Organic anti-reflective coatings deposited by chemical vapor deposition (CVD)

Abstract

An improved method for applying organic anti-reflective coatings to substrate surfaces and the resulting precursor structures are provided. Broadly, the methods comprise chemical vapor depositing (CVD) a polymer on the substrate surface. In one embodiment, the polymer are formed of highly strained monomers (e.g., monomers having a strain energy of at least about 10 kcal/mol) which themselves comprise two cyclic moieties joined to one another via an alkyl chain. One preferred such monomer is 1,4-dixylylene. The CVD processes comprise heating the monomer so as to vaporize the monomer and then pyrolizing the monomer in the resulting vapor to form stable diradicals which are subsequently polymerized on a substrate surface in a deposition chamber. The inventive methods are useful for providing highly conformal anti-reflective coatings on large substrate surfaces having super submicron (0.25 μm or smaller) features.

Description

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention is broadly concerned with methods of forming anti-reflective coating (ARC) layers on silicon and dielectric materials as well as the resulting integrated circuit precursor structures. More particularly, the inventive methods comprise providing a quantity of a polymer comprising highly strained monomers and vaporizing that polymer. The resulting vapor is then pyrolized to form stable diradicals which are subsequently polymerized on the surface of a substrate. A photoresist layer is applied to the formed ARC layer, and the remaining microphotolithographic process steps carried out.

[0004] 2. Description of the Prior Art

[0005] Integrated circuit manufacturers are consistently seeking to maximize silicon wafer sizes and minimize device feature dimensions in order to improve yield, reduce unit case, and increase on-chip computing power. Device feature sizes on silicon chips are now submicron in size with the advent of advanced deep ultraviolet (DUV) microlithographic processes. However, reducing the substrate reflectivity to less than 1% during photoresist exposure is critical for maintaining dimension control of such submicron features. Therefore, light absorbing organic polymers known as anti-reflective coatings (ARC) are applied beneath photoresist layers in order to reduce the reflectivity normally encountered from the semiconductor substrates during the photoresist DUV exposure. These organic ARC layers are typically applied to the semiconductor substrates by a process called spincoating. While spincoated ARC layers offer excellent reflectivity control, their performance is limited by their non-uniformity, defectivity and conformality constrictions, and other inefficiencies inherent within the spincoating process. As the industry approaches adoption of eight-inch or even twelve-inch semiconductor substrates, the inherent inefficiencies of the spincoating process become magnified.

[0006] When spincoated at thicknesses ranging from 500 Å to 2500 Å, commercial organic ARC layers require polymers specifically designed to prevent molecular intermixing with adjacent photoresist layers coated and baked thereon. Although high optical density at DUV wavelengths enable these pre-designed polymers to provide effective reflectivity control at prior art dimensions, they have numerous drawbacks.

[0007] For example, spincoated ARC layers tend to planarize or unevenly coat surface topography rather than form highly conformal layers (i.e., layers which evenly coat each aspect of the substrate and the features). For example, if an ARC with a nominal layer thickness of 1000 Å is spincoated over raised features having feature heights of 0.25 microns, the layer may prove to be only 350 Å thick on top of the features, while being as thick as 1800 Å in the troughs located between the raised features.

[0008] When planarization occurs with these ultra microscopic feature sizes, the ARC layer is too thin on the top of the features to provide the desired reflection control at the features. At the same time, the layer is too thick in the troughs to permit efficient layer removal during subsequent plasma etch. That is, in the process of clearing the ARC deposit from the troughs by plasma etch, the sidewalls of the resist features become eroded, producing microscopically-sized, but significant, changes in the feature shape and/or dimensions. Furthermore, resist thickness and edge acuity may be lost, which can lead to inconsistent images or feature patterns as the resist pattern is transferred into the substrate during subsequent etching procedures.

[0009] Other problems can occur as well due to the fact that spincoating of these ultra thin ARC layers takes place at very high speeds in a dynamic environment. Accordingly, pinholes, voids, bubbles, localized poor adhesion, center-to-edge thickness variations, and other defects occur as a consequence of attendant rapid or non-uniform solvent evaporation, dynamic surface tension, and liquid-wavefront interaction with surface topography. The defects stemming therefrom become unacceptable with increased wafer size (8″-12″) and when patterning super submicron (0.25 μm or smaller) features.

SUMMARY OF THE INVENTION

[0010] The present invention overcomes these problems by broadly providing improved methods of applying anti-reflective coatings to silicon and dielectric materials or other substrates (e.g., Al, W, WSi, GaAs, SiGe, Ta, TaN, and other reflective surfaces) utilized in circuit manufacturing processes.

[0011] In more detail, the inventive methods comprise depositing an anti-reflective compound in a layer on the substrate surface by chemical vapor deposition (CVD) processes. A layer of photoresist is applied to the anti-reflective layer to form a precursor structure which can then be subjected to the remaining steps of the circuit manufacturing process (i.e., applying a mask to the photoresist layer, exposing the photoresist layer to radiation at the desired wavelength, developing and etching the photoresist layer).

[0012] In one embodiment the anti-reflective compound comprises a polymer which preferably includes a monomer comprising two cyclic moieties joined via a linkage group bonded to a first location (either directly to a member of the cyclic ring, or to a functional group bonded to the cyclic ring) on one of the cyclic moieties and further bonded to a first location on the other of the cyclic moieties. Preferably, the two cyclic moieties are joined by more than one such linkage group, and even more preferably the two selected moieties are joined by two such linkage groups, with each additional linkage group being bonded to second, third, etc. locations on the respective cyclic moieties.

[0013] Preferably the linkage group is an alkyl chain such as an ethyl, propyl, or butyl group. The monomer should be highly strained so that it is easily cleaved into stable diradicals by exposure of the monomer to energy (e.g., heat, UV light). Thus, the strain energy of the monomer should be at least about 10 kcal/mol, preferably at least about 20 kcal/mol, and more preferably from about 30-50 kcal/mol.

[0014] It is preferred that at least one of the cyclic moieties be aromatic, with preferred aromatic moieties being those selected from the group consisting of benzene, naphthalene, anthracene, thiophene, furan, and pyrrole moieties. Formula I schematically depicts a particularly preferred monomer structure. 1

[0015] In a preferred Formula I, the aromatic rings are each benzene and n=2, thus forming 1,4-dixylylene. Other preferred monomer structures include parylene-D and parylene-C.

[0016] In an alternate embodiment, the anti-reflective compound comprises a polymer which includes a monomer comprising 1,4-dixylylene having two to four halogen atoms (e.g., chlorine) bonded thereto, or xylenes having at least one functional group bonded thereto, wherein the functional group is readily cleaved during the CVD process. Formula II schematically depicts the monomer of this embodiment. 2

[0017] where each X is individually selected from the group consisting of: 3

[0018] where each R is individually selected from the group consisting of hydrogen and alkyl groups (preferably C1-C4 branched and unbranched) and the “*” designates the atom which is bonded to the CH2 group which, in turn, is bonded to the benzene ring as depicted in Formula II.

[0019] The chemical vapor deposition process to which the anti-reflective compound is subjected comprises subjecting the compound to sufficient temperatures and pressures so as to cause the solid compound to sublime to form a vapor. This is preferably accomplished by heating the compound to a temperature of from about 35-160° C., and more preferably from about 85-125° C., at a base pressure of from about 2-50 mTorr, and more preferably from about 10-30 mTorr, over the course of the entire process. Even more preferably, this heating is accomplished by running a temperature gradient wherein the temperature is raised about 1 ° C. about every 5-7 minutes for about 2½ hours followed by an increase of about 1-2° C. over a time period of about 10 minutes after which the final temperature is maintained for about 4-6 minutes.

[0020] The resulting vapor is then subjected to a process whereby the monomers in the vapor are cleaved. Preferably, this monomer cleavage is effected by pyrolizing the monomer by heating it to a temperature of from about 580-700° C., and more preferably from about 630-670° C. The monomers should be cleaved at the bond between two carbon atoms on each linkage group so as to yield stable diradicals.

[0021] Finally, the cleaved monomers or diradicals are caused to polymerize on the surface of the substrate. This is preferably accomplished by introducing the cleaved monomers into an ambient-temperature, deposition chamber in the presence of the desired substrate where the cleaved monomers are simultaneously adsorbed and polymerized on the substrate surface. This step is preferably accomplished at a temperature of from about 20-25° C., with the spin speed of the rotating shelf on which the substrate is situated preferably being revolved from about 2-10 rpm, and more preferably from about 2-5 rpm.

[0022] The equipment utilized to carry out the foregoing CVD process can be any conventional CVD equipment so long as the above-described temperatures can be attained by the equipment. The primary modification required for conventional CVD equipment is that the deposition chamber must be modified to accommodate the particular size of the substrate (e.g., an 8-inch silicon wafer), and it must include a mechanism for rotating the substrate (such as a rotating shelf) at a speed of about 2 rpm.

[0023] The resulting precursor structure has an anti-reflective coating layer which is surprisingly defect-free. Thus, there are less than 0.1 defects/cm2 of anti-reflective layer (i.e., less than about 15 defects per 8-inch wafer), and preferably less than 0.05 defects/cm2 (i.e., less than about 7.5 defects per 8-inch wafer), when observed under an optical microscope. Furthermore, these essentially defect-free films can be achieved on 6-12 inch substrates having super submicron features (i.e., less than about 0.25 μm in height). As used herein, “defects” is intended to include pinholes, dewetting problems where the film doesn't coat the surface, and so-called “comets” in the coating (i.e., a foreign particle contacts the substrate surface causing the coating to flow around the particle).

[0024] The anti-reflective layers prepared according to the invention can be formulated to have a thickness of from about 300-5000 Å, and can be tailored to absorb light at the wavelength of interest, including light at a wavelength from about 150-500 nm (e.g., 365 nm or I-line wavelengths, and 435 nm or g-line wavelengths), and preferably from about 190-300 nm. Thus, the anti-reflective layers will absorb at least about 90%, and preferably at least about 95%, of light at wavelengths of from about 150-500 nm. Furthermore, the anti-reflective layers have a k value (i.e., the imaginary component of the complex index of refraction) of at least about 0.1, preferably at least about 0.35, and more preferably at least about 0.4 at the wavelength of interest.

[0025] The deposited anti-reflective layer is also substantially insoluble in solvents utilized in the photoresist which is subsequently applied to the anti-reflective layer. That is, the thickness of the layer will change by less than about 10%, and preferably less than about 5% after contact with the photoresist solvent. As used herein, the percent change is defined as: 1$100·\frac{\begin{array}{c}\&LeftBracketingBar;\left(\mathrm{thickness}\mathrm{prior}\mathrm{to}\mathrm{solvent}\mathrm{contact}\right)-\\ \left(\mathrm{thickness}\mathrm{after}\mathrm{solvent}\mathrm{contact}\right)\&RightBracketingBar;\end{array}}{\left(\mathrm{thickness}\mathrm{prior}\mathrm{to}\mathrm{solvent}\mathrm{contact}\right)}$

[0026] The anti-reflective layers deposited on substrate surfaces according to the invention are also highly conformal, even on topographic surfaces (i.e., surfaces having raised features of 1000 Å or greater and/or having contact or via holes formed therein and having hole depths of from about 1000-15,000 Å). Thus, the deposited layers have a percent conformality of at least about 85%, preferably at least about 95%, and more preferably about 100%, wherein the percent conformality is defined as: 2$100·\frac{\begin{array}{c}\&LeftBracketingBar;\left(\mathrm{thickness}\mathrm{of}\mathrm{the}\mathrm{film}\mathrm{at}\mathrm{location}A\right)-\\ \left(\mathrm{thickness}\mathrm{of}\mathrm{the}\mathrm{film}\mathrm{at}\mathrm{location}B\right)\&RightBracketingBar;\end{array}}{\left(\mathrm{thickness}\mathrm{of}\mathrm{the}\mathrm{film}\mathrm{at}\mathrm{location}A\right)},$

[0027] wherein: “A” is the centerpoint of the top surface of a target feature when the target feature is a raised feature, or the centerpoint of the bottom surface of the target feature when the target feature is a contact or via hole; and “B” is the halfway point between the edge of the target feature and the edge of the feature nearest the target feature. When used with the definition of percent conformality, “feature” and “target feature” is intended to refer to raised features as well as contact or via holes. As also used in this definition, the “edge” of the target feature is intended to refer to the base of the sidewall forming the target feature when the target feature is a raised feature, or the upper edge of a contact or via hole when the target feature is a recessed feature.

[0028] Finally, in addition to the aforementioned anti-reflective layer properties, the instant invention has a further distinct advantage over prior art spin-coating methods which utilize large quantities of solvents. That is, the instant methods avoid spin-coating solvents which often require special handling. Thus, solvent waste is minimized and so are the negative effects that solvent waste can have on the environment. Furthermore, overall waste is minimized with the inventive process wherein substantially all of the reactants are consumed in the process.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG. 1 is a graph demonstrating a simulated substrate reflectivity (polysilicon) vs. ARC thickness at a wavelength of 193 nm for a sample prepared according to the invention;

[0030] FIG. 2 is an SEM photograph (70,000×) showing a 600 Å thick film on a 1000 Å topography applied according to the inventive methods;

[0031] FIG. 3 is an SEM photograph (60,000×) showing a 600 Å thick film on a 2000 Å topography applied according to the inventive methods;

[0032] FIG. 4 is an SEM photograph (40,000×) showing a 600 Å thick film on a 2000 Å topography applied according to the inventive methods;

[0033] FIG. 5 is an SEM photograph (35,000×) showing a 1500 Å thick film on a 1000 Å topography applied according to the inventive methods; and

[0034] FIG. 6 is an SEM photograph (70,000×) showing a 1500 Å thick film on a 2000 Å topography applied according to the inventive methods.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

EXAMPLES

[0035] The following examples set forth preferred methods in accordance with the invention. It is to be understood, however, that these examples are provided by way of illustration and nothing therein should be taken as a limitation upon the overall scope of the invention.

Example 1

[0036] Coatings (parylene-N, also known as 1,4-dixylylene or [2,2]-paracyclophane) were CVD polymerized on six- or eight-inch, flat silicon wafers, topography wafers, quartz slides, aluminum substrates, tantalum (Ta) substrates, and tantalum nitride (TaN) substrates. An initial eight runs on flat substrates were conducted to determine the best film thickness, optical properties, plasma etch rate, film uniformity, intermixing with photoresist, resistance to resist solvents, and adhesion to various substrates. The topography wafers were used to determine conformal properties. The film thickness was measured by ellipsometry at 25 points to estimate the mean thickness and 2σ standard error from which the thickness uniformity was derived. The thickness uniformity was determined by the following equation: 3$100·\frac{\begin{array}{c}\&LeftBracketingBar;\left(\mathrm{greatest}\mathrm{thickness}\mathrm{of}\mathrm{the}5\mathrm{measurements}\right)-\\ \left(\mathrm{smallest}\mathrm{thickness}\mathrm{of}\mathrm{the}5\mathrm{measurements}\right)\&RightBracketingBar;\end{array}}{\left(\mathrm{the}\mathrm{average}\mathrm{of}\mathrm{the}5\mathrm{thickness}\mathrm{measurements}\right).}$

[0037] This data is set forth in Table 1.

TABLE 1
Film Thickness Uniformity
	Mean Thickness	Standard	Thickness
Sample Number	(Å)	Deviation (Å)	Uniformity
63-52-1	1165	33.68	2.89%
63-56-1	1246	20.43	1.64%
63-47-1	1267	25.53	2.01%

[0038] Film conformality was tested by depositing poly(1,4-xylylene) on 1000 Å and 2000 Å topography wafers. An examination of an SEM photograph indicated that the film was nearly 100% conformal to the substrates over a topography of 1000 Å and 2000 Å in height.

[0039] The optical density was determined on coatings formed from the composition from above. The compositions were deposited on a quartz slide, and the absorbance was measured at 193 nm and 248 nm on a UV-vis spectrophotometer. This data is set forth in Table 2.

TABLE 2
Optical Properties
				optical	optical
Sample		248 nm	193 nm	density @	density @
Number	max	absorbance	absorbance	248 nm	193 nm
63-50-1	1.4032 @	0.1827	1.2210	1.53/um	10.19/um
	213 nm
63-57-1	1.890 @	0.2255	1.5865	1.76/um	12.38/um
	213 nm
Sample Number	na @ 193 nm	kb @ 193 nm
63-52-1	1.159 ± 0.004	0.489 ± 0.008
63-56-1	1.176 ± 0.007	0.477 ± 0.012
63-47-1	1.159 ± 0.002	0.507 ± 0.003
63-55-1	1.167 ± 0.005	0.513 ± 0.009
63-44-1	1.171 ± 0.006	0.529 ± 0.009
a“n” refers to the real component of the complex index of refraction which is calculated from “k”and “n”.
b“k” refers to the imaginary component of the complex index of refraction. “k” is a measurement of the absorption coefficient of a material and is dependant on wavelength.

[0040] The coating composition utilized gave an optical density which is considered effective for reducing substrate reflectivity over a wide range of film thicknesses (400-3000 Å). This is evidenced by the simulated substrate reflectivity vs. ARC thickness for the sample generated by Prolith/2 ver 4.0 using a k value of 0.40 and assuming that the ARC and photoresist real index of refraction are closely matched (see FIG. 1). In practical applications, the substrate reflectivity should be 5% or less. The coating composition utilized should be capable of controlling substrate reflectivity when the film thickness is greater than 400 Å.

[0041] Utilizing the composition, the interaction of the coating with a photoresist was determined. First, the film solubility in the photoresist solvent was determined by breaking each specimen into two pieces, with one piece being placed in ethyl lactate and the other piece being placed in propylene glycol monomethyl ether (common solvents for DUV photoresists). After 60 seconds of immersion, the samples were removed from the solvents and blown dry with nitrogen after which their respective final thicknesses were measured. A more than 5% swelling or thickness loss (relative to the starting thickness determined immediately after deposition) indicated poor resistance to photoresist solvents.

[0042] Also utilizing the composition, the coating was chemical vapor deposited on a silicon wafer as a film having a thickness of 1000 Å, followed by patterning of a photoresist (APEX-E®, available from Shipley) over the ARC and developing with MF-319 (available from Shipley). The wafers were cross-sectioned, and the resist features were examined with a scanning electron microscope. Good compatibility was indicated by the absence of any deformation at the bottom of the resist and particularly at the resist-ARC interface. The wafers showed little chemical interaction between the deposited ARC and the photoresist. Furthermore, the coating had very low solubility in the photoresist solvent (see Tables 3 and 4).

TABLE 3
Interlayer
Sample
Number	Initial Thickness	Final Thickness	Interlayer Estimate
63-50-1	1244 Å	1259 Å	14 Å (1.21%)

[0043]

TABLE 4
		Initial		Stripping
Sample Number	Solvent	Thickness	Final Thickness	Estimate
63-50-1	ethyl lactate	1255 Å	1247 Å	8 Å
63-50-1	PGMEA	1247 Å	1244 Å	3 Å

Example 2

[0044] Several runs were carried out depositing parylene-D on 8-inch, silicon wafers having varying feature heights. During these runs, the entire system was maintained under vacuum. The base pressure of 13-16 mTorr was maintained relatively constant throughout the process. First, the solid parylene was vaporized. The sublimation temperature profile comprised running a temperature gradient of from 85° C. to 100° C. over 2 hours and 25 minutes, followed by a temperature gradient of from 110° C. to 125° C. over a 10 minute time period, and finally maintaining the temperature at 125° C. for 5 minutes. The vaporized parylene was then transferred to a pyrolysis chamber where it was broken down into its monomeric units by being subjected to a temperature of about 650° C. for at least about 1 minute. The monomers were transferred to a deposition chamber wherein a silicon wafer was situated on a rotating shelf maintained at a speed of 2 rpm. The conditions in the chamber were ambient (about 25° C.), thus causing the monomers to polymerize and subsequently deposit as parylene on the substrate surfaces.

[0045] The foregoing process was repeated on several substrates having different feature heights and applying films of varying thicknesses. The SEM photographs of five of those samples are shown in FIGS. 2-6, respectively. Table 5 below shows the data obtained from each of the SEMs.

TABLE 5
Property
line:space ratio	1:1	1:1	1:1	1:2	1:1
line width	0.35 μm	0.25 μm	0.35 μm	0.35 μm	0.35 μm
step height	1000 Å	2000 Å	2000 Å	1000 Å	2000 Å
film thickness	600 Å	600 Å	600 Å	1500 Å	1500 Å
conformality	97%	95%	100%	93%	94%

Claims

1. A method of forming a precursor for use in manufacturing integrated circuits comprising the steps of: providing a quantity of an anti-reflective compound and a substrate having a surface onto which said compound is to be applied; subjecting said anti-reflective compound to a chemical vapor deposition process so as to deposit said anti-reflective compound in a layer on said substrate surface; and applying a photoresist layer to said anti-reflective compound layer to yield the circuit precursor.

2. The method of claim 1, wherein said anti-reflective compound comprises a polymer including a monomer comprising two cyclic moieties joined together by at least one alkyl group, wherein said alkyl group comprises from about 2-4 carbon atoms.

3. The method of claim 2, wherein at least one of said cyclic moieties is aromatic.

4. The method of claim 3, wherein said aromatic moieties are individually selected from the group consisting of benzene, naphthalene, anthracene, thiophene, furan, and pyrrole moieties.

5. The method of claim 4, wherein at least one of said aromatic moieties is benzene.

6. The method of claim 5, wherein said monomer is 1,4-dixylylene.

7. The method of claim 2, wherein said alkyl group is an ethyl group.

8. The method of claim 2, wherein the strain energy of said monomer is at least than about 10 kcal/mol.

9. The method of claim 1, wherein said substrate comprises a silicon wafer.

10. The method of claim 2, wherein said chemical vapor deposition process comprises the steps of: (a) subjecting said monomer to a sufficient temperature and pressure to form said monomer into a vapor; (b) cleaving the resulting vaporized monomer; and (c) depositing said cleaved monomer on said substrate surface.

11. The method of claim 10, wherein said subjecting step (a) is carried out at a temperature of from about 35-160° C. and a pressure of from about 2-50 mTorr.

12. The method of claim 10, wherein said cleaving step (b) comprises breaking a bond between two of the carbon atoms of said alkyl group.

13. The method of claim 10, wherein said cleaving step (b) comprises pyrolizing said monomer.

14. The method of claim 13, wherein said pyrolizing step comprises heating said monomer to a temperature of from about 580-700° C.

15. The method of claim 10, wherein said causing step (c) comprises subjecting said cleaved monomer to a temperature of from about 20-25° C.

16. The method of claim 1, wherein the anti-reflective compound layer on said substrate surface after said applying step has a thickness of from about 300-5000 Å.

17. The method of claim 1, wherein said anti-reflective compound layer is substantially insoluble in solvents utilized in said photoresist layer.

18. The method of claim 1, further including the steps of: exposing at least a portion of said photoresist layer to activating radiation; developing said exposed photoresist layer; and etching said developed photoresist layer.

19. The method of claim 1, wherein the anti-reflective compound layer deposited on said substrate surface absorbs at least about 90% of light at a wavelength of from about 150-500 nm.

20. The method of claim 1, wherein the anti-reflective compound layer deposited on said substrate surface will be subjected to light of a predetermined wavelength and has a k value of at least about 0.1 at said predetermined wavelength.

21. The method of claim 1, wherein the anti-reflective compound layer deposited on said substrate surface has a percent conformality of at least about 85%.

22. The method of claim 21, wherein said substrate comprises raised features and structure defining contact or via holes, and said subjecting step comprises depositing a quantity of said anti-reflective compound in a layer on said features and said hole-defining structure.

23. The method of claim 1, wherein said anti-reflective compound comprises a polymer including the monomer of Formula II.

24. A precursor structure formed during the course of the integrated circuit manufacturing process, said structure comprising: a substrate having a surface; a layer comprising an anti-reflective compound on said surface, said anti-reflective compound layer being formed on said surface by a chemical vapor deposition process; and a photoresist layer on said anti-reflective compound layer.

25. The structure of claim 24, wherein said anti-reflective compound comprises a polymer including a monomer comprising two cyclic moieties joined together by at least one alkyl group, said alkyl group comprising from 2-4 carbon atoms.

26. The structure of claim 25, wherein at least one of said cyclic moieties is aromatic.

27. The structure of claim 26, wherein said aromatic moieties are individually selected from the group consisting of benzene, naphthalene, anthracene, thiophene, furan, and pyrrole moieties.

28. The structure of claim 27, wherein at least one of said aromatic moieties is benzene.

29. The structure of claim 28, wherein said monomer is 1,4-dixylylene.

30. The structure of claim 25, wherein said alkyl group is an ethyl group.

31. The structure of claim 25, wherein the strain energy of said monomer is at least about 10 kcal/mol.

32. The structure of claim 24, wherein said substrate comprises a silicon wafer.

33. The structure of claim 25, wherein said chemical vapor deposition process by which said anti-reflective compound layer is formed comprises the steps of: (a) subjecting said monomer to a sufficient temperature and pressure to form said monomer into a vapor; (b) cleaving the resulting vaporized monomer; and (c) depositing said cleaved monomer on said substrate surface.

34. The structure of claim 33, wherein said subjecting step (a) is carried out at a temperature of from about 35-160° C. and a pressure of from about 2-50 mTorr.

35. The structure of claim 33, wherein said cleaving step (b) comprises breaking a bond between two of the carbon atoms of said alkyl group.

36. The structure of claim 33, wherein said cleaving step (b) comprises pyrolizing said monomer.

37. The structure of claim 36, wherein said pyrolizing step comprises heating said monomer to a temperature of from about 580-700° C.

38. The structure of claim 33, wherein said causing step (c) comprises subjecting said cleaved monomer to a temperature of from about 20-25° C.

39. The structure of claim 24, wherein the anti-reflective compound layer on said substrate surface has a thickness of from about 300-5000 Å.

40. The structure of claim 24, wherein said anti-reflective compound is substantially insoluble in solvents utilized in said photoresist layer.

41. The structure of claim 24, wherein the anti-reflective compound layer deposited on said substrate surface absorbs at least about 90% of light at a wavelength of from about 150-500 nm.

42. The structure of claim 24, wherein the anti-reflective compound layer deposited on said substrate surface will be subjected to light of a predetermined wavelength and has a k value of at least about 0.1 at said predetermined wavelength.

43. The structure of claim 24, wherein the anti-reflective compound layer deposited on said substrate surface has a percent conformality of at least about 85%.

44. The structure of claim 43, wherein said substrate comprises raised features and structure defining contact or via holes and said anti-reflective compound layer is deposited on said features and said hole-defining structure.

45. The structure of claim 24, wherein said anti-reflective compound comprises a polymer including the monomer of Formula II.