WO2019007871A1 - Process for the etching metal- or semimetal-containing materials - Google Patents

Process for the etching metal- or semimetal-containing materials Download PDF

Info

Publication number
WO2019007871A1
WO2019007871A1 PCT/EP2018/067745 EP2018067745W WO2019007871A1 WO 2019007871 A1 WO2019007871 A1 WO 2019007871A1 EP 2018067745 W EP2018067745 W EP 2018067745W WO 2019007871 A1 WO2019007871 A1 WO 2019007871A1
Authority
WO
WIPO (PCT)
Prior art keywords
semimetal
metal
compound
general formula
containing material
Prior art date
Application number
PCT/EP2018/067745
Other languages
French (fr)
Inventor
Torben ADERMANN
Stephan ZUEND
Hagen Wilmer
Falko ABELS
Original Assignee
Basf Se
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Basf Se filed Critical Basf Se
Publication of WO2019007871A1 publication Critical patent/WO2019007871A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F1/00—Etching metallic material by chemical means
    • C23F1/10—Etching compositions
    • C23F1/12—Gaseous compositions
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
    • H01L21/30604—Chemical etching
    • H01L21/30612—Etching of AIIIBV compounds
    • H01L21/30621—Vapour phase etching
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3105—After-treatment
    • H01L21/311—Etching the insulating layers by chemical or physical means
    • H01L21/31105—Etching inorganic layers
    • H01L21/31111—Etching inorganic layers by chemical means
    • H01L21/31116—Etching inorganic layers by chemical means by dry-etching
    • H01L21/31122—Etching inorganic layers by chemical means by dry-etching of layers not containing Si, e.g. PZT, Al2O3
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
    • H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
    • H01L21/321—After treatment
    • H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
    • H01L21/32133—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only
    • H01L21/32135—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only by vapour etching only

Definitions

  • the present invention is in the field of etching metal- or semimetal-containing materials by atomic layer etching.
  • metal- or semimetal-containing materials with fine structures serve different purposes such as dielectrics, conducting features, capping, or separation of fine structures.
  • Classical etching processes are wet chemical processes. These processes have the drawback that very fine structures can often not be reached. Also, process control, e.g. with regard to the thickness of material which is removed, is limited. Vapor-based technologies, in particular atomic layer etching, overcome these limitations.
  • US 2015 / 0 270 140 A1 discloses a process for etching a metal- or semimetal-containing material including halogenation of the surface by a plasma including a halide-containing compound
  • US 8 608 973 discloses a process for etching a metal- or semimetal-containing material including halogenation of the surface by a plasma including PF3 or COF2.
  • the known methods are not sufficiently reliable to only halogenate the topmost atomic layer only which is the key to high control over the etch process.
  • plasmas tend to halogenate the more exposed surfaces stronger than the less exposed surfaces.
  • the process was aimed to be fast, easy to handle and applicable to a broad variety of different metals.
  • X is CI or Br.
  • the present invention further relates to the use of an organic compound of general formula (I), (II) or (III) for an etching process.
  • the metal- or semimetal-containing material can contain any metal or semimetal including Mg, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os Ir, Pt, Au. Transition metals or silicon are preferred, in particular Ti, Fe, Co, Ni, Ru, Pd, Ta, W, Pt.
  • the metal- or semimetal-containing material contains at least 50 at-% metal and/or semimetal, more preferably at least 70 at-%, even more preferably at least 90 at-%, in particular at least 99 at-%.
  • At-% means as typical in the field that all metals and/or semimetal atoms contained in the material together represent the given percentage of total atoms in the material.
  • the metal- or semimetal-containing material is brought in contact with an organic compound of general formula (I), (II) or (III) in the gaseous phase.
  • R is hydrogen, an alkyl, an alkenyl or an aryl group.
  • An alkyl group can be linear or branched.
  • Examples for a linear alkyl group are methyl, ethyl, n- propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl.
  • Examples for a branched alkyl group are iso-propyl, iso-butyl, sec-butyl, tert-butyl, 2-methyl-pentyl, 2-ethyl-hexyl, cyclo- propyl, cyclohexyl, indanyl, norbornyl.
  • the alkyl group is a Ci to Cs alkyl group, more preferably a Ci to C6 alkyl group, in particular a Ci to C 4 alkyl group, such as methyl, ethyl, iso- propyl or tert-butyl.
  • Alkyl groups can be substituted, for example by halogens such as F, CI, Br, I, in particular F; by hydroxyl groups; by ether groups; or by amines such as dialkylamines.
  • An alkenyl group contains at least one carbon-carbon double bond.
  • the double bond can include the carbon atom with which the alkenyl group is bound to the rest of the molecule, or it can be placed further away from the place where the alkenyl group is bound to the rest of the molecule, preferably it is placed further away from the place where the alkenyl group is bound to the rest of the molecule.
  • Alkenyl groups can be linear or branched.
  • linear alkenyl groups in which the double bond includes the carbon atom with which the alkenyl group is bound to the rest of the molecule include 1-ethenyl, 1 -propenyl, 1-n-butenyl, 1 -n-pentenyl, 1 -n- hexenyl, 1 -n-heptenyl, 1 -n-octenyl.
  • linear alkenyl groups in which the double bond is placed further away from the place where alkenyl group is bound to the rest of the molecule include 1-n-propen-3-yl, 2-buten-1-yl, 1-buten-3-yl, 1-buten-4-yl, 1 -hexen-6-yl.
  • Examples for branched alkenyl groups in which the double bond includes the carbon atom with which alkenyl group is bound to the rest of the molecule include 1 -propen-2-yl, 1-n-buten-2-yl, 2-buten-2-yl, cyclopenten-1-yl, cyclohexen-1-yl.
  • Examples for branched alkenyl groups in which the double bond is placed further away from the place where alkenyl group is bound to the rest of the molecule include 2-methyl-1 -buten-4-yl, cyclopenten-3-yl, cyclohexene-3-yl.
  • Examples for an alkenyl group with more than one double bonds include 1 ,3-butadien-1 -yl, 1 ,3-butadien-2-yl, cylopenta- dien-5-yl.
  • Aryl groups include aromatic hydrocarbons such as phenyl, naphthalyl, anthrancenyl, phenan- threnyl groups and heteroaromatic groups such as pyrryl, furanyl, thienyl, pyridinyl, quinoyl, benzofuryl, benzothiophenyl, thienothienyl.
  • aromatic hydrocarbons such as phenyl, naphthalyl, anthrancenyl, phenan- threnyl groups and heteroaromatic groups such as pyrryl, furanyl, thienyl, pyridinyl, quinoyl, benzofuryl, benzothiophenyl, thienothienyl.
  • Several of these groups or combinations of these groups are also possible like biphenyl, thienophenyl or furanylthienyl.
  • Aryl groups can be substituted for example by halogens like fluoride, chloride, bromide, iodide; by pseudohalogens like cyanide, cyanate, thiocyanate; by alcohols; alkyl chains or alkoxy chains.
  • Aromatic hydrocarbons are preferred, phenyl is more preferred.
  • E stands for C bearing two further organic groups includ- ing hydrogen or N bearing one further organic group including hydrogen.
  • An organic group is any group which contains carbon, hydrogen, oxygen, nitrogen, sulfur and/or phosphor.
  • an organic group is hydrogen, an alkyl group, an alkenyl group, an alkoxy group, an acyl group, an acyl oxy group, an ester group, an amide group, an amine group, an aryl group or an aryloxy group.
  • alkyl, alkenyl and aryl as described above apply also for E. If E is C bearing two further organic groups, these can be the same or different to each other, preferably one of these groups is hydrogen.
  • the compound of general formula (I) is a compound of general formula (la).
  • the two A can be the same or different to each other, preferably they are the same, in particular both A are C.
  • the two R can be the same or different to each other, preferably they are the same.
  • the compound of general formula (I) is a compound of general formula (lb) or (lc).
  • R (lb) (lc)
  • the four R can be the same or different to each other.
  • the same definitions for R as described above apply. Some preferred examples are shown below.
  • the compound of general formula (III) is a compound of general formula (Ilia), (lllb) or (lllc).
  • the two or three R can be the same or different to each other.
  • the same definitions for R as de scribed above apply. Some preferred examples are shown below.
  • the molecular weight of the organic compound of general formula (I), (II) or (III) is not more than 1000 g/mol, more preferred not more than 800 g/mol, in particular not more than 600 g/mol.
  • the compound of general formula (I), (II), or (III) is in the vapor phase when brought in contact with the surface of the metal- or semimetal-containing material. It can be used as pristine compound or mixed with an inert gas, for example He, Ne, or Ar.
  • a halogenation reaction occurs producing partially or fully halogenated metal and/or semimetal atoms. The reaction usually takes between 1 s and 1 min, for example 5 to 20 s.
  • the pressure of the vapor phase during the halogenation reaction is typically 1 to 100 mbar, preferably 2 to 50 mbar, such as 5 to 20 mbar.
  • the halogenation reaction rate on the surface can be increased by increasing of the temperature, such as to 50 °C or to 300 °C, preferably 100 °C to 200 °C.
  • any residual vapor is removed by purging with an inert gas, for example nitrogen, helium, or argon.
  • the residual vapor can be removed by high vacuum, such as lowering the pressure to 0.1 to 10 -6 mbar.
  • the compound of general formula (I), (II), or (III) is used in the process according to the present invention is preferably used at high purity to achieve the best results.
  • High purity means that the substance employed contains at least 90 wt.-% of the organic compound, preferably at least 95 wt.-%, more preferably at least 98 wt.-%, in particular at least 99 wt.-%.
  • the purity can be determined by elemental analysis according to DIN 51721 (Prufung fester Brennstoffe - Beêt des Gehaltes an Kohlenstoff und Wasserstoff -maschine nach Radmacher-Hoverath, August 2001 ).
  • the metal- or semimetal-containing material is brought in contact with a compound of general formula (I), (II), or (III), the metal- or semimetal-containing material is brought in contact with a coordinating compound, i.e. a compound which can form a coordinative bond with the metal or semimetal in the metal- or semimetal-containing material.
  • the coordinating compound is preferably able to convert the halogenated metal or semimetal atoms of the metal or semimetal in the metal- or semimetal-containing material into a volatile complex. In this way, the halogenated metal or semimetal compounds can be removed while the non-halogenated metal or semimetal atoms remain in the metal- or semimetal-containing material. In this case the complexation and removal reaction is self-limiting.
  • the metal- or semimetal-containing material is brought in contact with a coordinating compound in the gaseous state.
  • coordinating compounds can be employed including amines, phosphanes, hydrogen, NO, CO, and ethylene.
  • the coordinating compound contains at least one nitrogen, oxygen, or phosphor atom which can coordinate a metal or semimetal.
  • coordinating compounds containing a nitrogen atom which can coordinated a metal or semimetal include amines like trimethylamine, triphenylamine, dimethylamino-iso-pro- panol.
  • the coordinating compound contains two or more nitrogen atoms including ethylenediamine derivatives like ⁇ , ⁇ , ⁇ ', ⁇ '-tetramethylethylenediamine or N,N,N',N",N"-pen- tamethyldiethylenetriamine; imines like 2,4-pentandione-N-alkylimines, 2,4-pentandione-N-iso- propylimine, glyoxal-N,N'-bis-isopropyl-diimine, glyoxal-N,N'-bis-tert-butyl-diimine or 2,4-pen- tanedione-diimine; diketiminates such as N,N'-2,4-pentanediketiminate; iminopyrroles including pyrrol-2-carbald-alkylimines such as pyrrol-2-carbald-ethylimine, pyrrol-2-carbald-iso-propy- limine or
  • Examples for coordinating compounds containing an oxygen atom which can coordinated a metal or semimetal include alkanolates, tetrahydrofurane, acetylacetonate, or 1 ,1 ,1 , 5,5, 5-pen- tafluoroacetylacetone.
  • Other suitable examples for coordinating compounds contain both a nitrogen and an oxygen atom which both coordinate to M including dimethylamino-iso-propanol, formamide, acetamide, 2,4-pentandione-N-alkylimines such as 2,4-pentandione-N-iso-propy- limine.
  • Examples for coordinating compounds containing a phosphor atom which can coordinated a metal or semimetal include phosphane or trisubstituted phosphanes including trihalogenphos- phanes, trialkylphosphanes, dialkylarylphosphanes, alkyl-diarylphosphanes or tri- arylphosphanes, wherein the alkyl or the aryl groups can be the same or different to each other if more than one alkyl or aryl group is present.
  • the coordinating compound contains two or more phosphor atoms.
  • Such compounds include diphosphinoethanes such as 1 ,2-bis(dieth- ylphosphino)ethane.
  • the coordinating compound contains a group which is capable of forming a volatile compound with a halogen atom, for example groups containing Si, B, Sn or Ge.
  • a volatile compound for example groups containing Si, B, Sn or Ge.
  • the removal of such a volatile compound is another driving force to form a coordinative bond to the metal or semimetal in the metal- or semimetal-containing material.
  • Preferred examples include silylated amines such as N,N-dimethyl-N-trimethylsilylamine; silylated alcohols such as meth- oxy-trimethylsilane; silylated carboxylates such as trimethylsilyl acetate; silylated diamines such as N,N'-bis(trimethylsilyl)-N,N'-di-tertbutyl-ethen-1 ,2-diamine; diketiminates of Sn or Ge; amidinates of Sn or Ge; or borylated cyclopentadiene such as cyclopentadiene-boron-dichloride.
  • silylated amines such as N,N-dimethyl-N-trimethylsilylamine
  • silylated alcohols such as meth- oxy-trimethylsilane
  • silylated carboxylates such as trimethylsilyl acetate
  • silylated diamines such as N,N'-bis(tri
  • any residual excess coordinating compound is removed by purging with an inert gas, for example nitrogen, helium, or argon.
  • an inert gas for example nitrogen, helium, or argon.
  • the excess coordinating compound can be removed by high vacuum, such as lowering the pressure to 0.1 to 10 -6 mbar.
  • the halogenated metal- or semimetal-containing material in contact with an organic solvent prior to bringing it in contact with a coordinating compound.
  • the solvent is in the vapor phase when being brought in contact with the metal- or semimetal-containing material.
  • the pressure of the solvent vapor is 1 to 100 mbar, more preferably 2 to 50 mbar, in particular 5 to 20 mbar.
  • Organic solvents include alcohols like methanol, ethanol or isopropanol; ethers like dimethylether, diethylether or tetrahydrofurane; es- ters like methyl formiate, ethyl formiate, methyl acetate, ethyl actetate; aldehydes like formaldehyde or acetaldehyde; ketones like acetone or methyl ethyl ketone; acids like formic acid or acetic acid; amines like trimethyl amine, triethylamine, dimethyl-isopropylamine; amides like N,N- dimethylformamide or N,N-dimethylacetamide.
  • any residual solvent vapor is removed by purging with an inert gas, for example nitrogen, helium, or argon.
  • the residual vapor can be removed by high vacuum, such as lowering the pressure to 0.1 to 10 "6 mbar.
  • the sequence including bringing the metal- or semimetal-containing material in contact with a compound of general formula (I), (II), or (III) and then bringing it in contact with a coordinating compound is performed at least twice, more preferably at least five times, in particular at least 10 times.
  • ALE atomic layer etching
  • passivating layers such as photocured resins which are irradiated through shadow masks, in order to selectively etch metals or semimetals only in particular areas for building up complex structures.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Computer Hardware Design (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Drying Of Semiconductors (AREA)

Abstract

The present invention is in the field of etching metal- or semimetal-containing materials by atomic layer etching. In particular the present invention relates to a process for etching a metal- or semimetal-containing material comprising bringing a metal- or semimetal-containing material in contact with an organic compound of general formula (I), (II) or (III) in the gaseous phase formula (I) (II) (III) wherein R is hydrogen, an alkyl, an alkenyl or an aryl group, A is C, S, S=O, P-X or P-R, E is C bearing two further organic groups including hydrogen or N bearing one further organic group including hydrogen, X is Cl or Br.

Description

Process for the Etching Metal- or Semimetal-Containing Materials Description The present invention is in the field of etching metal- or semimetal-containing materials by atomic layer etching.
With the ongoing miniaturization, e.g. in the semiconductor industry, the need for metal- or semimetal-containing materials with fine structures increases while the requirements of the quality of such materials become stricter. Thin metal- or semimetal-containing materials serve different purposes such as dielectrics, conducting features, capping, or separation of fine structures. Classical etching processes are wet chemical processes. These processes have the drawback that very fine structures can often not be reached. Also, process control, e.g. with regard to the thickness of material which is removed, is limited. Vapor-based technologies, in particular atomic layer etching, overcome these limitations.
US 2015 / 0 270 140 A1 discloses a process for etching a metal- or semimetal-containing material including halogenation of the surface by a plasma including a halide-containing compound
Figure imgf000002_0001
US 8 608 973 discloses a process for etching a metal- or semimetal-containing material including halogenation of the surface by a plasma including PF3 or COF2.
However, the known methods are not sufficiently reliable to only halogenate the topmost atomic layer only which is the key to high control over the etch process. In particular when halogenating uneven surfaces, plasmas tend to halogenate the more exposed surfaces stronger than the less exposed surfaces.
It was an object of the present invention to provide a process for etching metal- or semimetal- containing materials with increased control of the amount of removed material independent of the surface topology. The process was aimed to be fast, easy to handle and applicable to a broad variety of different metals.
These objects were achieved by a process for etching a metal- or semimetal-containing material comprising bringing a metal- or semimetal-containing material in contact with an organic compound of general formula (I), (II) or (III) in the gaseous phase
Figure imgf000002_0002
(I) (III) wherein R is hydrogen, an alkyl, an alkenyl or an aryl group,
A is C, S, S=0, P-X or P-R, E is C bearing two further organic groups including hydrogen or N bearing one further organic group including hydrogen,
X is CI or Br. The present invention further relates to the use of an organic compound of general formula (I), (II) or (III) for an etching process.
Preferred embodiments of the present invention can be found in the description and the claims. Combinations of different embodiments fall within the scope of the present invention.
The metal- or semimetal-containing material can contain any metal or semimetal including Mg, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os Ir, Pt, Au. Transition metals or silicon are preferred, in particular Ti, Fe, Co, Ni, Ru, Pd, Ta, W, Pt. Preferably, the metal- or semimetal-containing material contains at least 50 at-% metal and/or semimetal, more preferably at least 70 at-%, even more preferably at least 90 at-%, in particular at least 99 at-%. "At-%" means as typical in the field that all metals and/or semimetal atoms contained in the material together represent the given percentage of total atoms in the material. According to the present invention the metal- or semimetal-containing material is brought in contact with an organic compound of general formula (I), (II) or (III) in the gaseous phase. R is hydrogen, an alkyl, an alkenyl or an aryl group.
An alkyl group can be linear or branched. Examples for a linear alkyl group are methyl, ethyl, n- propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl. Examples for a branched alkyl group are iso-propyl, iso-butyl, sec-butyl, tert-butyl, 2-methyl-pentyl, 2-ethyl-hexyl, cyclo- propyl, cyclohexyl, indanyl, norbornyl. Preferably, the alkyl group is a Ci to Cs alkyl group, more preferably a Ci to C6 alkyl group, in particular a Ci to C4 alkyl group, such as methyl, ethyl, iso- propyl or tert-butyl. Alkyl groups can be substituted, for example by halogens such as F, CI, Br, I, in particular F; by hydroxyl groups; by ether groups; or by amines such as dialkylamines.
An alkenyl group contains at least one carbon-carbon double bond. The double bond can include the carbon atom with which the alkenyl group is bound to the rest of the molecule, or it can be placed further away from the place where the alkenyl group is bound to the rest of the molecule, preferably it is placed further away from the place where the alkenyl group is bound to the rest of the molecule. Alkenyl groups can be linear or branched. Examples for linear alkenyl groups in which the double bond includes the carbon atom with which the alkenyl group is bound to the rest of the molecule include 1-ethenyl, 1 -propenyl, 1-n-butenyl, 1 -n-pentenyl, 1 -n- hexenyl, 1 -n-heptenyl, 1 -n-octenyl. Examples for linear alkenyl groups in which the double bond is placed further away from the place where alkenyl group is bound to the rest of the molecule include 1-n-propen-3-yl, 2-buten-1-yl, 1-buten-3-yl, 1-buten-4-yl, 1 -hexen-6-yl. Examples for branched alkenyl groups in which the double bond includes the carbon atom with which alkenyl group is bound to the rest of the molecule include 1 -propen-2-yl, 1-n-buten-2-yl, 2-buten-2-yl, cyclopenten-1-yl, cyclohexen-1-yl. Examples for branched alkenyl groups in which the double bond is placed further away from the place where alkenyl group is bound to the rest of the molecule include 2-methyl-1 -buten-4-yl, cyclopenten-3-yl, cyclohexene-3-yl. Examples for an alkenyl group with more than one double bonds include 1 ,3-butadien-1 -yl, 1 ,3-butadien-2-yl, cylopenta- dien-5-yl.
Aryl groups include aromatic hydrocarbons such as phenyl, naphthalyl, anthrancenyl, phenan- threnyl groups and heteroaromatic groups such as pyrryl, furanyl, thienyl, pyridinyl, quinoyl, benzofuryl, benzothiophenyl, thienothienyl. Several of these groups or combinations of these groups are also possible like biphenyl, thienophenyl or furanylthienyl. Aryl groups can be substituted for example by halogens like fluoride, chloride, bromide, iodide; by pseudohalogens like cyanide, cyanate, thiocyanate; by alcohols; alkyl chains or alkoxy chains. Aromatic hydrocarbons are preferred, phenyl is more preferred.
In the compound of general formula (I) and (II) A stands for C, S, S=0, P-X or P-R, preferably C, S, or P-X, in particular C.
In the compound of general formula (I) E stands for C bearing two further organic groups includ- ing hydrogen or N bearing one further organic group including hydrogen. An organic group is any group which contains carbon, hydrogen, oxygen, nitrogen, sulfur and/or phosphor. Preferably, an organic group is hydrogen, an alkyl group, an alkenyl group, an alkoxy group, an acyl group, an acyl oxy group, an ester group, an amide group, an amine group, an aryl group or an aryloxy group. The definitions for alkyl, alkenyl and aryl as described above apply also for E. If E is C bearing two further organic groups, these can be the same or different to each other, preferably one of these groups is hydrogen.
Preferably, the compound of general formula (I) is a compound of general formula (la).
Figure imgf000004_0001
The two A can be the same or different to each other, preferably they are the same, in particular both A are C. The two R can be the same or different to each other, preferably they are the same. Some preferred examples of general formula (la) are given below.
Figure imgf000005_0001
Also preferably, the compound of general formula (I) is a compound of general formula (lb) or (lc).
Figure imgf000005_0002
(lb) (lc) The four R can be the same or different to each other. The same definitions for R as described above apply. Some preferred examples are shown below.
Figure imgf000005_0003
lb-1 lb-2 lc-1 lc-2 Some preferred examples of the compound of general formula (II) are shown below.
Figure imgf000005_0004
11-1
Figure imgf000005_0005
-10
Figure imgf000006_0001
Some preferred examples of the compound of general formula (III) are shown below.
Figure imgf000007_0001
Figure imgf000007_0002
111-7 111-8 111-9 111-10 111-11 111-12 Preferably, the compound of general formula (III) is a compound of general formula (Ilia), (lllb) or (lllc).
Figure imgf000007_0003
(Ilia) (lllb) (lllc)
The two or three R can be the same or different to each other. The same definitions for R as de scribed above apply. Some preferred examples are shown below.
Figure imgf000007_0004
Preferably the molecular weight of the organic compound of general formula (I), (II) or (III) is not more than 1000 g/mol, more preferred not more than 800 g/mol, in particular not more than 600 g/mol. The compound of general formula (I), (II), or (III) is in the vapor phase when brought in contact with the surface of the metal- or semimetal-containing material. It can be used as pristine compound or mixed with an inert gas, for example He, Ne, or Ar. Typically, a halogenation reaction occurs producing partially or fully halogenated metal and/or semimetal atoms. The reaction usually takes between 1 s and 1 min, for example 5 to 20 s. The pressure of the vapor phase during the halogenation reaction is typically 1 to 100 mbar, preferably 2 to 50 mbar, such as 5 to 20 mbar.
The halogenation reaction rate on the surface can be increased by increasing of the temperature, such as to 50 °C or to 300 °C, preferably 100 °C to 200 °C.
Preferably, after completion of the halogenation reaction, any residual vapor is removed by purging with an inert gas, for example nitrogen, helium, or argon. Alternatively, the residual vapor can be removed by high vacuum, such as lowering the pressure to 0.1 to 10-6 mbar. The compound of general formula (I), (II), or (III) is used in the process according to the present invention is preferably used at high purity to achieve the best results. High purity means that the substance employed contains at least 90 wt.-% of the organic compound, preferably at least 95 wt.-%, more preferably at least 98 wt.-%, in particular at least 99 wt.-%. The purity can be determined by elemental analysis according to DIN 51721 (Prufung fester Brennstoffe - Bestimmung des Gehaltes an Kohlenstoff und Wasserstoff - Verfahren nach Radmacher-Hoverath, August 2001 ).
Preferably, after the metal- or semimetal-containing material is brought in contact with a compound of general formula (I), (II), or (III), the metal- or semimetal-containing material is brought in contact with a coordinating compound, i.e. a compound which can form a coordinative bond with the metal or semimetal in the metal- or semimetal-containing material. The coordinating compound is preferably able to convert the halogenated metal or semimetal atoms of the metal or semimetal in the metal- or semimetal-containing material into a volatile complex. In this way, the halogenated metal or semimetal compounds can be removed while the non-halogenated metal or semimetal atoms remain in the metal- or semimetal-containing material. In this case the complexation and removal reaction is self-limiting. Preferably, the metal- or semimetal-containing material is brought in contact with a coordinating compound in the gaseous state.
Various coordinating compounds can be employed including amines, phosphanes, hydrogen, NO, CO, and ethylene. Preferably, the coordinating compound contains at least one nitrogen, oxygen, or phosphor atom which can coordinate a metal or semimetal. Examples for coordinating compounds containing a nitrogen atom which can coordinated a metal or semimetal include amines like trimethylamine, triphenylamine, dimethylamino-iso-pro- panol. Preferably, the coordinating compound contains two or more nitrogen atoms including ethylenediamine derivatives like Ν,Ν,Ν',Ν'-tetramethylethylenediamine or N,N,N',N",N"-pen- tamethyldiethylenetriamine; imines like 2,4-pentandione-N-alkylimines, 2,4-pentandione-N-iso- propylimine, glyoxal-N,N'-bis-isopropyl-diimine, glyoxal-N,N'-bis-tert-butyl-diimine or 2,4-pen- tanedione-diimine; diketiminates such as N,N'-2,4-pentanediketiminate; iminopyrroles including pyrrol-2-carbald-alkylimines such as pyrrol-2-carbald-ethylimine, pyrrol-2-carbald-iso-propy- limine or pyrrol-2-carbald-tert-butylimine as well as pyrrol-2,5-biscarbald-alkyldiimines such as pyrrol-2,5-biscarbald-tert-butyldiimine; amidinates such as acetamidine or N,N'-bis-iso-propyla- cetamidine; guanidinates such as guanidine; aminoimines such as 2-N-tert-butylamino-2- methylpropanal-N-tertbuylimine; amides such as formamide or acetamide.
Examples for coordinating compounds containing an oxygen atom which can coordinated a metal or semimetal include alkanolates, tetrahydrofurane, acetylacetonate, or 1 ,1 ,1 , 5,5, 5-pen- tafluoroacetylacetone. Other suitable examples for coordinating compounds contain both a nitrogen and an oxygen atom which both coordinate to M including dimethylamino-iso-propanol, formamide, acetamide, 2,4-pentandione-N-alkylimines such as 2,4-pentandione-N-iso-propy- limine.
Examples for coordinating compounds containing a phosphor atom which can coordinated a metal or semimetal include phosphane or trisubstituted phosphanes including trihalogenphos- phanes, trialkylphosphanes, dialkylarylphosphanes, alkyl-diarylphosphanes or tri- arylphosphanes, wherein the alkyl or the aryl groups can be the same or different to each other if more than one alkyl or aryl group is present. Examples include trifluoro phosphane, trimethyl phosphane, trimethoxyphosphane, methyl-dimethoxy phosphane, tri-tertbutyl phosphane, tricy- clohexyl phosphane, di-isopropyl-tert-butyl phosphane, dimethyl-tert-butyl phosphane, triphenyl phosphane, and tritolylphosphane. Preferably, the coordinating compound contains two or more phosphor atoms. Such compounds include diphosphinoethanes such as 1 ,2-bis(dieth- ylphosphino)ethane.
Preferably, the coordinating compound contains a group which is capable of forming a volatile compound with a halogen atom, for example groups containing Si, B, Sn or Ge. In this way, the removal of such a volatile compound is another driving force to form a coordinative bond to the metal or semimetal in the metal- or semimetal-containing material. Preferred examples include silylated amines such as N,N-dimethyl-N-trimethylsilylamine; silylated alcohols such as meth- oxy-trimethylsilane; silylated carboxylates such as trimethylsilyl acetate; silylated diamines such as N,N'-bis(trimethylsilyl)-N,N'-di-tertbutyl-ethen-1 ,2-diamine; diketiminates of Sn or Ge; amidinates of Sn or Ge; or borylated cyclopentadiene such as cyclopentadiene-boron-dichloride.
Preferably, after the metal- or semimetal-containing material is brought in contact with the coordinating compound, any residual excess coordinating compound is removed by purging with an inert gas, for example nitrogen, helium, or argon. Alternatively, the excess coordinating compound can be removed by high vacuum, such as lowering the pressure to 0.1 to 10-6 mbar.
In some cases it is preferable to bring the halogenated metal- or semimetal-containing material in contact with an organic solvent prior to bringing it in contact with a coordinating compound. Preferably, the solvent is in the vapor phase when being brought in contact with the metal- or semimetal-containing material. Preferably, the pressure of the solvent vapor is 1 to 100 mbar, more preferably 2 to 50 mbar, in particular 5 to 20 mbar. Organic solvents include alcohols like methanol, ethanol or isopropanol; ethers like dimethylether, diethylether or tetrahydrofurane; es- ters like methyl formiate, ethyl formiate, methyl acetate, ethyl actetate; aldehydes like formaldehyde or acetaldehyde; ketones like acetone or methyl ethyl ketone; acids like formic acid or acetic acid; amines like trimethyl amine, triethylamine, dimethyl-isopropylamine; amides like N,N- dimethylformamide or N,N-dimethylacetamide. Preferably, after bringing the metal- or semimetal-containing material in contact with an organic solvent, any residual solvent vapor is removed by purging with an inert gas, for example nitrogen, helium, or argon. Alternatively, the residual vapor can be removed by high vacuum, such as lowering the pressure to 0.1 to 10"6 mbar. Preferably, the sequence including bringing the metal- or semimetal-containing material in contact with a compound of general formula (I), (II), or (III) and then bringing it in contact with a coordinating compound is performed at least twice, more preferably at least five times, in particular at least 10 times.
A process containing multiple of said sequence is often referred to as atomic layer etching (ALE). ALE can be employed in the semiconductor manufacturing process, in particular when sub-10 nm technologies are involved. ALE is often combined with passivating layers, such as photocured resins which are irradiated through shadow masks, in order to selectively etch metals or semimetals only in particular areas for building up complex structures.

Claims

Claims
1. A process for etching a metal- or semimetal-containing material comprising bringing a metal- or semimetal-containing material in contact with an organic compound of general formula (I), (II) or (III) in the gaseous phase o R
I
X .A.
R- R' •x R X
(I) (N) (III) wherein R is hydrogen, an alkyl, an alkenyl or an aryl group,
A is C, S, S=0, P-X or P-R,
E is C bearing two further organic groups including hydrogen or N bearing one further organic group including hydrogen,
X is CI or Br. 2. The process according to claim 1 , wherein the compound of general formula (I), (II), or (III) is a compound of general formula (la).
Figure imgf000011_0001
3. The process according to claim 1 , wherein the compound of general formula (I), (II), or (III) is a compound of general formula (lb) or (Ic).
Figure imgf000011_0002
(lb) (Ic) 4. The process according to claim 1 , wherein the compound of general formula (I), (II), or (III) is a compound of general formula (Ilia), (1Mb), or (lllc).
Figure imgf000012_0001
(Ilia) (Mb) (Hie)
The process according to any of the claims 1 to 4, wherein the metal- or semimetal-containing material is brought in contact with a coordinating compound after the metal- or semimetal-containing material is brought in contact with a compound of general formula (I), (II), or
6. The process according to claim 5, wherein the sequence including bringing the metal- or semimetal-containing material in contact with a compound of general formula (I), (II), or (III) and bringing the metal- or semimetal-containing material in contact with a coordinating compound in performed at least five times.
7. The process according to any of the claims 1 to 6, wherein metal- or semimetal-containing material contains Ti, Fe, Co, Ni, Ru, Pd, Ta, W, or Pt.
8. The process according to any of the claims 1 to 7, wherein the metal- or semimetal-containing material is brought in contact with an organic compound of general formula (I), (II) or (III) at a temperature of 50 °C or to 300 °C. 9. The process according to any of the claims 1 to 8, wherein the coordinating compound contains at least one nitrogen, oxygen, or phosphor atom which can coordinate a metal or semimetal.
10. Use of an organic compound of general formula (I), (II) or (III) for an etching process.
PCT/EP2018/067745 2017-07-05 2018-07-02 Process for the etching metal- or semimetal-containing materials WO2019007871A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP17179835 2017-07-05
EP17179835.8 2017-07-05

Publications (1)

Publication Number Publication Date
WO2019007871A1 true WO2019007871A1 (en) 2019-01-10

Family

ID=59362919

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2018/067745 WO2019007871A1 (en) 2017-07-05 2018-07-02 Process for the etching metal- or semimetal-containing materials

Country Status (1)

Country Link
WO (1) WO2019007871A1 (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1215160A (en) * 1966-12-27 1970-12-09 Gen Electric Improvements in etching of gold
EP0701274A1 (en) * 1994-08-11 1996-03-13 Nippon Sanso Corporation Dry method for cleaning semiconductor substrate
WO2013170130A1 (en) * 2012-05-11 2013-11-14 Advanced Technology Materials, Inc. Formulations for wet etching nipt during silicide fabrication
US8608973B1 (en) 2012-06-01 2013-12-17 Lam Research Corporation Layer-layer etch of non volatile materials using plasma
US20150027014A1 (en) 2012-08-24 2015-01-29 Bluemedia, Inc. Systems and Methods for Bollard Cover Media Advertising
US20160293449A1 (en) * 2013-03-13 2016-10-06 Applied Materials, Inc. Methods Of Etching Films Comprising Transition Metals
WO2017099718A1 (en) * 2015-12-08 2017-06-15 Intel Corporation Atomic layer etching of transition metals by halogen surface oxidation

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1215160A (en) * 1966-12-27 1970-12-09 Gen Electric Improvements in etching of gold
EP0701274A1 (en) * 1994-08-11 1996-03-13 Nippon Sanso Corporation Dry method for cleaning semiconductor substrate
WO2013170130A1 (en) * 2012-05-11 2013-11-14 Advanced Technology Materials, Inc. Formulations for wet etching nipt during silicide fabrication
US8608973B1 (en) 2012-06-01 2013-12-17 Lam Research Corporation Layer-layer etch of non volatile materials using plasma
US20150027014A1 (en) 2012-08-24 2015-01-29 Bluemedia, Inc. Systems and Methods for Bollard Cover Media Advertising
US20160293449A1 (en) * 2013-03-13 2016-10-06 Applied Materials, Inc. Methods Of Etching Films Comprising Transition Metals
WO2017099718A1 (en) * 2015-12-08 2017-06-15 Intel Corporation Atomic layer etching of transition metals by halogen surface oxidation

Similar Documents

Publication Publication Date Title
EP3460827B1 (en) Compositions and methods using same for carbon doped silicon containing films
TW201040304A (en) Raw material for chemical vapor deposition, and process for forming silicon-containing thin film using same
EP1383939B1 (en) Use of perfluoroketones as vapor reactor cleaning, etching, and doping gases
KR102467887B1 (en) Reaction of Diazadiene Complex with Amines
JP6854294B2 (en) How to form a metal film
EP3348667A1 (en) Chemical vapor deposition feedstock comprising organic ruthenium compound and chemical vapor deposition method using said chemical vapor deposition feedstock
WO2019126655A1 (en) Methods for depositing blocking layers on conductive surfaces
KR20150084757A (en) Method for producing thin film containing molybdenum, thin film-forming starting material, and molybdenum imide compound
JP7425773B2 (en) Haloalkynyl dicobalt hexacarbonyl precursor for chemical vapor deposition of cobalt
JP2005068074A (en) Rare-earth metal complex, raw material for forming thin film, and method for producing thin film
WO2011006035A2 (en) Bis-ketoiminate copper precursors for deposition of copper-containing films
US10982336B2 (en) Method for etching a metal surface
KR20200063998A (en) Low halide lanthanum precursors for vapor deposition
US20140024814A1 (en) Precursor for formation of europium-containing thin film, and method for forming europium-containing thin film
JP6270183B2 (en) Organic / inorganic layered perovskite compound and method for producing organic / inorganic layered perovskite compound
CN115677747A (en) Preparation method of monoamino substituted silane
JP5480032B2 (en) Metal compounds, raw materials for forming thin films, and cyclopentadiene compounds
TWI784098B (en) Titanium-containing film forming compositions for vapor deposition of titanium-containing films
WO2019007871A1 (en) Process for the etching metal- or semimetal-containing materials
Chi et al. Fluorinated aminoalkoxide Cu II complexes: new CVD precursors for deposition of copper metal
JP5214191B2 (en) Thin film forming raw material and thin film manufacturing method
KR20160124025A (en) Group v-containing film forming compositions and vapor deposition of niobium-containing films
WO2018088078A1 (en) Compound, thin-film-forming raw material, thin-film-forming raw material for atomic-layer deposition method, and process for producing thin film
IL259109B2 (en) Process for the generation of metallic films
JP5583529B2 (en) Metal compounds and raw materials for thin film formation

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18735572

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18735572

Country of ref document: EP

Kind code of ref document: A1