CN1608143A - Photolytic conversion process to form patterned amorphous film - Google Patents

Abstract

The invention is directed to a photoresist-free method for depositing films composed of metals, (such as copper or silica), or their oxides from metal complexes. More specifically, the method involves applying an amorphous film of a metal complex to a substrate. The metal complexes have a metal and a photo-degradable ligand. A preferred ligand is acac or alkyl-acac, especially in combination with acetate ligands. These films, upon, for example, thermal, photochemical or electron beam irradiation may be converted to the metal or its oxides. By using either directed light or electron beams, this may lead to a patterned metal or metal oxide film in a single step. Low temperature baking may be used to remove residual organics from the deposited film. If silica is the metal, the deposited film has excellent smoothness and dielectric properties.

Description

Photolytic conversion process for forming embossed amorphous films

Technical Field

The present invention relates to methods of depositing metal or metal oxide films using metal complexes. In particular, the invention relates to the use of silicon-containing complexes to deposit embossed films of silica-silica dioxide. Such films are useful in a variety of fields including, but not limited to, microelectronics manufacturing.

Background

Thin film deposition using non-vacuum techniques typically includes sol-gel or metalorganic or photochemical metalorganic deposition. Inorganic films are typically deposited by chemical or physical vapor deposition, although sol-gel or metal organic deposition methods are also used in some cases. Sol-gel or metalorganic deposition processes require the formation of a precursor film. These films are then heated to remove the organic components, leaving behind a metal film or more commonly a metal oxide film. The photochemical deposition method differs from the two methods described above in that the reaction for removing the organic component is actinically activated. Since none of these methods are capable of forming embossed structures commonly used in microelectronic device or circuit construction, they must be used with other methods to form patterns on thin films of materials.

Hybrid processes typically use light as an energy source, where the light used initiates a thermal reaction rather than a photochemical reaction. These methods have the disadvantage that they do not directly produce an embossed film but rather lead to an indiscriminate deposition of the film.

The above deposition methods have other disadvantages in that they require the use of expensive equipment, and many of them require high temperature processing.

Due to problems associated with contamination that may occur to clean room equipment, there is a need for a chemical that can be used for different deposition processes. Furthermore, the use of only one chemical in different deposition processes reduces the development costs of the product for the supplier.

Metals, such as copper, may be used as conductors for electronic circuits. Other metal oxides, such as copper oxide, are semiconductors and have been used as conductors in electronic circuits. Therefore, it is important to develop methods for achieving metal deposition and patterned deposition of metals or their oxides on a variety of substrates.

U.S. patent No. 5,534,312 to Hill et al, which is incorporated herein by reference, describes a method for the systematic deposition of various metals and metal oxides using photochemical deposition. It will be appreciated that the approach discussed herein is a substantial improvement over the prior art. The present invention provides novel metal complexes or precursors useful for thermal, electron beam, and photochemical embossing of copper-containing materials, and methods for the deposition of these complexes.

Precursors used in the prior art to deposit metal or metal oxide films, such as those shown below and described in U.S. Pat. No. 5,534,312, are believed to fragment under photolytic conditions, resulting in CO₂Loss of the catalyst. This fragmentation leaves free metal atoms.

Complexes described by Chung et al, j.chem.soc., Dalton trans, 1997, pages 2825-29, incorporated herein by reference, also contain a pair of metal atoms bonded to a bidentate organic ligand. The most common form of these complexes has the following formula:

in the above formulae, the positions of each available substitution to optimize physical and chemical properties are shown. The organic ligand structures of these complexes do not exhibit significant cleavable sites under photolytic conditions, for example. Thus, it is not clear that the complexes of the formula are suitable for photolytic deposition of metals or metal oxides. In fact, it is reasonably predictable that the photochemical reactivity is with the group X in the figure₁And X₂Is central. Indeed, published photochemistry for such complexes (Chung et al (1997) J. chem. Soc., Dalton Trans., 2825) led one of ordinary skill in the art to consider the society of photochemistryA stable copper (I) complex is produced. However, in amorphous films containing such complexes, copper metal is formed. Precursors of the forms shown above have been found to be useful for depositing films composed of metals (e.g., copper) or oxides thereof.

The dielectric layer plays a role in the manufacture and protection of individual semiconductor elements in a complete circuit (IC)Plays an important role. SiO 2₂Is one of the most important materials for these uses. For a description of The important properties of such dielectrics, see Balk, Peter, (Ed.) Material science monograph, 32.The Si — SiO₂System, elsevier, amsterdam, the netherlands, 1988. Due to their excellent dielectric constants (between about 3.1 and 4.1 for fused silica, according to G.V samonov (Ed.), The Oxide handbook. second Ed. IFI/plenum. New York, Washington, London, 204, 1992) and Si/SiO₂Good electronic properties at the interface, SiO₂Has wide application space asan insulator.

In the complete circuit, high quality Si/SiO₂The fabrication of the interface is critical to the performance of many electronic devices. Deposition methods that result in minimal substrate damage are therefore very important and of great interest. As a low temperature deposition method, sol-gel is a generally preferred method. However, in this deposition method, Si and Si/SiO₂The quality of the interface is not such that it is used for a complete circuit without further processing.

The films can be easily deposited by sol-gel methods using techniques such as dip coating, spin coating, spray coating, and the like. The first two methods have been successfully used to fabricate thin film layers with optical properties. For details of the process, see Sol-Gel Science and Technology, 8, 1083, 1997. One of the most attractive features of the sol-gel process is that the thin film can be prepared without the use of expensive equipment and high temperature processing. Surfaces from a few millimeters to several meters can be coated (by dip coating). Despite many advantages, sol-gel-process produced films contain micron-sized pores and organic impurities in their structure, and thus are practically as described by Oh, Junrok; imai, Hiroaki; and hirshima, Hiroshi; non-crystalline Solid, 241, 91, 1998, requires heat treatment above 400 ℃ to obtain a compact, uniform structure.

Deposition of high quality SiO for optical applications₂In the case of thin films, heat treatment is of considerable importance. Typically after heating at 500 ℃ for 1 hour, the film is still porous, but after heat treatment at 1000 ℃ for 5 minutes, a completely tight film is observed. The Si-O bond is cleaved by water molecules, resulting in strained SiO₂The rearrangement of the network, and thus the densification of the film, can be represented by the following sequential reactions:

(tensioned) (stable)

Thus, this heat treatment can produce a uniform and compact structure from the standpoint of Oh et al. Imai, h.; moritomo, h.; tominaga, a.; and hirshima, h.j.sol-gelsci.technology, 10, 45, 1997, proposed that water molecules act as catalysts in the investigation of the tightness of silica membranes exposed to water vapor. Sol-gel processes require process improvements, especially in terms of thickness control, which is a very important issue for optical coatings.

Other methods of preparing SiO have been developed₂A method of making a thin film. These methods include sputtering and Chemical Vapor Deposition (CVD) as described in jpn.j.appl.phys, 36, 1922, 1997. These methods have the disadvantage that the substrate reaches a high temperature sufficient to cause surface diffusion. These methods also require high vacuum conditions, which increases the cost of deposition.

Atmospheric pressure CVD has attracted attention because it produces good quality SiO at low deposition temperatures (350-₂And (3) a membrane. From (SiH)₄+O₂) In N₂The mixture in the carrier gas is deposited to form a film. Martin, j.g.; o' Neal, h.e., Ring, M.A; roberts, d.a.; and the use of Tetraethoxysilane (TEOS) as a source is described in Hochberg, a.k., j.electrochem.soc.142, 3873, 1995A method for preparing the material. TEOS has gained widespread interest because it forms a good quality thin film with high dielectric breakdown strength. Furthermore, as Wrobel, a.m.; Walkiewicz-Pretrzykowska, A.; wickramanayaka, s.; and Hatanaka, y, as described in j.electrochem soc.145, 2866, 1998, which has a conformal coverage superior to SiH₄。

SiO₂A new method of selective deposition on silicon uses a hydrogen passivated silicon surface. The local oxidation is performed by using STM, AFM, or electron beam lithography. Of course, these methods are not suitable for large area embossing due to the long writing time.

Photolithography using photoresist is another method of depositing an embossed layer of silica. This, of course, includes many additional steps of depositing and removing the photoresist.

There is a need for a method of depositing SiO with sufficient dielectric properties in a few steps at room temperature₂A method of making a thin film. There is also a need for a method of forming patterned metal and dielectric layers with a minimum of processing steps. There is also a need for a method of forming an amorphous dielectric having a particular thickness. There is also a need for a method of adding additives in small steps to alter the dielectric constant or catalytic activity or other properties of a dielectric, wherein the process can be carried out at near room temperature.

Disclosure of Invention

One aspect of the invention relates to a photoresist-free method of depositing a film composed of a metal, such as copper or an oxide thereof, with a metal complex. More specifically, the method comprises plating an amorphous film of the metal complex onto a substrate. The precursor material is applied to a substrate and then treated with energy, advantageously using a method for forming a conductive pattern on the substrate. Alternatively, the metal layer may be patterned and then formed by any other mechanism known in the art.

A second aspect of the invention is directed to a photoresist-free method of depositing a dielectric film. Advantageously, the film is a dielectric film having predetermined dielectric properties that vary with the end use of the film.

A particularly preferred dielectric is Si/SiOH. The present invention describes the use of metal complexes to form amorphous films that can be converted to silica and/or silicon dioxide thin films by a variety of methods. These films can be used to prepare embossed films of silica-containing materials by photolithography. The metal complex, i.e., the silicon-containing complex-containing film, may be irradiated in an embossed manner to produce lithographic deposition by photochemical metalorganic deposition.

The dielectric film may contain native metal oxides and/or hydroxides, wherein the native metal is silicon, titanium, zirconium, tantalum, barium, strontium, hafnium or mixtures thereof, and the native metal is preferably silicon, for example a silicon oxide such as silica. Preferred dielectric films contain silica. Preferred dielectric layers contain silicon such that at least half (e.g., at least 60%) of the metal atoms therein are silicon. The dielectric film may optionally contain: 1) doped silicon oxides, such as fluorinated silicon oxides; 2) dielectric property-modifying additives for modifying the electron affinity and thus the height of the electron and hole barriers, such as oxides of calcium, strontium, aluminium, lanthanum or scandium, or mixtures of oxides thereof, in amounts known to the person skilled in the art, for example between 0.01 and 0.9 mol, preferably between 0.1 and 0.6 mol, of dielectric property-modifying additives per mole of native metal oxide and/or hydroxide forming the dielectric layer; and/or 3) a surface active component comprising, for example, a catalytic species, such as gold, platinum, palladium, ruthenium, rhodium, iridium, gold, copper, silver, or mixtures thereof, wherein the catalytic species may be in metallic form and/or in oxide form, wherein the catalytic species is distributed in the dielectric film or in an outer layer of the dielectric film or on the dielectric film in an amount insufficient to cause substantial leakage through the dielectric layer but is capable of modifying the exposed surface to provide a catalytic template for formation of a next layer deposited thereon (e.g., an amount of catalyst less than about 50 mole percent compared to moles of the native metal, such as between about 0.01 mole percent and about 25 mole percent, such as 15 mole percent compared to the native metal in the dielectric film). Higher concentrations in this range are generally useful when the dielectric film containing a lower concentration of catalytic species in the dielectric film is covered by a dielectric film containing a higher concentration of catalytic species. The other surface active component may be a viscosity enhancing component known to those of ordinary skill in the art and depends on the properties of the dielectric layer and the properties of the next layer. The dielectric film can be made to a predetermined thickness, wherein the thickness can be the same or different on the substrate. The thickness may range from a monolayer or sub-monolayer of the thickness of the catalytic and/or adhesion promoting components typically used for deposition to a thickness on the order of microns or greater. The composition of the dielectric layer can vary between various proportions of the substrate, wherein one of ordinary skill in the art can adjust the properties of the dielectric layer to achieve properties suitable for a desired application without undue experimentation. Advantageously, each of these deposited dielectric films is an amorphous film. The dielectric film may be heat treated, optionally in the presence of optional ingredients that may alter the properties of the dielectric film, such as oxygen or water vapor or nitrogen or fluorine.

The present invention may be used to form a variety of dielectric layers. Typically, silicon dioxide has a dielectric constant of about 4, while high-k films have adielectric constant greater than about 10. The high-k material comprises titanium oxide (TiO)₂) Zirconium oxide (ZrO)₂) Tantalum oxide (Ta)₂O₅) Titanium oxide and barium strontium titanate (Ba, Sr) TiO₃. Other group IV and V metal oxides, such as hafnium oxide, may be used. One common problem associated with the above-mentioned high-k dielectrics is that they form crystalline structures under normal manufacturing conditions. For example, metal oxide high-k dielectric films of zirconium (Zr) or hafnium (Hf) oxides or mixtures thereof, optionally doped with about 10% to about 40% divalent metal (e.g., calcium (Ca) and/or strontium (Sr)) and/or trivalent metal (e.g., aluminum (Al), scandium (Sc), and/or lanthanum (La)) oxides to alter electron affinities and thereby alter electron and hole barrier heights, can be readily formed by the methods of the present invention. As a preferred dielectric, these films contain Zr and/or Hf, a doping metal and oxygen, whereby a film having a high dielectric constant and good barrier properties is formed by annealing at a temperature of about 400 to 900 ℃.

Preferably, the dielectric layer formed according to the present invention is amorphous to reduce leakage caused by grain boundaries.

In one embodiment, a dielectric precursor material, such as a silicon-containing precursor material, is applied to a substrate, such as by spin coating, on a surface. Any coating method known in the art is feasible. The dielectric matrix material may include one or more precursors containing a native metal, one or more surface active metal precursors, and/or one or more additive metal precursors for modifying dielectric properties. The dielectric precursor material, e.g., silicon-containing precursor material, is then converted by photolysis (optionally assisted by thermal degradation in certain embodiments) using various available energies. Photolysis of such compounds results in the production of, for example, silicon dioxide in the exposed and converted regions. The method can be used to pattern thin layers of silicon dioxide for a variety of applications. These fields of application include dielectric embossing for the semiconductor industry.

In a very broad aspect, the invention consists in one particular embodiment of a composition generally of formula M_fL_gX_hWherein the terms f, g and h denote mole fractions and are usually integers, and:

-M is a primary metal selected from silicon, titanium, zirconium, tantalum, barium, strontium, hafnium or mixtures thereof, in particular silicon;

l is a decomposable ligand containing a bond that is cleaved by a photon having a predetermined energy and each end is bonded to (or balanced with) a species that is bonded to the parent metal, e.g. of formula Y¹-Z¹R⁵ _a-Z¹R⁵ _a-Z¹R⁵ _a-Y¹-, in which Y¹Bonded to the parent metal and independently N, O or S, preferably O, Z¹Independently N, O or C, wherein in a preferred embodiment at least two Z' s¹Is C and the remaining Z¹Is C or N, each R⁵Independently selected from a) H, b) OH, c) O, d) containing one to about fourteen carbon atomsRadicals of the subgroups include, for example, linear, branched or cyclic: alkyl (e.g. C)_nH_m) Alkoxy (e.g. OCC)_nH_m) And/or acidic moieties (e.g., OOCC)_nH_m) In which radicals containing from one to about fourteen carbon atoms may optionally be partially or completely substituted by halogen, preferably fluoride, and/or substituted thereon or contain oxygen, nitrogen or sulfur, e) radicals containing from one to about eight nitrogen atoms, including, for example, linear, branched or cyclic amines, alkoxyamines, amines containing acidic moieties, N₃Cyanate (e.g. CN and NCO), nitrate/nitrite (e.g. NO)₃And NO₂) Nitroso, NCO and/or F) halides, including for example Cl, Br, I and F. The term "a" denotes a linkage to a particular Z¹The number of R groups on an atom, i.e., typically zero for oxygen, one for nitrogen, two for carbon, although the number "a" may vary.

-X is an anion independently selected from the following groups: a) h, b) OH, C) O, d) groups containing one to about fourteen carbon atoms (e.g., one to four carbon atoms), including, for example, straight, branched, or cyclic, and may include alkyl and aryl groups (examples include, for example, alkenyl groups and may be substituted with C_nH_mRepresents), alkoxy (e.g. OCC)_nH_m) And/or acidic moieties (e.g., OOCC)_nH_m) Wherein the group containing one to about fourteen carbon atoms may optionally be partially or fully substituted by and/or substituted on halogen (preferably fluoride) or contain oxygen and/or nitrogen, less preferably other elements such as sulfur, and e) a group containing one to about eight nitrogen atoms, preferably three or less nitrogen atoms, including for example linear, branched or cyclic amines, alkoxyamines, amines containing acidic moieties, N₃Cyanate (e.g. CN and NCO), nitrate/nitrite (e.g. NO)₃And NO₂) Nitroso, NCO and/or F) halides, including for example Cl, Br, I and F.

Preferably, for formula M_fL_gX_hF is equal to 1, g is equal to 1 to 3, and h is equal to 1 to 3. Preferably, if there are a plurality ofL-portions, then at least two L-portions are different from each other. In a particular embodiment of this aspect of the invention, "f" is 1 and "g" is 2 or greater, at least two L moieties being different from each other. Preferred L moieties include alkoxy OCC_nH_mOr acidic moieties O₂CC_nH_mWherein the alkoxy or acidic moiety may be substituted or unsubstituted. In a preferred embodiment of this aspect of the invention, the term "h" is 2 or greater and the moieties X are different from each other. In another preferred embodiment of this aspect of the invention, the term "h" is 2 or greater and the moiety X comprises an alkoxy group OCC_nH_mOr acidic moieties O₂CC_nH_mWherein the alkoxy or acidic moiety may be substituted or unsubstituted.

In a particular embodiment of this main aspect of the invention, the matrix material also contains a compound of formula M'_fL_gX_hWherein the terms L, X, f, g, and h are as described above, and M' is selected from the group consisting of surface active precursor materials including catalytic species known to those of ordinary skill in the art to provide catalytic sites for the formation of additional layers, and including, for example, gold, platinum, palladium, ruthenium, rhodium, iridium, gold, copper, silver, iron, or mixtures thereof. The amount of catalytic surface active precursor material added to the precursor material may be an amount insufficient to cause substantial leakage through the dielectric layer but capable of modifying the exposed surface to provide a catalytic template for the formation of the next layer deposited thereon, i.e. the amount of catalyst metal is less than about 50 mole% compared to the moles of native metal, e.g. the catalyst metal is between about 0.01 mole% and about 25 mole%, e.g. about 15 mole%, per mole of native metal oxide and/or hydroxide forming the dielectric layer). If the surface active precursor material is a precursor for the deposition of an adhesion promoting element, the amount of the precursor for the deposition of the adhesion promoting element may be from about 0.001 mole% to about 25 mole%, for example about 15 mole%, of adhesion promoting metal per mole of virgin metal oxide or hydroxide. Generally, substantially pure sub-surfactants can be deposited on the surface of the dielectric filmAn atomic layer or a monolayer.

In another embodiment of this broad aspect of the invention, the precursor material further comprises a compound of formula M ″_fL_gX_hWherein the terms L, X, f, g and h are as described above, and M "is selected from divalent and/or trivalent metals known to those of ordinary skill in the art to modify the properties of the dielectric film, such as calcium, strontium, aluminum, lanthanum or scandium, or mixtures thereof. The dielectric property modifying precursor is added to the precursor material in an amount well known to those skilled in the art, for example, between 0.01 and 0.9 moles, preferably between 0.1 and 0.6 moles, of dielectric property modifying additive per mole of native metal oxide and/or hydroxide forming the dielectric layer.

Of course, the precursors of the present invention may include dielectric property modifying precursors and surface active precursors including catalytic and/or adhesion promoting materials.

In one embodiment of the present invention, the parent complex of one embodiment of the present invention is generally of the formula M_fL¹ _gX¹ _hWherein the terms f, g and h denote mole fractions and are usually integers, and:

-M is a primary metal selected from silicon, titanium, zirconium, tantalum, barium, strontium, hafnium or mixtures thereof, in particular silicon;

-L¹is a decomposable ligand having each end bound to (or in equilibrium with) a species having each end bound to the parent metal, e.g. of the formula-O-CR⁵ _a-CR⁵ _a-CR¹⁵ _a-O-, wherein preferably both oxygens are bonded to the parent metal, each R⁵The groups are independently selected from a) H, b) OH, c) O, d) groups containing one to about fourteen carbon atoms, including for example, straight, branched, or cyclic: alkyl (e.g. C)_nH_m) Alkoxy (e.g. OCC)_nH_m) And/or acidic moieties (e.g., OOCC)_nH_m) Wherein the groups containing one to about fourteen carbon atoms may optionally be partially or fully halogenatedElements, preferably fluorides, substituted and/or substituted thereon or containing 0 to 8 oxygen, nitrogen or sulfur atoms therein, e) groups containing one to about eight nitrogen atoms, including, for example, straight, branched or cyclic amines, alkoxyamines, amines containing acidic moieties, cyanates (e.g. CN and NCO), nitrates/nitrites (e.g. NO)₃And NO₂) Nitroso, NCO and/or F) halides, including for example Cl, Br, I and F. The term "a" denotes R attached to a carbon atom⁵The number of groups, and the number "a" may be different for each carbon atom.

-X¹Is an anion independently selected from the following groups: a) h, b) OH, C) O, d) groups containing one to about fourteen carbon atoms (e.g., one to four carbon atoms), including, for example, straight, branched, or cyclic, and may include alkyl and aryl groups (e.g., C)_nH_m) Alkoxy (e.g. OCC)_nH_m) And/or acidic moieties (e.g., OOCC)_nH_m) Wherein the group containing one to about fourteen carbon atoms may optionally be partially or fully substituted by and/or substituted on halogen (preferably fluoride) or contain oxygen and/or nitrogen, less preferably other elements such as sulfur, and e) a group containing one to about eight nitrogen atoms, preferably three or less nitrogen atoms, including for example linear, branched or cyclic amines, alkoxyamines, amines containing acidic moieties, N₃Cyanate (e.g. CN and NCO), nitrate/nitrite (e.g. NO)₃And NO₂) Nitroso, NCO and/or F) halides, including for example Cl, Br, I and F.

In a particular embodiment of this aspect of the invention, "f" is 1 and "g" is 2 or greater, at least one X¹Preferably an alkyl group C_nH_m(e.g., -C (CH)₃)₃or-CH₃) Alkoxy radical OCC_nH_m(e.g. -OCH)₂CH₃、-OCH(CH₃)₂、OCH₂C(CH₃)₃and-OCH₃) Or acidic moieties O₂CC_nH_m(e.g., -O)₂CCH₃、-O₂CC(CH₃)₃、O₂CH(CH₃)₂and-O₂CH), wherein the alkyl, alkoxy or acidic moiety may be substituted or unsubstituted. In a preferred embodiment of this aspect of the invention, the term "g" is 2 or greater, X¹The portions are different from each other.

In a particular embodiment of the invention, the matrix material also contains a compound of formula M'_fL_gX_hWherein the terms L, X, f, g, and h are as described above, and M' is selected from the group consisting of surface active precursor materials including catalytic species known to those of ordinary skill in the art to provide catalytic sites for the formation of additional layers, and including, for example, gold, platinum, palladium, ruthenium, rhodium, iridium, gold, copper, silver, iron, or mixtures thereof. The amount of catalytic surface active precursor material added to the precursor material may be an amount insufficient to cause substantial leakage through the dielectric layer but capable of modifying the exposed surface to provide a catalytic template for the formation of the next layer deposited thereon, i.e. the amount of catalyst metal is less than about 50 mole% compared to the moles of native metal, e.g. the catalyst metal is between about 0.01 mole% and about 25 mole%, e.g. about 15 mole%, per mole of native metal oxide and/or hydroxide forming the dielectric layer).

In one embodiment of the invention, the precursor material further comprises a compound of formula M ″_fL_gX_hWherein the terms L, X, f, g and h are as described above, and M "is selected from divalent and/or trivalent metals known to those of ordinary skill in the art to modify the properties of the dielectric film, such as calcium, strontium, aluminum, lanthanum or scandium, or mixtures thereof. The dielectric property modifying precursor is added to the precursor material in an amount well known to those skilled in the art, for example, between 0.01 and 0.9 moles, preferably between 0.1 and 0.6 moles, of dielectric property modifying additive per mole of native metal oxide and/or hydroxide forming the dielectric layer.

To form a multi-component film, a precursor material containing a single metal (i.e., silicon, hafnium, zirconium, and/or aluminum, etc.), optionally a dielectric property altering metal (e.g., calcium, strontium, aluminum, lanthanum, or scandium), and optionally an adhesion promoting metal and/or a catalytic metal, is mixed into the precursor solution in the desired amounts. Each metal requires a different ligand to have the solubility and photoreactivity needed to effectively form the substrate.

The precursor is coated on a substrate, converted (or partially converted), developed by removing unconverted material, and heat treated as needed. If different complexes have different activation energies, delamination can occur in the film if the energy source of the conversion energy is adjusted to take advantage of the difference. Similarly, lateral variations are likely to occur in the same manner. For example, if a precursor containing a catalytic metal requires a higher activation energy to be photoreactive than, for example, the original dielectric metal, then the deposition of the catalytic metal in the film can be controlled by controlling the activation energy to be within a desired range.

In one embodiment, the complexes of the present invention are generally of the formula M_fL² _gX² _hWherein f, g and h are integers:

m is a native metal having an oxide with suitable dielectric properties, preferably silicon, titanium, and/or zirconium, but also tantalum, barium, strontium, hafnium or mixtures thereof, especially silicon.

L²Is an β -dione ligand in which preferably both oxygens are bonded to the native metal, β -dione ligand in which the various carbons and/or nitrogens are independently substituted by a) H, b) OH, C) O, d) groups containing one to about fourteen carbon atoms including, for example, straight, branched or cyclic alkyl (e.g. C)_nH_m) Alkoxy (e.g. OCC)_nH_m) And/or acidic moieties (e.g., OOCC)_nH_m) In which radicals containing from one to about fourteen carbon atoms may optionally be partially or completely substituted by halogen, preferably fluoride, and/or substituted thereon or contain from 0 to 8 oxygen, nitrogen or sulfur atoms, e) radicals containing from one to about eight nitrogen atoms, including, for example, linear, branched or cyclic amines, alkoxyamines, amines containing acidic moieties, cyanic acidSalts (e.g. CN and NCO), nitrates/nitrites (e.g. NO)₃And NO₂) Nitroso, NCO and/or F) halides, including for example Cl, Br, I and F.

In one embodiment, L²Is of the formula (R)₂NCR₂'CO) wherein R and R' are independently selected from H, OH, O, C_nH_m、OC_nH_m、OC_nH_mA_xB_y、C_nH_mA_xB_yAnd halogen, wherein A and B are independently selected from main group elements, and f, g, h, n, m, x and y represent integers.

In one embodiment, L²Is a ligand comprising a substituted or unsubstituted aminoalkane-2-alkoxide, such as mu-aminopropan-2-alkoxide, diethylaminoethyl-2-alkoxide, diethylaminobutane-2-alkoxide, acetylacetonate, alkyl acetylacetonate or a mixture thereof.

X²Is a) H, b) OH, c) a group containing one to about fourteen carbon atoms (e.g. one to four carbon atoms), including for example straight, branched or cyclic, and may include alkoxy groups (e.g. OCC)_nH_m) And/or acidic moieties (e.g., OOCC)_nH_m) Wherein the radicals containing from one to about fourteen carbon atoms may optionally be partially or fully substituted by halogen, preferably fluoride, and/or substituted thereon or contain oxygen and/or nitrogen, and d) contain from one to as large asGroups of about eight nitrogen atoms, preferably three or less nitrogen atoms, include, for example, linear, branched or cyclic amines, alkoxyamines, amines containing acidic moieties, N₃Cyanate (e.g. CN and NCO), nitrate/nitrite (e.g. NO)₃And NO₂) Nitroso groups and NCO, wherein the bond to the parent metal is preferably to a nitrogen atom, and/or F) halides, including for example Cl, Br, I and F. X²Can be independently selected from N₃、NCO、NO₃、NO₂Cl, Br, I, F, CN, OH, H, R, OCR and O₂C-R, wherein R is C₁To C₁₄Alkyl, aryl or heterocyclic.

In other embodiments, the surfactant precursor and/or the dielectric constant modifying precursor may be mixed with the dielectric film precursor material to modify the properties of the dielectric layer as described in other embodiments.

In many embodiments, the precursor material is applied to the substrate as a liquid. In order to obtain very thin films, it is often necessary to dissolve these parent materials in a solvent. The solvent may be substantially removed during the step of plating the precursor onto the substrate. Beneficially, certain solvents may be maintained for a sufficient period of time to impart desired properties to the dielectric layer, including, but not limited to, porosity, shrinkage and cracking resistance, and the like. It has been found that amines, particularly alkanolamines, can have a beneficial effect on film shrinkage and cracking during drying and curing. Monoethanolamine and diethanolamine have proven effective, although other alkanolamines can also provide beneficial properties, depending on the ligand attached to the various parent materials.

These films, upon thermal, photochemical or electron beam stimulation, can be converted to metals or their oxides. It is possible to form embossed metal or metal oxide films in a single step by using directed light or electron beams.

The present invention includes a method of making an embossed dielectric film on a substrate, comprising: depositing a precursor film comprising a solvent and a metal precursor complex having the formula,

this formula does not reflect the true bonding to the metal, since both oxygens in the ligand can be bonded to the metal M or is, for example, a formula containing more R groups, such as the two shown below, as follows:

wherein n is an integer of 1 to 4, R₁Independently selectedfrom H, OH or groups containing 1 to 14 carbon atoms including, for example, alkyl, aryl, heterocyclic, amine, alkoxy,p is an integer of 0 to 4, R₂Independently selected from a) H, b) OH, c) groups containing one to about fourteen carbon atoms (e.g. one to four carbon atoms), including for example straight, branched or cyclic groups, and may include alkoxy groups (e.g. OCC)_nH_m) And/or acidic moieties (e.g., -OOCC)_nH_m) Wherein the radicals containing from one to about fourteen carbon atoms may optionally be partially or fully substituted by halogen (preferably fluoride) and/or substituted thereon or contain oxygen and/or nitrogen therein, d) radicals containing from one to about eight nitrogen atoms, preferably three or less nitrogen atoms, including for example substituted or unsubstituted linear, branched or cyclic amines, alkoxyamines, amines containing acidic moieties, N₃Cyanate (e.g. CN and NCO), nitrate/nitrite (e.g. NO)₃And NO₂) Nitroso and NCO, wherein the bond to the parent metal is preferably a nitrogen atom, and/or F) halides, including for example Cl, Br, I and F, wherein R is preferred₂Is a diketone such as acetylacetone.

Exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, in an amount sufficient to cause the ligand to disassociate from the molecules of the precursor complex, such that the exposed portion of the precursor film is insoluble in the solvent and loses carbon from the exposed film; removing the unexposed mother film; the film is heated to a temperature of from about 150 c to about 350 c for a time sufficient to remove substantially all of the carbon from the film, thereby forming an amorphous dielectric film comprising a metal oxide, metal hydroxide, or mixture thereof. As may be recognized by one of ordinary skill in the art.

The method may further comprise the steps of: at least half of the solvent is removed from the film prior to exposing the film to an amount of electromagnetic radiation, heat, ion beam, electron beam, or a combination thereof sufficient to remove a sufficient number of n ligands.

In a preferred embodiment of the invention, M is Si, n is 2, p is 1 or 2, and the atmosphere over the film contains oxygen. In another preferred embodiment, M is Si, n is 2, p is 1 or 2, and the atmosphere over the film contains water vapor when the film is heated to a temperature of from about 150 ℃ to about 300 ℃ for a time sufficient to remove substantially all of the carbon from the film.

In another embodiment, the precursor film comprises a plurality of metal precursors, such that there are a plurality of metal oxides/hydroxides in the dielectric film. The metals added are also usually in the form of oxides and/or hydroxides. This includes the metal used to dope the dielectric layer.

In a very preferred embodiment, R₁Is selected from CH₃And C (CH)₃)₃。

The exposure comprises exposure to electromagnetic energy through a mask or comprises exposing the precursor film to a directed beam of electromagnetic radiation, heat, an ion beam, an electron beam, wherein the beam has a size of about 50 μm or less, preferably about 10 μm or less, more preferably about 2 μm or less, thereby forming a dielectric pattern.

In one embodiment, the film is heated to between about 150 ℃ and about 250 ℃ for a time period of about 10 minutes to about 10 hours.

In one embodiment, R₂Including- (OCO) -R₃Wherein R is₃Is C₁To C₉Alkyl, aryl or heterocyclic.

In an embodiment of the high-k dielectric film, the dielectric film is an amorphous high-k dielectric film having a dielectric constant of at least 5, M is Ti, Zr, Ta, Hf, or mixtures thereof, and the precursor film further comprises Ca, Sr, Al, Sc, La, or mixtures thereof in a molar ratio to the moles of M of about 0.1 to about 0.6.

The invention also includes a method of making an embossed dielectric film on a substrate comprising depositing a composition comprising a solvent and having the formula M on the substrate_fL_gX_hWherein M is selected from Si, Ti, Zr, Ta, Ba, Sr, Hf or mixtures thereof, and L is a metal precursor complex of the formula (R)₂NCR₂' CO), R- (CO) ═ CH- (CO) -R ' ligands or mixtures thereof, wherein R and R ' are independently selected from H, C_nH_mAnd C_nH_mA_xB_yWherein A andb is independently selected from main group elements, and f, g, h, n, m, X and y represent integers, wherein X is independently selected from O₂CCH₃、N₃、NCO、NO₃、NO₂Cl, Br, I, CN, OH, H and CH₃An anion of (a); exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, such that the exposed portion of the precursor film is insoluble in the solvent and loses carbon as a result of the exposure of the film; removing the unexposed precursor film from the substrate; the film is heated at a temperature and for a time sufficient to remove substantially all of the carbon from the film, thereby forming an amorphous dielectric film comprising a metal oxide, a metal hydroxide, or a mixture thereof. In the case of this method, it is preferred that,in a preferred embodiment M is Si, f is 1, L is 1 or 2, and B is 1 to 3, wherein the atmosphere above the film during heating contains oxygen. In another embodiment, where M is Si, the atmosphere above the film contains water vapor when the film is heated to a temperature of about 150 ℃ to about 300 ℃ for a time sufficient to remove substantially all of the carbon from the film. In another embodiment, the precursor film comprises a plurality of metal precursors, such that there are a plurality of metal oxides/hydroxides in the dielectric film. Of course, in a preferred embodiment, R and R' are independently selected from CH₃And C (CH)₃)₃。

The invention also includes a method of making an embossed dielectric film on a substrate comprising depositing a composition comprising a solvent and having the formula M on the substrate_fL_gX_hWherein M is selected from the group consisting of Si, Ti, Zr, Ta, Ba, Sr, Hf, or mixtures thereof, L is a ligand comprising mu-aminopropyl-2-alkoxide, diethylaminoethyl-2-alkoxide, diethylaminobutyl-2-alkoxide, acetylacetonate, alkyl acetylacetonate, or mixtures thereof, and X is independently selected from the group consisting of N₃、NCO、NO₃、NO₂Cl, Br, I, CN, OH, H, R, OCR and O₂C-R, wherein R is C partially or fully substituted by halogen, especially fluoride₁To C₁₄Alkyl, aryl or heterocycle, f, g and h represent integers; removing at least a portion of the solvent from the precursor film;exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, thereby converting the portion of the precursor film such that the exposed portion of the precursor film is insoluble in the solvent, wherein carbon is lost as a result of exposing the film; removing the unexposed precursor film from the substrate; the film is heated at a temperature and for a time sufficient to remove substantially all of the carbon from the film, thereby forming an amorphous dielectric film comprising a metal oxide, a metal hydroxide, or a mixture thereof.

In this method, the step of removing the solvent from the film comprises exposing the film to a temperature of from about 80 ℃ to about 200 ℃, wherein the temperature does not cause significant conversion of the precursor, followed by exposing the film to an amount of electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof sufficient to remove a sufficient number of the n-ligands. In a preferred embodiment, M is Si and the atmosphere above the film contains oxygen, water vapor or a mixture thereof when the film is heated to remove substantially all of the carbon in the film. The exposure process and subsequent removal of unconverted precursor material is preferably patterned by, for example, solvent stripping. One mechanism for achieving this is that the exposure pattern includes exposure to electromagnetic energy through a mask, thereby forming a dielectric pattern. Alternatively, the exposing may also comprise exposing the precursor film to a directed beam of electromagnetic radiation, heat, an ion beam, or an electron beam, thereby forming the dielectric pattern. Low temperature heating is beneficial, so in a preferred embodiment, the film is heated to between about 150 ℃ to about 250 ℃, with a time period of about 10 minutes to about 10 hours.

In an embodiment of the high-k dielectric film, M is Ti, Zr, Ta, Hf, or a mixture thereof, wherein the dielectric film formed is an amorphous high-k dielectric film having a dielectric constant of at least 5, and the precursor film further comprises Ca, Sr, Al, Sc, La, or a mixture thereof in a molar ratio to M of about 0.1 to about 0.6.

Brief description of the drawings

FIG. 1 shows Si (acac)₂(acetate salt)₂The FTIR of (1) changes in a monotonic spectrum after 1, 5, 10, 35 minutes of photolysis.

FIG. 2 shows Si (O)₂CCH₃)₂(tbuacac)₂The FTIR of (a) shows monotonic spectral changes during photolysis at 254nm for 0, 1 and 2 minutes and subsequent heating at 400 ℃ for 10 hours.

Figure 3 shows an optical image showing lines of silicon dioxide deposited on silicon. The lines are 50 μm long by 2 μm wide.

Detailed Description

The present invention describes methods of forming films using metal (e.g., copper and silicon) complexes that can be pyrolyzed, charged particle (e.g., electron beam), or photon activated to deposit a conductor (i.e., copper-containing film or embossed film) and a dielectric (i.e., silica Si/SiOH film or embossed film), respectively.

The first step is to provide a substrate. Typical thin films can be deposited on a variety of substrates. These include the use of simple salts (e.g. CaF)₂) To metal-to-semiconductor surfaces, including one or more of silicon, various metal conductors, dielectrics, and the like. The nature of the substrate is not critical to the process, although it may affect the precursor film deposition process and the solvent used for deposition (if used). The most common substrate is silicon, but is not limited thereto. These silicon substrates may be coated with other layers such as dielectric layers, photoresists or polyimides, metal oxides, thermal oxides, conductive materials, insulating materials, ferroelectric materials or other materials used in electronic device construction. These include single crystal wafers. A wide variety of substrates can be coated by this method, and the nature of the present invention is not limited to a particular substrate.

The next step is to provide a precursor.

For metal deposition, the precursor complexes of the invention are generally of the formula M_fL_gX_hWherein M is selected from Ti, V, Cr, Au, Mn, Fe, Co, Ni, Cu, Zn, Si, Sn, Li, Cu, Ti,na, K, Ba, Sr, Mo, Ru, Pd, Pt, Re, Ir and Os, wherein L is represented by the formula (R)₂NCR₂A ligand of 'CO), wherein R and R' are independently selected from H, C_nH_mAnd C_nH_mA_xB_yWherein A and B are independently selected from main group elements, and f, g, h, N, m, X and y represent integers, X is independently selected from N₃、NCO、NO₃、NO₂Cl, Br, I, CN, OH, H and CH₃The anion of (4).

One example of such parent complexes include dinuclear copper complexes and dinuclear silicon complexes containing suitable bidentate ligands. Suitable ligands include: mu-aminopropan-2-ol, diethylaminoethyl-2-ol, diethylaminobutane-2-ol, and the like. Relevant complexes are disclosed by Chung et al in j.chem.soc., Dalton trans, 1997, pages 2825-29. The chemical formula of such binuclear copper precursor complexes is generally: m₂(μ-R₂NCR′CO)₂(X)₂Wherein R and R' are independently selected from H, OH, O, C_nH_m、OCC_nH_m、OC_nH_mA_xB_y、C_nH_mA_xB_yWherein A and B are independently selected from main group elements, and N, m, X and y represent integers, X is independently selected from N₃、NCO、NO₃、NO₂、Cl、Br、I、F、CN、OH、H、C₁To C₁₄Alkyl (e.g. CH)₃)、C₁To C₁₄Alkoxy (e.g. OCH)₃) And/or an anion of an amine, alkanolamine or alkoxyamine containing from one to 14 carbon atoms.

Although the binuclear copper complex containing a bidentateligand is exemplified as the conductive copper layer in some examples, the present invention is not limited to the copper complex. Other suitable metals that may be used in the present invention include: ti, V, Cr, Au, Mn, Fe, Co, Ni, Cu, Zn, Si, Sn, Li, Na, K, Ba, Sr, Mo, Ru, Pd, Pt, Re, Ir, Os and similar metals, or mixtures thereof.

Specifically, the present invention may also use a metal composed of a high dielectric, in which the processing conditions are adjusted to form an oxide thereof. From this disclosure, one of ordinary skill in the art can determine the stoichiometry corresponding to the specific metal and generic ligand formulas provided above.

Presently, preferred metal complexes for depositing metals (e.g., copper) include Cu₂(μ-Et₂NCH₂CH₂O)₂(N₃)₂、Cu₂(μ-Et₂NCH₂CH₂O)₂(NCO)₂、Cu₂(μ-Et₂NCH₂CH₂O)₂(NO₂)₂。

For precipitated silica, both mono-and dinuclear silicon-containing complexes containing a variety of ligands suitable for use are preferred. Suitable ligands include, for example: μ -aminopropan-2-ol, diethylaminoethyl-2-ol, diethylaminobutyl-2-ol, acetylacetonate (acac), alkyl acetylacetonate (i.e. t-butyl acetylacetonate) and acetate in combination with acetylacetonate and/or alkyl acetylacetonate (e.g. t-butyl acetylacetonate). These ligands may of course be substituted thereon to alter the solubility, coverage or other characteristics of the complex.

The process of the invention facilitates the formation of a film from a precursor material on a substrate. The precursor contains molecules specifically designed for its ability to be uniformly coated on a substrate, resulting in a film with high optical and/or dielectric quality and/or photosensitivity. The identity of the parent molecule is an important variable-the present invention includes a plurality of metal complexes of the formula MaLb containing at least one metal ("M") (i.e., a is an integer of at least 1) and at least one suitable ligand ("L") (i.e., b is an integer of at least 1).

If multiple metals are used, all of the metal atoms may be the same, may be different atoms and/or have different valences, e.g., BanA or Fe (II) Fe (III), or some may be the same and others different atoms and/or have different valences, e.g., Ba₂Fe (II) Fe (III). In any case, the metal M may be an alkali or alkaline earth metal (e.g., Ba or Li), a transition metal (e.g., Cr or Ni), a main group metal (e.g., Al or Sn), an actinide (e.g., U or Th)). Preferably, each metal is independently selected from Li, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, Sr, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Ba, La, Pr, Sm, Eu, Hf, Ta, W, Re, Os, Ir, Pt, Au, Pb, Th, U, Sb, As, Ce and Mg. More preferably, the metal is selected such that the dielectric constant of the metal oxide film is at least about 3. Particularly preferred are Si, Ti, Zr, Ta, Ba, Sr, Hf or mixtures thereof.

If multiple ligands are used, all of the ligands may be the same, all may be different, or some may be the same and some other may be different. In any case, the ligand L is chosen so as to ensure that a substantially unconverted parent complex can be formed having the following properties:

1) it can be deposited as a stable or metastable amorphous film on a substrate,

2) upon absorption of energy, e.g., photons of a desired energy, the film can be converted into a different metal-containing material by a chemical reaction, an

3) Any by-products of the energy-induced chemical reaction should be scavenged, i.e., sufficiently volatile to be easily removed from the film.

To achieve the first two results, the complex should have low polarity and low intermolecular forces. Since organic groups generally have low intermolecular forces, ligands having organic groups at their periphery are often satisfactory in terms of the first two requirements. If the absorbed energy is light, the chemical reaction of step (3) is referred to as a light-induced reaction.

The deposited film of the substantially unconverted precursor is amorphous or at least substantially amorphous. Therefore, in order to prevent crystallization of the metal complex layer, the ligand L is preferably such that the complex is asymmetric. The complex is made asymmetric by using ligands that themselves have two or more stereoisomeric forms. For example. If L is racemic ethyl 2-hexanoate, the metal complex formed is asymmetric, since the complex has several different stereoisomeric forms. The size and shape of the organic portion of the ligand can be selected, for example, by substituting various moieties on the basis of the ligand, to obtain optimal film stability and to adjust the thickness of the film deposited by the selected film deposition method.

The stability of amorphous films associated with crystallization can also be enhanced by fabricating thin films of complexes with several different ligands attached to each metal atom. Such metal complexes have several isomeric forms. E.g. CH₃HNCH₂CH₂NHCH₃Reaction with a mixture of nickel (II) salt and KNCS produces an isomeric mixture. The chemical nature of these different isomers is not believed to be significantly different, however, the presence of several isomers in the film impairs the crystallization of the complex in the film.

The complex must also be stable, or at least metastable, in the sense that it does not decompose spontaneously rapidly under the processing conditions. The stability of a complex of a particular metal depends, for example, on the oxidation state of the metal in the complex. For example, Ni (0) complexes are considered unstable in air, whereas Ni (II) complexes are stable in air. Therefore, the method of depositing Ni-based thin films including the process step in air should preferentially select the Ni (ii) complex rather than the Ni (0) complex.

Similarly, Si is metastable in air and the processing steps that provide oxygen and/or water vapor to silica can provide a Si-OH or silicon oxide compound as an excellent dielectric.

Partial conversion and conversion results from chemical reactions in the film that convert the partially converted or converted regions into the desired conversion material. Ideally, at least one ligand should be active and attached to the complex via a bond that is cleaved when the complex is raised to an excited state due to the influence of the conversion process. Preferably, the reactive groups are separated from the complex in a photo-initiated photochemical reaction, more preferably by ultraviolet light as part of the conversion process and/or the conversion process. In order for the photochemical step in the process to be efficient, the intermediate product produced when the reactive groups are separated is very preferably unstable and spontaneously converted to the desired new materials and volatile by-products. A complex may contain one or more active ligands and advantageously, when one ligand reactive group is separated, the other ligand becomes unstable.

There are several mechanisms by which the appropriate photochemical reaction occurs. Some examples of suitable reaction mechanisms that may be operable, alone or in combination, in accordance with the present invention are as follows: (a) absorption of the photons can place the complex in a ligand-to-metal charge transfer excited state, wherein the metal-ligand bond in the metal complex is unstable, the bond breaks, and the remainder of the complex spontaneously decomposes; (b) absorption of the photons can place the complex in a metal-to-ligand charge transfer excited state, wherein the metal-ligand bond in the complex is unstable, the bond breaks, and the remainder of the complex spontaneously decomposes; (c) absorption of photons can cause the complex to be in a d-d excited state, wherein the metal-ligand bond in the complex is unstable, the bond breaks, and the remainder of the complex spontaneously decomposes; (d) absorption of photons can cause the complex to be in an intramolecular charge transfer excited state, wherein the metal-ligand bond in the complex is unstable, the bond is broken, and the rest of the complex spontaneously decomposes; (e) absorption of the photons can cause at least one ligand of the complex to be in a localized ligand excited state, the bond between the excited ligand and the complex being unstable, the bond breaking and the remainder of the complex spontaneously decomposing; (f) absorption of the photon may place the complex in an intramolecular charge transfer excited state such that at least one ligand of the complex is unstable and decomposes and then the remainder of the complex is unstable and spontaneously decomposes; (g) absorption of the photon may cause at least one ligand of the complex to be in a localized ligand excited state, wherein the excited ligand is unstable and decomposes, and then the remainder of the complex is unstable and spontaneously decomposes; and (h) absorption of the photon can place the complex in a metal-to-ligand charge transfer excited state, wherein at least one ligand in the complex is unstable and decomposes, and then the remainder of the complex is unstable and spontaneously decomposes. However, in a broad sense, the present invention is not to be construed as being limited to these reaction mechanisms.

Exemplary metalcomplexes and their metal and ligand components are described in U.S. Pat. No. 5,534,312, which is incorporated herein by reference in its entirety. Preferred metal complex precursors contain ligands meeting the above criteria. More preferably, these ligands are chosen from the group consisting of acetylacetonates (also known as "acac" or 2, 4-pentanedione) and their anions, substituted acetylacetonates, i.e.

And its anion, acetonylacetone (also known as 2, 5-hexanedione) and its anion, a substituted acetonylacetone, i.e.

And anions thereof, dialkyl dithiocarbamates i.e.

And anions thereof, carboxylic acids i.e

For example wherein R ═ CH₃(CH₂)₄Hexanoic acid, carboxylic acid esters of (i)

For example wherein R ═ CH₃(CH₂)₄Hexanoic acid esters, pyridines and/or substituted pyridines of

Azido (i.e. N)₃-, amines (e.g. RNH)₂) Diamines (e.g. H)₂NRNH₂) Arsine or arsine

Biarsine

Phosphine is

Diphosphines are

Aromatic hydrocarbons, i.e.

Hydroxy (i.e., OH-), alkoxy ligands (e.g., RO-), and ligands such as (C)₂H₅)₂NCH₂CH₂A ligand of O-, an alkyl ligand (e.g., R-), an aryl ligand, and mixtures thereof, wherein each of R, R ', R ", R '" and R ' "is independently selected from an organic group, preferably independently selected from C₁ToC₁₄Alkyl, alkenyl, aralkyl, and aralkenyl.

The term "alkyl" as used herein refers to a straight or branched hydrocarbon chain. The phrase straight or branched hydrocarbon chain as used herein refers to any substituted or unsubstituted acyclic carbon-containing compound, including alkanes, alkenes, and alkynes. Examples of the alkyl group include lower alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl or isohexyl; higher alkyl groups such as n-heptyl, n-octyl, isooctyl, nonyl, decyl, and the like; lower alkenyl, such as ethylene, propylene, propylyne, butene, butadiene, pentene, n-hexene, or isohexene; and higher alkenyl groups such as n-heptene, n-octene, isooctene, nonene, decene, and the like. Those of ordinary skill in the art are familiar with a variety of straight-chain (i.e., linear) and branched alkyl groups within the scope of the present invention. Furthermore, these alkyl groups may also contain various substituents in which one or more hydrogen atoms are substituted with a functional group or a chain functional group.

The term "alkenyl" as used herein refers to a straight or branched hydrocarbon chain wherein at least one carbon-carbon bond is a carbon-carbon double bond. The term "aralkyl" as used herein refers to an alkyl group terminally substituted with at least one aryl group (e.g., benzyl). The term "aralkenyl" as used herein, refers to an alkenyl group terminally substituted with at least one aryl group. The term "aryl" as used herein refers to a hydrocarbon ring having a conjugated double bond system, typically containing at least six pi electrons. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, anisyl, toluyl, xylyl, and the like.

The term "functional group" in the context of the present invention refers primarily to moieties with pendant and/or terminal functionality in the chain as understood by those of ordinary skill in the art. Mention may be made, as examples of functional groups in the chain, of ethers, esters, amides, carbamates and thio derivatives thereof, i.e. at least one oxygen atom is replaced by a sulfur atom. As examples of side and/or end functional groups, mention may be made of halogens, such as fluorine and chlorine, and hydrogen-containing groups, such as hydroxyl, amino, carboxyl, thio-, amido, isocyanate, cyano, epoxy and ethylenically unsaturated groups, such as allyl, acryloyl, methacryloyl, and maleate and maleimide groups.

To enhance the desired photochemical properties, including the tendency of the products of the photochemical reaction to decompose spontaneously thermally, ligands comprising and/or selected from one or more of the following groups may be used alone or in combination with the above ligands: oxy (i.e. O)₂-) and oxalic acid radical namely

Halides, hydrogen, hydrides (i.e., H-), dihydrides (i.e., H-₂) Hydroxy, cyano (i.e.CN-), carbonyl, nitro (i.e. NO)₂) Nitrite based (NO)₂-), nitrate esters (i.e., NO)₃) Nitric acid radical (i.e. NO)₃-), nitrosyl (i.e., NO), ethylene, acetylene (i.e., R.ident.R'), thiocyano (i.e., SCN-), isothiocyanato (i.e., NCS-), hydrate (i.e., H-)₂O), azido, carbonate (i.e., CO)₃-2), amines and thiocarbonyls, wherein R and R' are independently selected from organic groups, preferably independently selected from alkyl, alkenyl, aralkyl and aralkenyl. More preferably, each ligand is independently selected from the group consisting of acac, carboxylate, alkoxy, oxalate, azide, carbonyl, nitro, nitrate, amine, halogen and anions thereof.

In one embodiment, the precursor is used for dielectric and conductive layers, the metal complex precursor is selected from those containing at least one ligand selected from acac, carboxylic acid (carboxylato), alkoxy, azido, carbonyl, nitrate, amino, halogen, nitro, and mixtures thereof and at least one metal selected from Li, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, Sr, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Ba, La, Pr, Sm, Eu, Hf, Ta, W, Re, Os, Ir, Pt, Au, Pb, Th, U, Sb, As, Ce, and Mg, and mixtures thereof.

The precursor may be plated directly onto the substrate. Alternatively, and preferably, the precursor is dissolved in one or more solvents to form a precursor solution. This facilitates its application to the substrate by a variety of methods known to those of ordinary skill in the art, such as spin or spray application of the solution to the substrate. The solvent is selected based on several criteria, taken alone or in combination, including its ability to dissolve the precursor, its inertness relative to the precursor, its viscosity, its solubility in oxygen or other environmental gases or other gases, its ultraviolet, visible, and/or infrared absorption spectra, its absorption cross-section for electron and/or ion beams, its volatility, its ability to diffuse in the subsequently formed film, its purity from the standpoint of the presence of different solvent isomers, its purity from the standpoint of the presence of metal ions, its thermal stability, its ability to affect defects or nucleation points in the subsequently formed film, and environmental considerations regarding the solvent. Exemplary solvents include alkanes such as hexane, ketones such as methyl isobutyl ketone ("MIBK") and methyl ethyl ketone ("MEK") and propylene glycol monomethyl ether acetate ("PGMEA").

The concentration of the precursor in the solution may vary over a wide range and may be selected by one of ordinary skill in the art, up to and including its thickness and/or its sensitivity to illumination by light or particle beams, with minimal experimentation, to tailor the properties of the precursor film to the desired application.

However, the choice of the matrix has a very important influence on the properties of the desired film, which is not easily predictable by the person skilled in the art. For example, two precursors ML and ML ', each containing a metal M and one of two different ligands L or L', may be considered to form a film of the same desired material because, for example, mutually different portions of the ligands are removed into the hard mask during the conversion of the precursors. In fact, the same film products envisioned for these two similar reactants differ greatly in their properties. Examples of properties that may be affected in this process include the dielectric constant and the presence or absence of any secondary or tertiary structure in the film. The reason for this difference is likely to be related to the rate of formation of amorphous material and the ability of the photo-emissive ligand to remove energy from the photochemically-produced thinfilm of the desired material. The presence of ligand fragments during exposure can also affect the film formation process, affecting phenomena such as diffusion properties, nucleation, and crystal growth of the film.

In addition, the choice of precursors in film formation and photochemical exposure may substantially affect the reactivity of the desired material film, for example, by the gas composition of the atmosphere in which the desired film is formed. This can affect, for example, the oxidation rate of the deposited film, where either high or low rates can be advantageous depending on the desired product. Furthermore, it has been recognized that the effect of the matrix on the film recovery (i.e., the ability to minimize film cracking and shrinkage or tightness) can be influenced considerably by the choice of matrix, and that one of ordinary skill in the art can achieve the same result in other ways.

Chemical additives may optionally be present in the parent or parent solution. Their presence is based on any one or several of the following reasons: controlling the photosensitivity of subsequently deposited precursors or films, helping to improve the ability to deposit uniform defect-free films on substrates, changing the viscosity of the solution, increasing the film formation rate, helping to prevent cracking of the film during subsequent deposited film exposure, changing other bulk properties of the solution, and changing the properties of the film of desired materials in an important way. The additives are selected according to these criteria and those used in selecting the appropriate solvent. Preferably, the precursor or precursor solution is substantially free of particulate contaminants, thereby enhancing its film-forming properties.

The nature of the substrate onto which the precursor is plated is not critical to the process, although it will affect the precursor film deposition process and the solvent used for deposition (if used). Substrates include, but are not limited to, simple salts (e.g., CaF)₂) Semiconductor surfaces (including silicon), compound semiconductors (including silicon germanium and group III-V and II-VI semiconductors), printed and/or laminated circuit board substrates, metals, ceramics and glass. Silicon wafers, ceramic substrates and printed circuit boards have been widely used.Before its use in the present invention, the substrate has been coated with one or more layers, such as dielectric layers, photoresists, polyimides, metal oxides, thermal oxides, conductive materials, insulating materials, ferroelectric materials, or other materials used in the construction of electronic devices. In the case of printing with oxygen plasma, the precursor material may be used as a TSI agent, and the underlying layers are likely to be organic in nature, including but not limited to novolac resins, poly (methyl methacrylate) ("PMMA"), poly (methylglutamide) ("PMGI"), polyimide, and poly (p-hydroxystyrene) ("PHOST").

The preferred example, Compound SiR, was formed using the synthesis of Pike et al₂(O₂CCH₃)₂Wherein R is independently selected from acac, tbuacac (tributylacac). The acetylacetonate derivative silicon (IV) bis (acetylacetonate) diacetate has been shown to have the following structure in the solid state. While in solution, the trans-isomerization of the complex to the cis-form occurs until an equilibrium is reached between the two. The cis to trans ratio is about 1.6: 1.0. This isomerization reflects the higher dipole moment expected in cis.

Any silicon-containing photolytic, solvent-soluble complex may be used in the present invention. Particularly preferred parent types have the formula:

wherein M is a metal, e.g. Ti, V, Cr, Au, Mn, Fe, Co, Ni, Cu, Zn, Si, SnLi, Na, K, Ba, Sr, Mo, Ru, Pd, Pt, Re, Ir, Os, Zr, Ta, Ba, Sr, or Ha, with Si, Ti, Zr, Ta, Ba, Sr, or Ha being preferred, and Si being particularly preferred among the dielectric metals Si, Ti, Zr; r₁Independently H, OH, containGroups having one to fourteen carbon atoms, such as alkyl, substituted alkyl, alkenyl, aryl, heteroaryl, cycloalkyl and heterocycle, preferably alkyl, such as methyl, ethyl, n-propyl and/or isopropyl or butyl, with methyl and tert-butyl being particularly preferred or preferably aromatic; r₂H, OH independently, radicals containing one to fourteen carbon atoms, such as alkyl, substituted alkyl, aryl, heteroaryl, cycloalkyl and heterocycle, preferably alkyl, such as methyl, ethyl, n-propyl and/or isopropyl or butyl, where methyl and tert-butyl are particularly preferred, or preferably aromatic, preferably acetate or carboxylate, where n is a number from 1 to 4, preferably 2, and p is a number from 0 to 4.

Other photosensitive precursors may also be used, for example Si (Et)₂NCH₂CH₂O)₂(N₃)₂And (3) a complex. In certain embodiments, it is preferred to have multiple parent compounds in a layer. In selected cases, this contributes to the amorphous nature of the resulting film. More flexible conversion films can also be made that prevent cracking of the film during the solvent removal drying process and the precursor conversion process.

In the next step, a layer of precursor material is formed on the substrate. The amorphous complex-containing precursor is deposited on the substrate using methods well known in the art, such as spin coating or dip coating. The range of deposition methods and substrate choices for the precursor film is very light emitting, although the optimal substrate and deposition method will vary from precursor to precursor.

The thin film may be deposited on the substrate surface by spin coating. In this process, the substrate is typically rotated by placing it on a spinning die. The precursor solvent is dispensed onto the substrate while the substrate is spinning or prior to spinning, in a suitable solvent system. The precursor is deposited as a uniform thin film by this method. The thickness of the film was controlled by varying the rotation speed of the precursor solution and the substrate. In this spin coating process, it is advantageous to chemically modify the substrate surface in this way before coating in order to optimize the spin coating process. Spin coating has the advantage that it is a low cost method of depositing thin films.

In one embodiment, the thin film is deposited on the surface by spin coating molecules in a solvent. In this procedure, the precursor is dissolved in a solvent to form a precursor solution. The substrate surface is then placed on a surface that can be rotated. The substrate is fixed with a vacuum chuck (e.g., a commercial spin coater (e.g., from Headway or Laurell Corporation.) the precursor solution is dispensed onto the substrate surface before the start of rotation or as the substrate is rotated.

In one embodiment, the amorphous film of the complex is deposited on a silicon substrate by spin-coating. Reacting the complex Si (acac)₂(O₂CCH₃)₂Dissolved in chloroform. The solution was spin coated on Si (100). A drop of the solution was dispensed onto a silicon wafer spinning at 3000 rpm. The solvent evaporates, leaving an amorphous film of the complex on the substrate. The optical quality film left on the surface was found to be 273nm thick by optical interferometry. The presence of a thin film on a surface was determined using Fourier Transform Infrared (FTIR) and ultraviolet-visible light (UV-Vis) spectroscopy.

The film may also be formed by other methods known to those of ordinary skill in the art, including, but not limited to, spraying, dipping, evaporation, and various inking methods.

Typically, the precursor is dissolved in a solvent and then applied to a substrate. Suitable solvents include acetone, dimethyl sulfoxide, dimethylacetamide, 2-methoxyethanol, chloroform and the like. Any solvent that can dissolve the desired amount of the precursor and evaporate it using less energy than is required to convert the precursor can be used. Typically the solvent is polar. It is of course also possible to use mixtures of solvents in the process of the invention. The amount of solvent and the coating protocol (i.e., spin parameters) are selected so that a wide range of precursor thicknesses are deposited. Additives (which may also optionally act as solvents but are generally less volatile) may be added to improve the quality of the resulting film, for example, by preventing cracking or enhancing other film properties. Examples of such additives include, but are not limited to, alkanolamines, such as monoethanolamine and diethanolamine. One of ordinary skill in the art can determine other suitable additives to suit a particular application.

In one embodiment, the solvent is substantially removed by evaporation. Evaporation may be assisted by vacuum, heat, or a combination thereof.

The precursor film is then exposed to an amount of energy sufficient to convert at least a portion of the precursor. Conversion means ligand passage, e.g. loss of CO₂Becomes a different compound. Such different compounds have different, reduced solubility in solvents. In a preferred embodiment, the precursor is converted in a pattern.

It has been found that for aparticular energy input, a considerable amount of time is required to transform the precursor. For example, in the above examples, complete conversion was obtained by exposure to light for 10 to 35 minutes. This makes it difficult to perform a patterning process. Higher energies, such as using a more tightly focused energy beam, is one way to reduce exposure time. Alternatively, the precursor is exposed to a specific level of energy across the film and exposed to additional energy in a pattern. Typically, there must be a substantial degree (i.e., greater than 50%) of conversion, for example, to form a conversion layer that is not washed away by the solvent. For some precursors, it was found that heating the precursor to 400 ℃ for several hours prior to photolysis can reduce the required exposure time to below a few minutes. In this case, the thermal energy contributes to the conversion. However, in many embodiments, it is desirable to limit the heat treatment to less than 300 ℃ (e.g., about 150 ℃ to about 300 ℃) both before and after conversion. The combined form of energy may include diffused light/patterned light, diffused heat/electron beam, diffused heat/ion beam, diffused light/electron beam, diffused light/ion beam, and the like.

Light does not have to pass through a mask. For example, flood lighting (diffuse light) may be used if it is not necessary to pattern the material. Alternatively, if patterning is desired, a directional writing method may be used. In a common embodiment of the directional writing method, the laser beam is directed onto the surface in a continuous manner, and the exposure takes place only in the areas irradiated by the beam. Alternatively, the near field optical system may perform selective exposure of certain areas on the surface.

The desired conversion energy may be in the form of thermal energy, electromagnetic energy, a charged particle beam (i.e., an electron or ion beam), or a combination thereof. Inone embodiment, the film is exposed to electromagnetic radiation or electron or ion beams. The exposure causes the exposed areas to convert from the precursor material to a desired amorphous film of metallic (i.e., silicon-containing, in one embodiment) material.

The film is then exposed to a radiation source. Typically, the film is exposed to light directed through a photomask used to delineate a pattern on the surface. The mask includes a light transmitting region and a light absorbing region. The mask may also include an optical enhancement feature, such as phase shifting techniques.

In one embodiment, the amorphous film thus formed is then exposed to an energy source to initiate a chemical reaction that produces a useful substance. In this typical case, the exposure may be to electromagnetic radiation in the visible, ultraviolet, or X-ray regions. Such exposure may be performed in an oriented fashion such that the reaction occurs only in the exposed areas of the film.

This light-induced exposure of the film causes a chemical reaction within the film that changes the film from the precursor to the product. Applicants have found that a focused energy source can form a Si/SiOH structure that is 2 microns or less in at least one dimension.

Exposure may also be performed using an ion or electron beam. These are usually irradiated in a series of writing processes. Ions or electron beams are irradiated onto the precursor film to react at the exposed regions to produce a product film. The nature of the ion and electron beam exposure systems is such that these are typically done in vacuum. The deposition resulting from this process may be (depending on the conditions) a metal that is oxidized to form an oxide when exposed to air.

The properties of the thin film formed in this way may be amorphous, crystalline or liquid crystalline. The properties of the material depend on the conditions used to coat the material and the identity of the parent molecule. Particularly preferred for most semiconductor processes are those that are amorphous. An important result is that these films have sufficient molecular motion and disorder so that photodecomposition can be relatively efficient and high definition lithography can be performed.

Typically, the atmosphere used for exposure is air. For a variety of reasons, it is preferred to change the composition of the atmosphere during exposure. One reason for using short wavelength light is to increase the transmission of the illuminating light, since it is attenuated by air. It is also necessary to change the composition of the atmosphere to change the composition or properties of the product film. For example, exposure of the deposited metal in many cases in air or oxygen-containing atmospheres can result in the formation of metal oxides. By varying the humidity of the atmosphere, the amount of water in the film is varied. Water vapor is an important part of forming dielectric films, structures, or combinations thereof. In certain embodiments, a nitrogen atmosphere is advantageous.

In the simplest embodiment, exposure results in a chemical reaction to form a product that is insoluble in the solvent in which the precursor is dissolved. In this case, exposure of the surface to an appropriate solvent may leave a pattern of photochemical reaction products of the reaction of the precursor material.

Thermal energy may also be used to convert the precursor film. It has particular utility if certain areas are patterned to form a layer of fused silica, and then the remaining material is converted to silica oxide or hydroxide by pyrolysis in air and/or water vapor in a thermal reaction.

After conversion, unconverted precursors can be removed, for example, by washing with a solvent. The resulting converted silicon-containing film typically contains oxygen, carbon, and hydrogen. The carbon content may be as high as 60%, but is preferably less than about 40%.

The silicon-containing film is heat treated at, for example, about 100c to about 400 c, preferably about 150 c to about 350 c, and more preferably about 180 c to about 250 c, for a sufficient time, such as about 3 minutes to 6 hours, which results in a carbon-free silica-containing film composition. The use of water vapor, oxygen, nitrogen, and other atmospheres during the heat treatment process can provide films with different preselected properties. Advantageously, the heat treatment temperature is maintained at a minimum under certain process constraints (e.g., time) so as not to encourage migration of atoms (particularly metals) through existing layers and/or newly deposited layers.

In another, less preferred, method, a silicon-containing precursor that is not itself readily degraded by actinic energy may be used. In this example, it is desirable to use a free radical generator to catalyze photodegradation. There is no limitation on the compound capable of generating a radical upon irradiation with actinic radiation and the compound capable of generating an acid upon irradiation with actinic radiation, as long as they are capable of generating a radical or an acid. These compounds can be mixed with polymerizable silicon materials as a matrix for the thin film. The polymerization of the polymerizable precursor then forms a silicon-containing polymeric film upon exposure to energy (e.g., light or electron beam). Polysiloxanes, such as those described in U.S. patent 5,962,581 (incorporated herein by reference), may be used in this embodiment. The film may be converted to a silica dielectric layer by a subsequent thermal treatment. This method is less preferred because the content of organic matter that must be removed by heat treatment is rather high. Higher temperatures are also required for organic removal.

Advantageously, in any of the embodiments described herein, any free radical former may be added to the parent material.

Doped dielectric films containing from 0.1% to about 50% of the second metal oxide and optionally containing from about 0.1% to less than 50% of the third, fourth, fifth, etc. metal or metal oxide can also be formed. This enables one of ordinary skill in the art to make dielectric films specifically tailored for particular uses, e.g., to have particular chemical and/or dielectric properties, to improve adhesion with other layers, to have catalytically active surfaces, and the like.

Similarly, of course, semiconductor films and conductive films, especially embossed films, can be made using the present invention. All that is required is for the precursor material to contain multiple metals, where typically, but not necessarily, a single precursor molecule contains only one of the multiple metals used to form the alloy or doped dielectric film.

To form a multi-component film, a precursor material containing a single metal (i.e., silicon, hafnium, aluminum, etc.) is incorporated into the precursor solution in the desired amount. It is known that various metals require different ligands to have the solubility and photoreactivity required to effectively form a substrate. It has been determined that if different complexes have different activation energies, delamination can occur within the film if the source of the conversion energy is adjusted to take advantage of the difference. Similarly, lateral variations are likely to occur in the same manner. The precursor is then coated on a substrate, converted (or partially converted), developed by removing the unconverted portions, and heat treated as desired.

Advantageously, a positive film is formed from the converted material. Less preferred are negative films, i.e., films that are cleaned of the converted portion, because the alkaline solvent required to remove the silica introduces metal ions in the substrate and because unwanted silica precipitates from the alkali.

Example 1

An amorphous film of the complex is deposited on a silicon substrate by spin-coating. Reacting the complex Si (acac)₂(O₂CCH₃)₂Dissolved in chloroform. The solution was spin coated on Si. Dividing one drop of the solution intoMounted on a silicon wafer rotating at 3000 rpm. The solvent evaporates, leaving an amorphous film of the complex on the substrate. The optical quality film left on the surface was found to be 273nm thick by optical interferometry. The presence of a thin film on a surface was determined using Fourier Transform Infrared (FTIR) and ultraviolet-visible light (UV-Vis) spectroscopy.

The FTIR spectrum of the film was recorded. The sample was then exposed to 254nm light for 1 minute. The second spectrum was recorded. This process was repeated several times until no vibrational bands caused by the ligand were observed. Fig. 1 shows the spectral change of FTIR in photolysis experiments. Clearly, the vibrational band induced by the ligand reduces intensity due to photolysis. Proportional decay of the carboxylate and acetylacetonate bands was observed. Likewise, no evidence of the formation of thermally stable intermediates was found. The figure shows the disappearance from the film by photolysis of the ligand.

One strip was observed at 1100cm^-1The surrounding broad band indicates the formation of Si-O-Si bonds in the film. This corresponds to the expected SiO₂At about 1085cm^-1The surrounding absorption band.

The surface formed in this way was analyzed by auger electron spectroscopy and found to contain Si (22%), O (50%) and C (28%). The sample was heat-treated at 200 ℃ for 3 hours to give a composition of SiO₂A carbon-free film of (1).

Example 2

Deposition of parent Cu on substrate₂(μ-Et₂NCH₂CH₂O)₂(N₃)₂. The Cu was then treated with ultraviolet light (254nm) in a nitrogen atmosphere₂(μ-Et₂NCH₂CH₂O)₂(N₃)₂The film is photolyzed. The progress of the reaction was monitored by means of Fourier transform infrared spectroscopy. After complete photolysis, the conductivity of the film was measured. The film was found to have a conductivity of 1.8. mu. omega. cm. The film was analyzed and found to contain copper.

Alternatively, similar precursor films exposed to air produce copper oxide. The oxide film may be reduced at elevated temperatures by hydrogen or any other suitable reducing agent to produce a copper film.

Example 3

Will contain Cu₂(μ-Et₂NCH₂CH₂O)₂(N₃)₂And Cu₂(μ-Et₂NCH₂CH₂O)₂(NCO)₂A mixture of the two precursors is deposited to form a thin film. Photolyzing the film to form a conductive copper-based film。

In another embodiment, Cu is added₂(μ-Et₂NCH₂CH₂O)₂(N₃)₂Thin film deposition, photolysis through a lithographic mask. The resulting film was rinsed with ethyl acetate, leaving oxidation on the surfaceA copper pattern.

Example 4

The procedure of example 1 was followed to investigate tributylacetylacetonate complex Si (O)₂C₂H₃)₂(O₂C₁₁H₁₉)₂. An amorphous film is deposited on a silicon substrate. The film was photolyzed for several periods of time. FIG. 2 summarizes the spectral change of the photolysis experiment. The graph shows the photolysis with a carboxylic acid ester (1700 cm)^-1) Monotonic decay in absorption band intensity associated with tributyl acetylacetonate ligand (1549, 1516 cm). The alkyl FTIR bands also decay at a rate comparable to the carboxylate and acetylacetonate bands. This result indicates separation from the film by photolysis of the ligand. This will result in a good quality film with excellent surface smoothness and without the cracking associated with volume shrinkage.

Advantageously, in many embodiments, the substrate does not require pretreatment with, for example, adhesives and flatting agents.

Advantageously, the use of a precursor containing a single Si atom readily forms an amorphous film upon development. This is in contrast to, for example, crosslinked polysiloxanes which form more crystalline structures.

No evidence of a thermally stable intermediate was detected. Also, in a similar manner to the acetylacetonate of example 1, at 1241 to 1000cm^-1In the range of (1) in which the peak is 1039cm, the generation of a broad vibration band is seen^-1. The ribbon is associated with the deformation vibration of the Si-O-Si bonds of the silica network.

The surface formed in this way was analyzed by auger electron spectroscopy and found to contain Si (20%), O (48%) and C (32%). The sample was heat-treated at 200 ℃ for 3 hours to give a composition of SiO₂A carbon-free film of (1).

Example 5

The silicon dioxide structure was patternedon a silicon substrate using the precursors of examples 1 and 3. Both silicon compounds successfully completed the deposition process. In one experiment, the acetylacetonate (acac) complex Si (acac)₂(O₂CCH₃)₂The chloroform solution of (a) was spin-coated on a silicon wafer with a spin speed of 3000 rpm. A photolithographic mask is then sandwiched over the pellicle. The mask/film device was then exposed to 254 ultraviolet light. After 3 hours of photolysis, the mask was removed and the wafer was rinsed with chloroform. All unexposed areas were dissolved in chloroform leaving a pattern on the silicon surface as shown in fig. 3.

The resolution obtained is satisfactory and lines of 2 x 50 microns can be easily produced. These experiments demonstrate the ability of silicon dioxide to form patterns on silicon wafers by photochemical reactions using silicon acetylacetonate complexes.

Example 6

In another embodiment, Cu is fabricated as a thin film₂(μ-Et₂NCH₂CH₂O)₂(N₃)₂And UO₂(O₂CC₅H₁₁)₂. The material is photolyzed to produce a thin film of the complex copper-uranium oxide.

It will be appreciated by those skilled in the art that variations may be made to the above-described method without departing from the scope of the invention.

Claims (38)

1. A method of making an embossed dielectric film on a substrate, comprising:

depositing a precursor film comprising a solvent and a metal precursor complex of the formula,

wherein n is an integer of 1 to 4, R₁Independently selected from H, OH or a group containing 1 to 14 carbon atoms, p is an integer from 0 to 4, R₂Independently selected from H, OH, containing 1 to 14 carbon atomsA group, a group containing 1 to 8 nitrogen atoms, or a halogen, M is a metal selected from Si, Ti, Zr, Ta, Ba, Sr, Hf, or mixtures thereof;

exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, in an amount sufficient to cause the ligand to disassociate from the molecules of the precursor complex, such that the exposed portion of the precursor film is insoluble in the solvent and carbon is lost due to exposure of the film;

removing the unexposed mother film; and are

The film is heated to a temperature of from about 150 c to about 350 c for a time sufficient to remove substantially all of the carbon from the film, thereby forming an amorphous dielectric film comprising a metal oxide, metal hydroxide, or mixture thereof.

2.The method of claim 1, further comprising the steps of: at least half of the solvent is removed from the film prior to exposing the film to an amount of electromagnetic radiation, heat, ion beam, electron beam, or a combination thereof sufficient to remove a sufficient number of n ligands.

3. The method of claim 1, wherein M is Si, n is 2, and p is 1 or 2, wherein the atmosphere over the film contains oxygen.

4. The method of claim 1, wherein M is Si, n is 2, p is 1 or 2, and the atmosphere over the film contains water vapor when the film is heated to about 150 ℃ to about 300 ℃ for a time sufficientto remove substantially all of the carbon from the film.

5. The method of claim 1 wherein the precursor film comprises a plurality of metal precursors, such that a plurality of metal oxides/hydroxides are present in the dielectric film.

6. The method of claim 1, wherein R₁Is selected from CH₃And C (CH)₃)₃。

7. The method of claim 1, wherein exposing comprises exposing to electromagnetic energy through a mask, thereby forming a dielectric pattern.

8. The method of claim 1, wherein exposing comprises exposing the precursor film to a directed beam of electromagnetic radiation, heat, an ion beam, an electron beam, wherein the beam has a size of about 10 μ or less, thereby forming the dielectric pattern.

9. The method of claim 1, wherein the film is heated to between about 150 ℃ and about 250 ℃ for a time of about 10 minutes to about 10 hours.

10. The method of claim 1, wherein R₂Including- (OOC) -R₃Wherein R is₃Is C₁To C₉Alkyl, aryl or heterocyclic.

11. The method of claim 1 wherein M is Ti, Zr, Ta, Hf, or a mixture thereof, wherein the dielectric film is an amorphous high-k dielectric film having a dielectric constant of at least 5, and wherein the precursor film further comprises Ca, Sr, Al, Sc, La, or a mixture thereof in a molar ratio to M of about 0.1 to about 0.6.

12. A method of making an embossed dielectric film on a substrate, comprising:

depositing on a substrate a composition comprising a solvent and a compound of formula M_fL_gX_hWherein M is selected from Si, Ti, Zr, Ta, Ba, Sr, Hf or mixtures thereof, and L is a metal precursor complex of the formula (R)₂NCR₂′CO-)、(-NRCR₂'CO-), R- (CO) ═ CH-CR' O-, - (OCR) -CH-CR 'O-, or mixtures thereof, wherein each R and R' is independently selected from F, Cl, Br, I, H, OH, C_nH_m、OC_nH_m、O₂C_nH_m、OC_nH_mA_xB_y、O₂CnH_mA_xB_yAnd C_nH_mA_xB_yWherein X is independently selected from C_nH_m、OC_nH_m、O₂C_nH_m、OC_nH_mA_xB_y、O₂C_nH_mA_xB_y、C_nH_mA_xB_y、N₃、NCO、NO₃、NO₂Anions of Cl, Br, I, F, CN, OH and H, wherein A and B are independently selected from N, O, S and halogen, and F, F, H, and H,g. h, n, m, x and y represent integers;

exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, such that the exposed portion of the precursor film is insoluble in the solvent, and wherein carbon is lost as a result of exposing the film;

removing the unexposed precursor film from the substrate; and

the film is heated at a temperature and for a time sufficient to remove substantially all of the carbon from the film, thereby forming an amorphous dielectric film comprising ametal oxide, a metal hydroxide, or a mixture thereof.

13. The method of claim 12, wherein M is Si, f is 1, L is 1 or 2, and B is 1 to 3, wherein the atmosphere over the film during heating contains oxygen.

14. The method of claim 12, wherein M is Si and the atmosphere over the film contains water vapor when the film is heated to a temperature of about 150 ℃ to about 300 ℃ for a time sufficient to remove substantially all of the carbon from the film.

15. The method of claim 12 wherein the precursor film comprises a plurality of metal precursors such that there are a plurality of metal oxides/hydroxides in the dielectric film.

16. The method of claim 1, wherein R and R' are independently selected from H, CH₃And C (CH)₃)₃Wherein at least one X is O₂CCH₃。

17. A method of making an embossed dielectric film on a substrate, comprising:

depositing on a substrate a composition comprising a solvent and a compound of formula M_fL_gX_hWherein M is selected from the group consisting of Si, Ti, Zr, Ta, Ba, Sr, Hf, or mixtures thereof, at least one L is a ligand comprising mu-aminopropyl-2-alkoxide, diethylaminoethyl-2-alkoxide, diethylaminobutyl-2-alkoxide, acetylacetonate, alkyl acetylacetonate, or mixtures thereof, and X is independently selected from the group consisting of N₃、NCO、NO₃、NO₂Cl, Br, I, CN, OH, H and CH₃And O₂C-R, wherein R is C₁To C₁₄Alkyl, aryl or heterocycle, f, g and h represent integers;

removing at least a portion of the solvent from the precursor film;

exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, thereby converting the portion of the precursor film such that the exposed portion of the precursor film is insoluble in the solvent, wherein carbon is lost as a result of exposing the film;

removing the unexposed precursor film from the substrate; and

the film is heated at a temperature and for a time sufficient to remove substantially all of the carbon from the film, thereby forming an amorphous dielectric film comprising a metal oxide, a metal hydroxide, or a mixture thereof.

18. The method of claim 17, wherein the step of removing the solvent from the film comprises exposing the film to a temperature of about 80 ℃ to about 200 ℃, wherein the temperature does not cause substantial conversion of the precursor, followed by exposing the film to an amount of electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof sufficient to remove a sufficient number of n ligands.

19. The method of claim 17, wherein M is Si and the atmosphere over the film contains oxygen, water vapor, or a mixture thereof when the film is heated to remove substantially all of the carbon in the film.

20. The method of claim 17 wherein M is Ti, Zr, Ta, Hf, or mixtures thereof, wherein the dielectric film is an amorphous high-k dielectric film having a dielectric constant of at least 5, and wherein the precursor film further comprises Ca, Sr, Al, Sc, La, or mixtures thereof in a molar ratio to M moles of about 0.1 to about0.6.

21. A method of making an embossed dielectric film on a substrate, comprising:

at least one precursor material is selected from the group consisting of metal complexes comprising at least one ligand selected from the group consisting of substituted or unsubstituted acetylacetonates, acetonylacetones, dialkyl dithiocarbamates, carboxylic acids, carboxylic esters, pyridines, azidos, amines, diamines, arsines, phosphines, diphosphines, aromatic hydrocarbons, hydroxyl groups, alkoxy groups, alkyl groups, aryl groups, oxy groups, oxalyl groups, halides, hydrogen, hydrides, dihydrides, cyano groups, carbonyl groups, nitro groups, nitrites, nitrates, nitrosyl groups, ethylene, acetylene, thiocyano groups, isothiocyanato groups, hydrates, carbonates, amines, thiocarbonyl groups, carboxylic acid groups, and mixtures thereof, and at least one metal selected from the group consisting of Si, Ti, Zr, Ta, Ba, Sr, Hf, or mixtures thereof, wherein the metal complex is photodegradable.

Forming a layer containing the unconverted precursor on a substrate;

partially converting at least a portion of the unconverted mother liquor layer;

substantially removing at least a portion of the layer of unconverted precursor to form a pattern; and

converting at least a portion of the partially converted precursor layer to form a dielectric film, wherein the dielectric film is substantially amorphous with an average dielectric constant of at least about 2.

22. The method of claim 21, wherein the ligand is selected from the group consisting of acac, carboxylic acid groups, alkoxy groups, azido groups, carbonyl groups, nitrate groups, amines, halides, nitro groups, and mixtures thereof.

23. The method of claim 21, further comprising exposing the converted precursor layer to an oxygen-donating or OH-donating environment under temperature and pressure conditions such that the converted precursor layer forms a metal oxide, metal hydroxide, or a mixture thereof.

24. The method of claim 21 wherein the layer on the substrate containing the unconverted precursor further contains an alkanolamine.

25. A method of making an embossed dielectric film on a substrate, comprising:

depositing a layer containing a compound of formula M on a substrate_fL_gX_hA precursor film of the first metal precursor complex of (a), wherein:

m is selected from Si, Ti, Zr, Ta, Ba, Sr, Hf or mixtures thereof;

at least one L is of the formula-Y¹-Z¹R⁵ _a-Z¹R⁵ _a-Z¹R⁵Z_a-Y¹The photolytic ligand of (a), wherein at least one Y¹Selected from N or O and bonded to M, Z¹Independently is N or C, and R⁵The groups are independently selected from a) H, b) OH, c) O, d) a group containing one to about fourteen carbon atoms, e) a group containing one to about eight nitrogen atoms, and f) a halide, and "a" is an integer from 0 to 2, and

at least one X is independently selected from a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_m、O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, m, x and y represent integers and n is an integer from 0 to 14;

exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, such that the exposed portion of the precursor film is insoluble in the solvent, wherein carbon is lost as a result of exposing the film;

removing the unexposed precursor film from the substrate; and

the film is heated at a temperature and for a time sufficient to form an amorphous dielectric film comprising a metal oxide, a metal hydroxide, or a mixture thereof.

26. The method of claim 25 wherein M is selected from the group consisting of Ti, Zr, Ta, Ba, Sr, Hf or mixtures thereof, and wherein the precursor film comprises a compound of formula M ″_fL′_gX′_hWherein the molar ratio of M ' to M in the precursor film is from 0.01 to 0.9, M ' is selected from calcium, strontium, aluminum, lanthanum, scandium, or mixtures thereof, at least one L ' is a photolytic ligand, and at least one X is selected from a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_mOr O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, m, x and y represent integers which are the same as or different from the integers in the first metal precursor complex, and n is an integer from 0 to 14;

27. the method of claim 25, wherein the precursor film comprises a compound of the formula M'_fL′_gX′_hThe surface-active catalytic parent material of (a),

wherein M 'is selected from the group consisting of gold, platinum, palladium, ruthenium, rhodium, iridium, copper, silver, iron, or mixtures thereof, at least one L' is a photolytic ligand, and at least one X is selected from the group consisting of a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_mOr O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, m, x and y represent integers which are the same or different from those in the first metal precursor complex, and n is an integer from 0 to 14, and

the amount of M' "in the dielectric film is an amount that is insufficient to cause substantial leakage through the dielectric film but is capable of modifying the exposed surface of the dielectric film to provide a catalytic template for the formation of the next layer deposited thereon.

28. The method of claim 27, wherein the molar ratio of M' "to M is from about 0.01% to about 25%.

29. The method of claim 25, wherein X is independently selected from a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_mOr O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide.

30. A method of making an embossed dielectric film on a substrate, comprising:

depositing on a substrate a precursor film comprising:

has a chemical formula of M_fL_gX_hWherein M is selected from the group consisting of Si, Ti, Zr, Ta, Ba, Sr, Hf, or mixtures thereof; at least one L is a decomposable ligand that decomposes upon exposure to a first energy, and at least one X is independently selected from a) H, b) OH, C) O, d) substitutedor unsubstituted C_nH_m、OCC_nH_m、O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, m, x and y represent integers and n is an integer from 0 to 14;

a chemical formula of M_fL′_gX′_hWherein M 'is selected from calcium, strontium, aluminum, lanthanum, scandium, or mixtures thereof, at least one L' is a decomposable ligand that decomposes upon exposure to a second energy, and at least one X is selected from a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_m、O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, m, x and y represent a group bonded to the first goldThe integers in the parent complex are the same or different, and n is an integer from 0 to 14; and

a solvent;

exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, thereby providing energy sufficient to decompose L and L' at the exposed portion of the precursor film, converting the precursor material into an intermediate insoluble in a developing solvent, wherein carbon is lost as a result of exposing the film;

contacting the unexposed film with a developing solvent to remove the unexposed precursor film from the substrate; and

the film is heated at a temperature and for a time sufficient to form an amorphous dielectric film comprising an oxide, hydroxide, or mixture thereof of M and M 'such that the molar ratio of M' to M in the dielectric film is from 0.01 to 0.9.

31. The method of claim 30 wherein the first energy is different from the second energy to energize exposed portions of the precursor film in a manner that molar ratios of M "and M are unequal for different volumes in the dielectric film.

32. A method of making an embossed dielectric film on a substrate, comprising:

depositing on a substrate a precursor film comprising:

has a chemical formula of M_fL_gX_hWherein M is selected from the group consisting of Si, Ti, Zr, Ta, Ba, Sr, Hf, or mixtures thereof; at least one L is a decomposable ligand that decomposes upon exposure to a first energy, and at least one X is independently selected from a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_mOr O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, m, x and y represent integers and n is an integer from 0 to 14;

the chemical formula is M'_fL′_gX′_hSurface active metal precursor ofA bulk complex wherein M 'is selected from gold, platinum, palladium, ruthenium, rhodium, iridium, copper, silver, or mixtures thereof, at least one L' is a photolytic ligand that decomposes upon exposure to a second energy, and at least one X is selected from a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_mOr O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, m, x and y represent integers which are the same as or different from the integers in the first metal precursor complex, and n is an integer from 0 to 14;

exposing at least a portion of the precursor film to electromagnetic radiation, heat, an ion beam, an electron beam, or a combination thereof, thereby providing energy sufficient to decompose L and L' at the exposed portion of the precursor film and convert the precursor material into an intermediate insoluble in a developing solvent, wherein carbon is lost as a result of exposing the film;

contacting the unexposed film with a developing solvent to remove the unexposed precursor film from the substrate; and

the film is heated at a temperature and for a time sufficient to form an amorphous dielectric film comprising an oxide, hydroxide or mixture thereof of M and M ', such that the amount of M' in the dielectric film is an amount insufficient to cause substantial leakage through the dielectric film but to modify the exposed surface to provide a catalytic template for the formation of the next layer deposited thereon.

33. The method of claim 32 wherein the first energy is different from the second energy such that the molar ratio of M' "to M in the vicinity of and at the exposed surface of the dielectric film is greater than that of other portions of the dielectric film to energize the exposed portions of the precursor film.

34. The method of claim 32, wherein the precursor film further comprises a compound of formula M ″_fL′_gX′_hWherein M' is selected from the group consisting of calcium, strontium, and mixtures thereof,Aluminum, lanthanum, scandium, or mixtures thereof, at least one L' being exposed to a third energyAt least one X is selected from a) H, b) OH, C) O, d) substituted or unsubstituted C_nH_m、OCC_nH_m、O₂CC_nH_mAnd e) a group containing one to about eight nitrogen atoms and f) a halide, wherein f, g, h, n, M, x and y represent integers which are thesame or different from those in the first metal precursor complex, and n is an integer from 0 to 14, wherein the molar ratio of M' to M in at least a portion of the dielectric film is from 0.1 to 0.6.

35. The method of claim 34, wherein the first energy is different from the third energy such that the molar ratio of M "and M of one exposed portion is greater than that of a second exposed portion to provide energy to the exposed portion of the precursor film.

36. The method of claim 32, wherein L is-O-CR⁵ _a-CR⁵ _a-CR⁵ _a-O-wherein R⁵The groups are independently selected from a) H, b) OH, c) O, d) groups containing one to about fourteen carbon atoms, e) groups containing one to about eight nitrogen atoms, and f) halides.

37. The method of claim 32 wherein at least one of L and L' is an β -dione ligand of formula (R)₂NCR₂'CO) wherein R and R' are independently selected from H, OH, O, C_nH_m、OC_nH_m、OC_nH_mA_xB_y、C_nH_mA_xB_yAnd halogen, wherein A and B are independently selected from main group elements, and f, g, h, n, m, x and y represent integers.

38. The method of claim 32, wherein at least one of L and L' is a ligand comprising a substituted or unsubstituted aminoalkane-2-alkoxide, an acetylacetonate, an alkyl acetylacetonate, or a mixture thereof.