Metal oxide diffusion barriers
Various embodiments herein relate to methods, apparatus, and systems for forming an interconnect structure, or a portion thereof, on a substrate. In one example, the method includes receiving the substrate in a processing chamber, the substrate having dielectric material exposed within recessed features formed therein; exposing the substrate to plasma to thereby modify a top surface of the dielectric material; forming a metal oxide barrier layer on the modified top surface of the dielectric material, wherein the metal oxide barrier layer is formed through atomic layer deposition and/or chemical vapor deposition. In certain implementations, one or more additional step may be taken to improve processing results, for example to promote nucleation and/or adhesion of relevant layers.
1 . A method of forming an interconnect structure, or a portion thereof, on a substrate, the method comprising:
(a) receiving the substrate in a processing chamber, wherein the substrate comprises a dielectric material with recessed features formed in the dielectric material, wherein the interconnect structure is to be formed in the recessed features, and wherein the dielectric material is exposed within the recessed features;
(b) exposing the substrate to a plasma to thereby modify a top surface of the dielectric material;
(c) after (b), forming a metal oxide barrier layer on the modified top surface of the dielectric material, wherein the metal oxide barrier layer is formed, at least in part, through atomic layer deposition (ALD) and/or chemical vapor deposition (CVD); and
(d) after (c), exposing the substrate to a reducing gas or a reducing plasma generated from the reducing gas, thereby reducing a top surface of the metal oxide barrier layer and forming an in-situ metal liner on the metal oxide barrier layer.
2 . The method of claim 1 , wherein exposing the substrate to the plasma in (b) roughens the top surface of the dielectric material.
3 . The method of claim 1 , wherein exposing the substrate to the plasma in (b) promotes nucleation of the metal oxide barrier layer in (c) and improves adhesion between the dielectric material and the metal oxide barrier layer.
4 . The method of claim 1 , wherein exposing the substrate to the plasma in (b) comprises exposing the substrate to the plasma generated from a process gas selected from the group consisting of: H 2 , O 2 , NH 3 , CO 2 , N 2 O, N 2 , and combinations thereof.
5 . The method of claim 1 , wherein forming the metal oxide barrier layer comprises (i) forming a first portion of the metal oxide barrier layer through thermal ALD or thermal CVD, and (ii) forming a second portion of the metal oxide barrier layer through plasma enhanced ALD (PEALD) or plasma enhanced CVD (PECVD), wherein the first portion of the metal oxide barrier layer is formed before the second portion of the metal oxide barrier layer.
6 . The method of claim 1 , wherein the metal oxide barrier layer is formed using a metal-containing reactant selected from the group consisting of: a magnesium-containing reactant, a titanium-containing reactant, a molybdenum-containing reactant, a tungsten-containing reactant, a ruthenium-containing reactant, a cobalt-containing reactant, a copper-containing reactant, a zinc-containing reactant, an aluminum-containing reactant, an indium-containing reactant, a tin-containing reactant, a manganese-containing reactant, and combinations thereof.
7 . The method of claim 6 , wherein the metal-containing reactant is selected from the group consisting of: bis(1,4-di-tert-butyl-diazadiene)magnesium, bis(ethylcyclopentadienyl)magnesium, tetrakis(dimethylamido)titanium, hexafluoromolybdenum, pentachloromolybdenum, molybdenum dichloride dioxide, molybdenum tetrachloride oxide, molybdenum hexacarbonyl, hexachlorotungsten, dodecacarbonyltriruthenium, octacarbonyldicobalt, bis(dimethylamino-2-propoxy)copper, bis(dimethylaminoethoxy)copper, bis(diethylamino-2-propoxy)copper, bis(ethylmethylamino-2-propoxy)copper, bis(dimethylamino-2-methyl-2-butoxy)copper, bis(N,N′-di-sec-butylacetamidinate)dicopper, dimethylzinc, diethylzinc, diallylzinc, bis(2-methylallyl)zinc, trimethylaluminum, trimethylindium, tetrakis(dimethylamido)tin, tin(IV) chloride, tin(IV) chloride, tin(IV) bromide, stannane, trimethyltin chloride, dimethyltin dichloride, methyltin trichloride, tetraethyltin, tetramethyltin, dibutyltin diacetate, (dimethylamino)trimethyltin(IV), bis[bis(trimethylsilyl)amino]tin(II), dibutyldiphenyltin, hexaphenylditin(IV), tetraallyltin, tetrakis(diethylamino)tin(IV), tetravineyltin, tin(II)acetylacetonate, tricyclohexyltin hydride, trimethyl(phenylethynyl)tin, trimethyl(phenyl)tin, tetrakis(ethylmethylamino)tin, tin(II)(1,3-bis(1,1-dimethylethyl)-4,5-dimethyl-(4R,5R)-1,3,2-diazastannolidin-2-ylidene, N 2 ,N 3 -di-tert-butyl-butane-2,4-diamino-tin(II), bis(cyclopentadienyl)manganese, bis(ethylcyclopentadienyl)manganese, bis(tetramethylcyclopentadienyl)manganese, bis(pentamethylcyclopentadienylmanganese, bis(1,4-di-tert-butyl-diazadiene)manganese, bis(bis(trimethylsilylamido))manganese, bis(bis(ethyldimethylsilylamido))manganese, bis(N,N′-diisopropylpentylamidinato)manganese, and combinations thereof.
8 . The method of claim 1 , wherein (d) comprises exposing the substrate to the reducing gas, and wherein exposing the substrate to the reducing gas improves an adhesion of a subsequently deposited layer.
9 . The method of claim 8 , wherein the subsequently deposited layer is a metal seed layer or a metal nitride seed layer precursor.
10 . The method of claim 1 , wherein (d) comprises exposing the substrate to the reducing gas, and wherein the reducing gas comprises H 2 and/or a molecule that includes both nitrogen and hydrogen.
11 . The method of claim 1 , further comprising:
after (c), forming a metal seed layer or a metal nitride seed layer precursor on the substrate through the ALD or the CVD.
12 . The method of claim 11 , wherein the metal seed layer or metal nitride seed layer precursor comprise a metal selected from the group consisting of: copper, cobalt, iridium, molybdenum, palladium, ruthenium, tungsten, and combinations thereof.
13 . The method of claim 11 , wherein the metal seed layer or metal nitride seed layer precursor are deposited using a metal-containing reactant selected from the group consisting of: a molybdenum-containing reactant, a tungsten-containing reactant, a ruthenium-containing reactant, a cobalt-containing reactant, an iridium-containing reactant, a copper-containing reactant, a palladium-containing reactant, and combinations thereof.
14 . The method of claim 13 , wherein the metal-containing reactant is selected from the group consisting of: hexafluoromolybdenum, pentachloromolybdenum, molybdenum dichloride dioxide, molybdenum tetrachloride oxide, molybdenum hexacarbonyl, hexafluorotungsten, hexachlorotungsten, pentachlorotungsten, bis(tert-butylimido)bis(dimethylamido)tungsten, dodecacarbonyltriruthenium, (2,4-dimethylpentadienyl)ethylcyclopentadienylruthenium, (1-ethyl-1,4-cyclohexadienyl)ethylbenzeneruthenium, bis(ethylcyclopentadienyl)ruthenium, tetraoxoruthenium, octacarbonyldicobalt, (2-tert-butylallyl)tricabonylcobalt, (3,3-dimethyl-1-butyne)hexacarbonyldicobalt, cyclopentadienyldicarbonylcobalt, bis(1,4-diisopropyl-diazadiene)cobalt, bis(1,4-di-tert-butyl-diazadiene)cobalt, bis(N,N′-diisopropylacetamidinato)cobalt, bis(N-tert-butyl-N′-ethylpropanimidamidinato)cobalt, tris(acetylacetonate)iridium, bis(dimethylamino-2-propoxy)copper, bis(dimethylaminoethoxy)copper, bis(diethylamino-2-propoxy)copper, bis(ethylmethylamino-2-propoxy)copper, bis(dimethylamino-2-methyl-2-butoxy)copper bis(N,N′-di-sec-butylacetamidinate)dicopper, 1-methylallyl(hexafluoroacetylacetonato)-palladium(II), bis(hexafluoroacetylacetonato)palladium, and combinations thereof.
15 . The method of claim 11 , further comprising forming a liner on the metal oxide barrier layer through the ALD and/or the CVD, wherein the liner is formed prior to formation of the metal seed layer or the metal nitride seed layer precursor.
16 . The method of claim 11 , further comprising exposing the substrate to an anneal process or a plasma treatment process to thereby convert the metal nitride seed layer precursor to the metal seed layer.
17 . The method of claim 16 , wherein the anneal process or the plasma treatment process converts a copper nitride seed layer precursor to a copper seed layer.
18 . The method of claim 1 , wherein forming the metal oxide barrier layer in (c) comprises (i) forming a barrier layer precursor comprising at least one material selected from the group consisting of an elemental metal, a metal carbide, and a metal nitride, wherein the barrier layer precursor is formed through the ALD and/or the CVD, and (ii) exposing the barrier layer precursor to an oxygen-containing atmosphere to thereby convert the barrier layer precursor to the metal oxide barrier layer.
19 . A system for forming an interconnect structure, or a portion thereof, on a substrate, the system comprising:
a. a first processing chamber; and
b. a controller having at least one processor and a memory, wherein the at least one processor and the memory are communicatively connected with one another, and the memory stores computer-executable instructions for controlling the at least one processor to cause:
(i) receiving the substrate in the first processing chamber, wherein the substrate comprises a dielectric material with recessed features formed in the dielectric material, wherein the interconnect structure is to be formed in the recessed features, and wherein the dielectric material is exposed within the recessed features;
(ii) exposing the substrate to a plasma in the first processing chamber to thereby modify a top surface of the dielectric material;
(iii) after (ii), forming a metal oxide barrier layer on the modified top surface of the dielectric material, wherein the metal oxide barrier layer is formed, at least in part, through atomic layer deposition (ALD) and/or chemical vapor deposition (CVD); and
(iv) after (iii), exposing the substrate to a reducing gas or a reducing plasma generated from the reducing gas, thereby reducing a top surface of the metal oxide barrier layer and forming an in-situ metal liner on the metal oxide barrier layer.
20 . The system of claim 19 , further comprising a second processing chamber, wherein the memory stores computer-executable instructions for controlling the at least one processor to cause:
transferring the substrate from the first processing chamber to the second processing chamber, and
forming a metal seed layer or a metal nitride seed layer precursor on the metal oxide barrier layer through the ALD and/or the CVD while the substrate is positioned in the second processing chamber.
21 . The system of claim 20 , wherein the memory stores computer-executable instructions for controlling the at least one processor to cause:
prior to forming the metal seed layer or the metal nitride seed layer precursor, exposing the substrate to a reducing gas or a reducing plasma in the second processing chamber, thereby reducing an upper surface of the metal oxide barrier layer and forming an in-situ metal liner, wherein the metal seed layer or metal nitride seed layer precursor forms on the in-situ metal liner.
22 . The system of claim 21 , wherein the substrate is not exposed to atmosphere between exposing the substrate to the reducing gas or the reducing plasma and forming the metal seed layer or the metal nitride seed layer precursor.
23 . The system of claim 20 , wherein the memory stores computer-executable instructions for controlling the at least one processor to cause:
exposing the substrate to an anneal process or a plasma treatment process to thereby convert the metal nitride seed layer precursor to the metal seed layer.
24 . The system of claim 20 , wherein at least one of the first and second processing chambers is configured to deposit a liner on the metal oxide barrier layer, and wherein the liner is deposited through the ALD and/or the CVD.
25 . The system of claim 20 , wherein the first processing chamber is positioned on a first apparatus and the second processing chamber is positioned on a second apparatus.
26 . The system of claim 25 , further comprising a third processing chamber, wherein the memory stores computer-executable instructions for controlling the at least one processor to cause:
transferring the substrate from the second processing chamber to the third processing chamber and electroplating metal onto the metal seed layer while the substrate is in the third processing chamber.
27 . The system of claim 26 , wherein the second processing chamber and the third processing chamber are each part of the second apparatus.
28 . The system of claim 26 , wherein the memory stores computer-executable instructions for controlling the at least one processor to cause:
transferring the substrate from the second processing chamber to the third processing chamber without exposing the substrate to atmosphere.
29 . The system of claim 24 , wherein the memory stores computer-executable instructions for controlling the at least one processor to cause:
exposing the substrate to atmosphere while transferring the substrate from the first processing chamber to the second processing chamber.
30 . The system of claim 19 , wherein the memory stores computer-executable instructions for controlling the at least one processor to cause:
forming the metal oxide barrier layer by (i) forming a barrier layer precursor comprising at least one material selected from the group consisting of an elemental metal, a metal carbide, and a metal nitride, wherein the barrier layer precursor is formed through the ALD and/or the CVD, and (ii) exposing the barrier layer precursor to an oxygen-containing atmosphere to thereby convert the barrier layer precursor to the metal oxide barrier layer.