality using a scanning electron microscope (SEM) and a transmission electron microscope (TEM).

[0082] Use di-sec-butylaminosilane (DSBAS) as the deposition precursor, O 2 plasma as the oxygen source, and triethyl orthoacetate (TEOA) as the organic passivator to deposit a blank film of silicon oxide using the steps described in Table 2. The TEOA soak time varies between 0 seconds (no TEOA passivator) and 60 seconds. The susceptor temperature is set at 300 °C.

[0083] When no TEOA soak is used (0 seconds), the growth per cycle (GPC) is / cycle, while longer TEOA soak times prevent the growth of the silicon oxide film to / cycle.

[0084] Grow a silicon oxide film on a trench structure with an aspect ratio of 10:1 and an opening of 150 nm using a TEOA soak time of 0.5 seconds. The TEOA exposure time is selected in the sub-saturation mode, and thus the passivator exposure on top of the trench is higher than that at the bottom of the trench. The sub-saturation mode can vary depending on the type of ALD reactor and should be obtained via experiments similar to those in this example for a given ALD reactor.

[0085] TEM measurements of the silicon oxide film thickness deposited at different positions in the trench are shown in Table 3.

[0086] Table 3: SiO deposited on a trench structure with an aspect ratio of 10:1 2 Film thickness

[0087]

[0088] The film thickness at the top is thinner than that at the bottom, indicating that TEOA inhibits film deposition at the top part of the trench structure, thus allowing bottom-up gap filling when using shorter TEOA exposure.

[0089] Example 2: Preventing N from being used on the trench structure 2 Plasma-deposited SiN x Growth

[0090] Perform film deposition in a 300 mm PEALD apparatus using an FLR design. The reactor consists of an outer chamber and an inner chamber with dedicated pressure control. While all reactive chemicals flow into the inner reactor for deposition, an Ar flow to the outer chamber maintains the pressure. The method and its conditions are described in Table 4 below.

[0091] Table 4: Blocking SiN x Growth methods and conditions

[0092]

[0093]

[0094] In this method, steps 3 to 9 can be repeated to obtain the desired thickness.

[0095] In this embodiment, di-sec-butylaminosilane (DSBAS) is used as the silicon precursor. Triethyl orthoacetate (TEOA) is used as the organic blocker, with a 0 - 10 second flow. Filmtek TM 3000 Reflectance and Transmittance Meter is used to measure the thickness and refractive index of the deposited film.

[0096] Table 5 below shows the role of TEOA in reducing the SiN x film GPC. It shows that after each 10 - second TEOA exposure cycle, the film growth is reduced to / cycle. This is approximately 45% lower in GPC than the film growth without TEOA passivation, and demonstrates the dose sensitivity of the passivation method.

[0097] Table 5: GPC of SiN film growth after TEOA exposure x GPC of film growth

[0098]

[0099] The growth of silicon nitride (SiN x ) film is explored on a trench structure with an aspect ratio of 10:1 and an opening of 150 nm using a 0.5 - second TEOA soak time. The TEOA exposure time is selected in the sub - saturation mode. Thus, the exposure of the passivant on the top of the trench is higher than that at the bottom of the trench.

[0100] TEM measurements of the thickness of the silicon nitride film deposited at different positions in the trench are shown in Table 6.

[0101] Table 6: SiN deposited on trench structures with an aspect ratio of 10:1 x Film thickness

[0102]

[0103] The film thickness at the top is thinner than that at the bottom, indicating that TEOA inhibits the film deposition at the top part of the trench structure, thus allowing bottom - to - top filling film deposition when using a shorter TEOA exposure.

[0104] Example 3. Growth of a silicon oxide film on a trench structure without a passivator

[0105] Film deposition is carried out in a 300 mm plasma enhanced atomic layer deposition (PEALD) apparatus using an FLR design. The reactor consists of an outer chamber and an inner chamber with dedicated pressure control. While all reactive chemicals flow into the inner reactor for deposition, an Ar flow goes to the outer chamber to maintain the pressure. The method and its conditions are described in Table 7.

[0106] Table 7: Methods and conditions for the growth of a silicon oxide film without a passivator

[0107]

[0108]

[0109] Steps c to f can be repeated multiple times to fill the gap.

[0110] In this example, di-sec-butylaminosilane (DSBAS) is used as the deposition precursor, and O 2 plasma is used as the oxygen source, and silicon oxide is deposited using the method and conditions listed in Table 7 above.

[0111] The TEM measurement results of the silicon oxide films deposited at different positions are shown in Table 8 below.

[0112] Table 8: SiO deposited on a trench structure with a 10:1 aspect ratio 2 Film thickness

[0113]

[0114] As shown in Table 8 above, the film deposited without a passivating agent has conformal film deposition.

[0115] Example 4: Growth of a film using a long passivator exposed within a trench structure

[0116] Except for the organic passivating agent soaking time, the method and conditions in this example are the same as those outlined in Table 2 above. Di-sec-butylaminosilane (DSBAS) is used as the deposition precursor, O 2 plasma is used as the oxygen source, and triethyl orthoacetate (TEOA) is used as the organic passivating agent to deposit a blank film of silicon oxide. The TEOA soaking time is selected to be 5 seconds.

[0117] The TEM measurement of the deposited film thickness at different positions in the trench is shown in Table 9.

[0118] Table 9: Thickness of the silicon oxide film deposited on a 10:1 trench structure.

[0119]

[0120] The film thickness at the top is similar to that at the bottom, indicating conformal deposition. This indicates that a longer passivating agent exposure time may not be suitable for bottom-up filling as it reacts uniformly with the surfaces (top and bottom) in the trench.

[0121] The foregoing description is merely representative, and thus embodiments described herein may be modified without departing from the scope of the present disclosure. Accordingly, such modifications fall within the scope of the present disclosure and are intended to fall within the scope of the appended claims.

Claims

1. An atomic layer deposition method for depositing a film into surface features of a substrate, the method comprising: a) placing the substrate having surface features with exposed hydroxyl groups into a reactor; b) heating the reactor to one or more temperatures from ambient temperature to 700 °C and optionally maintaining the reactor at a pressure of 100 Torr or less; c) introducing at least one organic passivating agent into the reactor to react with a portion of the exposed hydroxyl groups of the surface features; d) purging unreacted organic passivating agent from the reactor using an inert gas; e) introducing a precursor gas having at least one organic amino group to react with any unreacted hydroxyl groups of the surface features; f) purging unreacted precursor from the reactor using an inert gas; g) introducing an oxygen source or a nitrogen source into the reactor; and h) purging unreacted oxygen source or nitrogen source and any by-products using an inert gas, wherein steps c to h are repeated until the surface features are filled from bottom to top; and wherein the organic passivating agent comprises at least one compound selected from tetramethyl orthocarbonate, tetraethyl orthocarbonate, tetra-n-propyl orthocarbonate, trimethyl orthoacetate, triethyl orthoacetate, 1,1,1-triethoxypentane, 1,1,1-triethoxyheptane, triethyl orthobenzoate, 2,2-diethoxypropane, 1,1-diethoxy-1-phenylethane, 4,4-diethoxyheptane, 4,4-diethoxynonane, trimethyl orthoformate, and tri-n-propyl orthoformate; and wherein in step c, the at least one organic passivating agent is introduced by controlling the chamber pressure or the pulse time or the vapor flux of the organic passivating agent to react with those hydroxyl groups on the top surface region of the surface features, thereby allowing the precursor gas having at least one organic amino group to react with those unreacted hydroxyl groups on the bottom of the surface features in step e to anchor silicon- or metal-containing segments.

2. The method according to claim 1, wherein the organic passivating agent comprises at least one compound selected from trimethyl orthoacetate and triethyl orthoacetate.

3. The method according to claim 2, wherein the organic passivating agent comprises triethyl orthoacetate.

4. The method according to claim 1, wherein the precursor is selected from organoaminosilanes, organodiaminosilanes, organotrimethylsilylamines, organoaminosiloxanes, organocyclosiloxanes, and organoaminotitanium, organoaminohafnium, organoaminozirconium, organoaminotantalum, organoaminotungsten, organoaminomolybdenum, organoaminoaluminum, alkylaluminums, and metal alkoxides.

5. The method according to claim 1, wherein the oxygen source is selected from oxygen, oxygen plasma, water vapor plasma, a mixture of water and organic amine, hydrogen peroxide, nitrous oxide, ozone, carbon dioxide plasma, carbon monoxide plasma, and combinations thereof.

6. The method according to claim 1, wherein the nitrogen source is selected from ammonia, hydrazine, methyl hydrazine, 1,1-dimethyl hydrazine, N 2 plasma, ammonia plasma, hydrogen / nitrogen plasma, and combinations thereof.

7. The method according to claim 1, wherein the surface features have a depth-to-width aspect ratio of at least 2:

1.

8. The method according to claim 7, wherein the aspect ratio is at least 4:

1.

9. The method according to claim 7, wherein the surface feature has a width of 100 nm or less.

10. The method according to claim 1, wherein the surface feature is a via hole.

11. The method according to claim 1, wherein the surface feature is a groove.

12. The method according to claim 1, wherein the surface feature is a via hole and a groove.

13. The method according to claim 1, wherein the film produced each time after performing steps c) to h) is thicker towards the bottom of the surface feature than towards the top of the surface feature.

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