Neutralizing stress diamond-like carbon

Abstract

The present disclosure provides a method for processing a substrate. The method includes flowing a deposition gas comprising a hydrocarbon compound into a processing volume of a process chamber having a substrate positioned on an electrostatic chuck. Plasma is generated at a substrate by applying a first RF bias to an electrostatic chuck to deposit a diamond-like carbon film on the substrate. The diamond-like carbon film is doped with a hydrogen dopant to form a doped diamond-like carbon film. The hydrogen dopant is thermally annealed to the doped diamond-like carbon film.

Description

Background Technology Technical Field

[0002] The embodiments of this disclosure generally relate to the fabrication of integrated circuits. More specifically, the embodiments described herein provide techniques for depositing high-density films for patterning applications.

[0003] Related technical descriptions

[0004] Integrated circuits have evolved into complex devices that can include millions of transistors, capacitors, and resistors on a single chip. The continuous evolution of chip design demands faster circuit systems and greater circuit density. This need for faster circuits with greater circuit density places corresponding demands on the materials used to manufacture these integrated circuits. Specifically, as the size of integrated circuit components shrinks to the submicron level, it becomes necessary to use conductive materials with low resistivity and insulating materials with low dielectric constants to obtain appropriate electrical properties from these components.

[0005] The demand for higher integrated circuit density also places demands on the process sequences used to manufacture integrated circuit components. For example, in a process sequence using conventional photolithography, an energy-sensitive resist layer is formed on top of a stack of material layers disposed on a substrate. This energy-sensitive resist layer is exposed to a patterned image to form a photoresist mask. Subsequently, an etching process is used to transfer the mask pattern to one or more of the stacked material layers. The chemical etchant used in the etching process is selected to have greater etch selectivity for the stacked material layers than for the energy-sensitive resist mask. That is, the chemical etchant etches one or more layers of the material stack at a much faster rate than for the energy-sensitive resist. This etch selectivity for the stacked material layers compared to the resist prevents the energy-sensitive resist from being consumed before the pattern transfer is complete.

[0006] As pattern size decreases, the thickness of the energy-sensitive resist correspondingly decreases to control pattern resolution. These thin resist layers, due to their susceptibility to chemical etchants, may be insufficient to mask the underlying material layer during the pattern transfer step. An intermediate layer called a hard mask (e.g., silicon oxynitride, silicon carbide, or carbon film) is often used between the energy-sensitive resist layer and the underlying material layer, which facilitates pattern transfer due to its greater resistance to chemical etchants. Hard mask materials with high etch selectivity, high Young's modulus, and high deposition rate are required. As the critical dimension (CD) decreases, many current hard mask materials lack the required etch selectivity relative to the underlying material (e.g., oxides and nitrides), do not have high modulus, and are often difficult to deposit. Current hard mask materials with high etch selectivity, high modulus, and high deposition rate often have high stress levels (especially compressive stress), which can cause line wobble in the hard mask, leading to anomalies in integrated circuits.

[0007] Therefore, this technology requires an improved hard mask layer and a method for depositing the improved hard mask layer. Summary of the Invention

[0008] In one aspect, this disclosure provides a method for processing a substrate. The method includes flowing a deposition gas containing a hydrocarbon compound into a processing volume having a process chamber positioned on an electrostatic chuck. Plasma is generated at the substrate by applying a first RF bias voltage to the electrostatic chuck to deposit a diamond-like carbon film on the substrate. The diamond-like carbon film is doped with a hydrogen dopant to form a doped diamond-like carbon film. The hydrogen dopant is thermally annealed to the doped diamond-like carbon film.

[0009] In another aspect, this disclosure provides a method for processing a substrate. The method includes flowing a deposition gas containing a hydrocarbon compound and a hydrogen dopant into a processing volume having a substrate positioned on an electrostatic chuck. The processing volume is maintained at a pressure of about 0.5 mTorr to about 10 Torr. Plasma is generated at the substrate by applying a first RF bias voltage to the electrostatic chuck to deposit a doped diamond-like carbon film formed by the hydrocarbon compound and hydrogen dopant on the substrate. The hydrogen dopant is thermally annealed to the doped diamond-like carbon film.

[0010] In another aspect, this disclosure provides a method for processing a substrate. The method includes flowing a deposition gas containing a hydrocarbon compound and a hydrogen dopant into a processing volume having a process chamber on an electrostatic chuck. The electrostatic chuck includes a clamping electrode and an RF electrode separate from the clamping electrode. The processing volume is maintained at a pressure of about 0.5 mTorr to about 10 Torr. Plasma is generated at the substrate by applying a first RF bias voltage to the RF electrode to deposit a doped diamond-like carbon film formed by the hydrocarbon compound and hydrogen dopant on the substrate. The doped diamond-like carbon film has a density greater than 2.5 g / cc. The hydrogen dopant is thermally annealed to the doped diamond-like carbon film at a temperature of about 300°C to about 500°C for about 2 minutes to about 10 minutes, wherein the doped diamond-like carbon film has a substantially neutral stress. A patterned photoresist layer is formed on the doped diamond-like carbon film. The doped diamond-like carbon film is etched with a pattern corresponding to the patterned photoresist layer. The pattern is etched into the substrate. Attached Figure Description

[0011] To gain a more detailed understanding of the features described above in this disclosure, reference can be made to the implementations briefly outlined above, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only typical implementations of this disclosure and should not be construed as limiting the scope of this disclosure, as other equally effective implementations are permissible.

[0012] Figure 1A A schematic cross-sectional view is depicted showing a deposition system that can be used to practice the embodiments described herein.

[0013] Figure 1B A schematic cross-sectional view is depicted of another deposition system that can be used to practice the embodiments described herein.

[0014] Figure 2 A flowchart depicting a method for forming a doped diamond-like carbon film on a film stack disposed on a substrate, according to one or more embodiments of the present disclosure.

[0015] Figures 3A to 3B A sequence for forming a doped diamond-like carbon film on a film stack formed on a substrate is described according to one or more embodiments of the present disclosure.

[0016] Figure 4 A flowchart depicting a method of using a doped diamond-like carbon film according to one or more embodiments of the present disclosure.

[0017] For ease of understanding, common elements in the figures have been designated using the same element symbols where possible. It is contemplated that elements and features of one embodiment may be beneficially incorporated into other embodiments without further description. Detailed Implementation

[0018] The embodiments provided herein relate to doped diamond-like carbon films and methods for depositing or otherwise forming doped diamond-like carbon films on a substrate. In the following description and in... Figures 1A to 4 Certain details are set forth in this disclosure to provide a thorough understanding of the various embodiments thereof. Other details of well-known structures and systems often associated with plasma processing and the deposition of doped diamond-like carbon films are not set forth in the following disclosure to avoid unnecessarily obscuring the description of the various embodiments.

[0019] Many of the details, dimensions, angles, and other features shown in the figures are merely illustrative of particular embodiments. Therefore, other embodiments may have different details, components, dimensions, angles, and features without departing from the spirit or scope of this disclosure. Furthermore, other embodiments of this disclosure may be practiced without some of the details described below.

[0020] Current hard mask applications for memory and other devices primarily utilize thick carbon films (e.g., approximately 300 nm to approximately 1.5 μm), which are inherently amorphous. However, the etch selectivity of these films is insufficient to meet the increasingly demanding requirements of technology nodes and high aspect ratio etching. To achieve greater etch selectivity, improvements in film density and Young's modulus are needed.

[0021] One of the main challenges in achieving greater etch selectivity and an improved Young's modulus is the high compressive stress of this film, which makes it unsuitable for applications due to the resulting high wafer / substrate bending and line wobble. Therefore, a higher density and modulus (e.g., a larger sp) are required. 3 A carbon (e.g., diamond-like) film with high etch selectivity and reduced compressive stress.

[0022] The embodiments described herein include improved methods for fabricating doped diamond-like carbon films with high density (e.g., >2 g / cc), high modulus (e.g., >150 GPa), and low or neutral stress profiles. The doped diamond-like carbon films fabricated according to the various embodiments described herein are inherently amorphous and exhibit greater etch selectivity, higher modulus (e.g., >150 GPa), and lower stress (e.g., <200 MPa) than currently patterned films. Doped diamond-like carbon films can possess high sp... 3Carbon content. In general, the deposition process described in this paper is also fully compatible with current integrated solutions used in hard mask applications.

[0023] In one or more embodiments, the doped diamond-like carbon films described herein can be formed using a deposition gas containing one or more hydrocarbon compounds and one or more dopant compounds via chemical vapor deposition (CVD), such as plasma-enhanced CVD and / or thermal CVD processes. Exemplary hydrocarbon compounds may include acetylene or carbide gas (C2H2), propylene (C3H6), methane (CH4), butene (C4H8), 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene (2,5-norbornene), corundum (C4H8), etc. 10 H 16 norbornene (C7H) 10 ( ), its derivatives, its isomers, or any combination thereof.

[0024] The dopant compound may include one or more metal dopants, one or more non-metal dopants, or combinations thereof. The dopant compound may be one or more chemical precursors used in vapor deposition processes (such as CVD or ALD). Metal dopants may include one or more of tungsten, molybdenum, cobalt, nickel, vanadium, hafnium, zirconium, tantalum, or any combination thereof. Thus, metal dopants may include one or more of tungsten precursors, molybdenum precursors, cobalt precursors, nickel precursors, vanadium precursors, hafnium precursors, zirconium precursors, tantalum precursors, or any combination thereof. Exemplary metal dopants may include tungsten hexafluoride, tungsten hexacarbonyl, molybdenum pentachloride, cyclopentadienyldicarbonyl cobalt, hexacarbonylbutyryne dicobalt (CCTBA), di(cyclopentadienyl)cobalt, di(methylcyclopentadienyl)nickel, vanadium pentachloride, hafnium tetrachloride, tetra(dimethylamino)hafnium, tetra(diethylamino)hafnium, zirconium tetrachloride, di(cyclopentadienyl)zirconium dihydrogenide, tetra(dimethylamino)zirconium, tetra(diethylamino)zirconium, tantalum pentachloride, tantalum pentafluoride, penta(dimethylamino)tantalum, penta(diethylamino)tantalum, penta(ethylmethylamino)tantalum, their adducts, their derivatives, or any combination thereof. Non-metallic dopants may include one or more of boron, silicon, germanium, nitrogen, phosphorus, or any combination thereof. Thus, nonmetallic dopants may include one or more of boron precursors, silicon precursors, germanium precursors, nitrogen precursors, phosphorus precursors, or any combination thereof. Exemplary nonmetallic dopants may include disilane, diborane, triethylborane, silane, disilane, trisilane, germanium, ammonia, hydrazine, phosphine, their adducts, or any combination thereof.

[0025] In various embodiments, the substrate and processing volume may be heated and maintained at independent temperatures during the deposition process. The substrate and / or processing volume may be heated to temperatures of approximately -50°C, approximately -25°C, approximately -10°C, approximately -5°C, approximately 0°C, approximately 5°C, or approximately 10°C to approximately 15°C, approximately 20°C, approximately 23°C, approximately 30°C, approximately 50°C, approximately 100°C, approximately 150°C, approximately 200°C, approximately 300°C, approximately 400°C, approximately 500°C, or approximately 600°C. For example, the substrate and / or processing volume may be heated to temperatures of approximately -50°C to approximately 600°C, approximately -50°C to approximately 450°C, approximately -50°C to approximately 350°C, approximately -50°C to approximately 200°C, approximately -50°C to approximately 100°C, approximately -50°C to approximately 50°C, approximately -50°C to approximately 0°C, approximately 0°C to approximately 600°C, approximately 0°C to approximately 450°C, approximately 0°C to approximately 350°C, approximately 0°C to approximately 200°C, approximately 0°C to approximately 120°C, approximately 0°C to approximately 100°C, approximately 0°C to approximately 80°C, approximately 0°C to approximately 50°C, approximately 0°C to approximately 25°C, approximately 10°C to approximately 600°C, approximately 10°C to approximately 450°C, approximately 10°C to approximately 350°C, approximately 10°C to approximately 200°C, approximately 10°C to approximately 100°C, or approximately 10°C to approximately 50°C.

[0026] The processing volume of the processing chamber can be maintained at sub-atmospheric pressure during the deposition process. The processing volume of the processing chamber can be maintained at pressures of about 0.1 mTorr, about 0.5 mTorr, about 1 mTorr, about 5 mTorr, about 10 mTorr, about 50 mTorr, or about 80 mTorr to about 100 mTorr, about 250 mTorr, about 500 mTorr, about 1 Torr, about 5 Torr, about 10 Torr, about 20 Torr, about 50 Torr, or about 100 Torr. For example, the processing volume of the processing chamber can be maintained at a pressure of about 0.1 mTort to about 10 mTort, about 0.1 mTort to about 5 mTort, about 0.1 mTort to about 1 mTort, about 0.1 mTort to about 500 mTort, about 0.1 mTort to about 100 mTort, about 0.1 mTort to about 10 mTort, about 1 mTort to about 10 mTort, about 1 mTort to about 5 mTort, about 1 mTort to about 1 mTort, about 1 mTort to about 500 mTort, about 1 mTort to about 100 mTort, about 1 mTort to about 10 mTort, about 5 mTort to about 10 mTort, about 5 mTort to about 5 mTort, about 5 mTort to about 1 mTort, about 5 mTort to about 500 mTort, about 5 mTort to about 100 mTort, or about 5 mTort to about 10 mTort.

[0027] The deposition gas may further include one or more dilution gases, carrier gases, and / or purging gases, such as helium, argon, xenon, neon, nitrogen (N2), hydrogen (H2), or any combination thereof. The deposition gas may further include etchant gases such as chlorine (Cl2), carbon tetrafluoride (CF4), and / or nitrogen trifluoride (NF3) to improve film quality. Plasma (e.g., capacitively coupled plasma) may be formed from the top and bottom electrodes or side electrodes. These electrodes may be formed by a single-pass electrode, a dual-pass electrode, or more electrodes having multiple frequencies (such as, but not limited to, about 350 kHz, about 2 MHz, about 13.56 MHz, about 27 MHz, about 40 MHz, about 60 MHz, and about 100 MHz), used alternately or simultaneously with any or all of the reaction gases listed herein in a CVD system to deposit thin films of diamond-like carbon, as a hard mask and / or etch stop layer, or for any other application requiring a smooth carbon film. High etch selectivity of doped diamond-like carbon films is achieved by having a higher density and modulus than current-generation films. Without theoretical constraints, it is believed that the higher density and modulus may be due to the increased spp content in the doped diamond-like carbon films. 3 This is caused by the high content of hybrid carbon atoms, which can then be achieved through a combination of low voltage and low voltage power.

[0028] In one or more embodiments, a doped diamond-like carbon film can be deposited in a chamber in which a substrate substrate is maintained at about 10°C and a pressure maintained at about 2 mTorr, wherein plasma is generated at the substrate level by applying a bias voltage of about 2,500 watts (about 13.56 MHz) to an electrostatic chuck. In other embodiments, an additional RF of about 1,000 watts at about 2 MHz can also be supplied to the electrostatic chuck to generate a dual-biased plasma at the substrate level.

[0029] In one or more embodiments, a hydrogen dopant having one or more hydrogen radicals is fed in via RPS, which results in the sp 2 Selective etching of hybrid carbon atoms, thereby further improving sp in the film. 3 The proportion of hybridized carbon atoms further improves etching selectivity. Based on the total amount of carbon atoms in the doped diamond-like carbon film, the doped diamond-like carbon film can have a sp(t) ratio of at least 40 atomic percentages (at%), approximately 45 at%, approximately 50 at%, approximately 55 at%, or approximately 58 at% to approximately 60 at%, approximately 65 at%, approximately 70 at%, approximately 75 at%, approximately 80 at%, approximately 85 at%, approximately 88 at%, approximately 90 at%, approximately 92 at%, or approximately 95 at%. 3 The concentration or percentage of hybridized carbon atoms (e.g., sp). 3Hybridized carbon atom content). For example, based on the total amount of carbon atoms in the doped diamond-like carbon film, the doped diamond-like carbon film may have a sp(x) content of at least 40 at% to about 95 at%, about 45 at% to about 95 at%, about 50 at% to about 95 at%, about 50 at% to about 90 at%, about 50 at% to about 85 at%, about 50 at% to about 80 at%, about 50 at% to about 75 at%, about 50 at% to about 70 at%, about 50 at% to about 65 at%, about 65 at% to about 95 at%, about 65 at% to about 90 at%, about 65 at% to about 85 at%, about 65 at% to about 80 at%, about 65 at% to about 75 at%, about 65 at% to about 70 at%, about 65 at% to about 68 at%, about 75 at% to about 95 at%, about 75 at% to about 90 at%, about 75 at% to about 85 at%, about 75 at% to about 80 at%, or about 75 at% to about 78 at%. 3 The concentration or percentage of hybridized carbon atoms.

[0030] Based on the total amount of hydrogen atoms in the doped diamond-like carbon film, the doped diamond-like carbon film may have a concentration or percentage of hydrogen dopant of about 0.01 at%, about 0.05 at%, about 0.1 at%, about 0.3 at%, about 0.5 at%, about 0.8 at%, about 1 at%, about 1.2 at%, about 1.5 at%, about 1.8 at%, about 2 at%, about 2.5 at% or about 2.8 at% to about 3 at%, about 3.5 at%, about 4 at%, about 5 at%, about 6 at%, about 7 at%, about 8 at%, about 9 at%, about 10 at%, about 12 at%, about 15 at%, about 18 at%, about 20 at%, about 25 at%, about 30 at% or greater.For example, based on the total amount of hydrogen atoms in the doped diamond-like carbon film, the doped diamond-like carbon film may have the following concentrations or percentages of hydrogen dopant: about 0.01 at% to about 25 at%, about 0.1 at% to about 25 at%, about 0.5 at% to about 25 at%, about 1 at% to about 25 at%, about 2 at% to about 25 at%, about 3 at% to about 25 at%, about 5 at% to about 25 at%, about 5 at% to about 25 at%, about 10 at% to about 25 at%, about 12 at% to about 25 at%, about 15 at% to about 25 at%, about 18 at% to about 25 at%, about 20 at% to about 25 at%, about 0.1 at% to about 20 at%, about 0.5 at% to about 20 at%, about 1 at% to about 20 at%, about 2 at% to about 20 at%, about 3 at% to about 20 at%, about 5 at% to about 20 at%, about 7 at% to about 20 at%, about 10 at% to about 20 at%, about 12 at% to about 20 at%. at% to about 20 at%, about 15 at% to about 20 at%, about 18 at% to about 20 at%, about 0.1 at% to about 18 at%, about 0.5 at% to about 18 at%, about 1 at% to about 18 at%, about 2 at% to about 18 at%, about 3 at% to about 18 at%, about 5 at% to about 18 at%, about 7 at% to about 18 at%, about 10 at% to about 18 at%, about 12 at% to about 18 at%, about 15 at% to about 18 at%, about 0.1 at% to about 15 at%, about 0.5 at% to about 15 at%, about 1 at% to about 15 at%, about 2 at% to about 15 at%, about 3 at% to about 15 at%, about 5 at% to about 15 at%, about 7 at% to about 15 at%, about 10 at% to about 15 at%, about 12 at% to about 15 at%, about 0.01 at% to about 10 at%, about 0.1 at% to about 10 at%, about 0.5 at% to about 10 at%, about 1 at% to about 10 at%, about 2 at% to about 10 at%, about 3 at% to about 10 at%, about 4 at% to about 10 at%, about 5 at% to about 10 at%, about 7 at% to about 10 at%, about 0.01 at% to about 5 at%, about 0.1 at% to about 5 at%, about 0.5 at% to about 5 at%, about 1 at% to about 5 at%, about 2 at% to about 5 at%, or about 3 at% to about 5 at.

[0031] The doped diamond-like carbon film has a density greater than 2 g / cc, such as about 2.1 g / cc, about 2.2 g / cc, about 2.3 g / cc, about 2.4 g / cc, about 2.5 g / cc, about 2.6 g / cc, about 2.7 g / cc, about 2.8 g / cc, about 2.9 g / cc or about 3 g / cc to about 3.1 g / cc, about 3.2 g / cc, about 3.4 g / cc, about 3.5 g / cc, about 3.6 g / cc, about 3.8 g / cc, about 4 g / cc, about 4.5 g / cc, about 5 g / cc, about 5.5 g / cc, about 6 g / cc, about 6.5 g / cc, about 7 g / cc, about 8 g / cc, about 9 g / cc, about 10 g / cc, about 11 g / cc, about 12 g / cc or greater. For example, doped diamond-like carbon films have the following densities: greater than 2 g / cc to about 12 g / cc, greater than 2 g / cc to about 10 g / cc, greater than 2 g / cc to about 8 g / cc, greater than 2 g / cc to about 7 g / cc, greater than 2 g / cc to about 5 g / cc, greater than 2 g / cc to about 4 g / cc, greater than 2 g / cc to about 3 g / cc, greater than or about 2.5 g / cc to about 12 g / cc, greater than or about 2.5 g / cc to about 10 g / cc, greater than or about 2.5 g / cc to about 8 g / cc, greater than or about 2.5 g / cc to about 7 g / cc, greater than or about 2.5 g / cc to about 5 g / cc, greater than or about 2.5 g / cc to about 4 g / cc, greater than or about 2.5 g / cc to about 3 g / cc, greater than or about 3 g / cc to about 12 g / cc, greater than or about 3 g / cc to about 10 g / cc, greater than or about 3 g / cc to about 8 g / cc, greater than or about 3 ...12 g / cc, greater than or about 3 g / cc to about 10 g / cc, greater than or about 3 g / cc to about 8 g / cc, greater than or about 3 g / cc to about 12 g / cc, greater than or about 3 g / cc to about 10 g / cc, greater than or about 3 g / cc to about 10 g / cc, greater than or about 3 g / cc to about 10 g / cc, greater than or about g / cc to about 7 g / cc, greater than or about 3 g / cc to about 5 g / cc, greater than or about 3 g / cc to about 4 g / cc, or greater than or about 3 g / cc to about 3.5 g / cc.

[0032] The doped diamond-like carbon film can have a thickness of about 5 Å, about 10 Å, about 50 Å, about 100 Å, about 150 Å, about 200 Å or about 300 Å to about 400 Å, about 500 Å, about 800 Å, about 1,000 Å, about 2,000 Å, about 3,000 Å, about 5,000 Å, about 8,000 Å, about 10,000 Å, about 15,000 Å, about 20,000 Å or more. For example, doped diamond-like carbon films can have the following thicknesses: about 5 Å to about 20,000 Å, about 5 Å to about 10,000 Å, about 5 Å to about 5,000 Å, about 5 Å to about 3,000 Å, about 5 Å to about 2,000 Å, about 5 Å to about 1,000 Å, about 5 Å to about 500 Å, about 5 Å to about 200 Å, about 5 Å to about 100 Å, about 5 Å to about 50 Å, about 300 Å to about 20,000 Å, about 300 Å to about 10,000 Å, about 300 Å to about 5,000 Å, about 300 Å to about 3,000 Å, about 300 Å to about 2,000 Å, about 300 Å to about 1,000 Å, about 300 Å to about 500 Å, about 300 Å to about 500 Å, about 300 Å to about 20,000 Å, about 300 Å to about 1,0 ... Å to about 200 Å, about 300 Å to about 100 Å, about 300 Å to about 50 Å, about 1,000 Å to about 20,000 Å, about 1,000 Å to about 10,000 Å, about 1,000 Å to about 5,000 Å, about 1,000 Å to about 3,000 Å, about 1,000 Å to about 2,000 Å, about 2,000 Å to about 20,000 Å, or about 2,000 Å to about 3,000 Å.

[0033] Doped diamond-like carbon films may have a refractive index or n value greater than 2 (n (at 633 nm)), such as about 2.1, about 2.2, about 2.3, about 2.4 or about 2.5 to about 2.6, about 2.7, about 2.8, about 2.9 or about 3. For example, doped diamond-like carbon films may have a refractive index or n value greater than 2 to about 3, greater than 2 to about 2.8, greater than 2 to about 2.5, greater than 2 to about 2.3, about 2.1 to about 3, about 2.1 to about 2.8, about 2.1 to about 2.5, about 2.1 to about 2.3, about 2.3 to about 3, about 2.3 to about 2.8, or about 2.3 to about 2.5 (n (at 633 nm)).

[0034] Doped diamond-like carbon films may have an extinction coefficient or k-value (K (at 633 nm)) greater than 0.1, such as about 0.15, about 0.2, about 0.25, or about 0.3. For example, doped diamond-like carbon films may have an extinction coefficient or k-value (K (at 633 nm)) greater than 0.1 to about 0.3, greater than 0.1 to about 0.25, greater than 0.1 to about 0.2, greater than 0.1 to about 0.15, about 0.2 to about 0.3, or about 0.2 to about 0.25.

[0035] Doped diamond-like carbon films can have compressive stresses of less than or equal to 200 MPa, about 150 MPa or less, about 100 MPa or less, about 50 MPa or less, about 0 MPa or less, about -50 MPa or less, about -100 MPa or less, about -150 MPa or less, about -200 MPa or less, about -250 MPa or less, about -275 MPa or less, about -300 MPa or less, about -350 MPa or less, about -400 MPa or less, about -450 MPa or less, about -500 MPa or less, about -550 MPa or less, about -600 MPa or less. For example, doped diamond-like carbon films may have compressive stresses of about -600 MPa to about -300 MPa, about -600 MPa to about -350 MPa, about -600 MPa to about -400 MPa, about -600 MPa to about -450 MPa, about -600 MPa to about -500 MPa, about -600 MPa to about -550 MPa, about -550 MPa to about -300 MPa, about -550 MPa to about -350 MPa, about -550 MPa to about -400 MPa, about -550 MPa to about -450 MPa, about -550 MPa to about -500 MPa, about -500 MPa to about -300 MPa, about -500 MPa to about -350 MPa, about -500 MPa to about -400 MPa, or about -500 MPa to about -450 MPa.

[0036] Doped diamond-like carbon films can have an elastic modulus greater than 150 GPa, such as about 175 GPa, about 200 GPa or about 250 GPa to about 275 GPa, about 300 GPa, about 325 GPa, about 350 GPa, about 375 GPa or about 400 GPa. For example, doped diamond-like carbon films may have an elastic modulus of greater than 150 GPa to about 400 GPa, greater than 150 GPa to about 375 GPa, greater than 150 GPa to about 350 GPa, greater than 150 GPa to about 300 GPa, greater than 150 GPa to about 250 GPa, about 175 GPa to about 400 GPa, about 175 GPa to about 375 GPa, about 175 GPa to about 350 GPa, about 175 GPa to about 300 GPa, about 175 GPa to about 250 GPa, about 200 GPa to about 400 GPa, about 200 GPa to about 375 GPa, about 200 GPa to about 350 GPa, about 200 GPa to about 300 GPa, or about 200 GPa to about 250 GPa.

[0037] In some embodiments, the doped diamond-like carbon film serves as the underlayer for extreme ultraviolet (EUV) lithography. In some examples, the doped diamond-like carbon film serves as the underlayer for EUV lithography and has an sp3 hybridized carbon atom content of about 40% to about 90% based on the total amount of carbon atoms in the film, a density of greater than 2 g / cc to about 12 g / cc, and an elastic modulus of greater than or about 150 GPa to about 400 GPa.

[0038] Figure 1A A schematic diagram of a substrate processing system 132 according to an embodiment described herein is depicted, which can be used to perform doped diamond-like carbon film deposition. The substrate processing system 132 includes a process chamber 100 coupled to a gas distribution disk 130 and a controller 110. The process chamber 100 generally includes a top wall 124, side walls 101, and a bottom wall 122 defining a processing volume 126. A substrate support assembly 146 is disposed within the processing volume 126 of the process chamber 100. The substrate support assembly 146 generally includes an electrostatic chuck 150 supported by a rod 160. The electrostatic chuck 150 may be made of aluminum, ceramic, and / or other suitable materials thereof. A displacement mechanism (not shown) may be used to move the electrostatic chuck 150 vertically within the process chamber 100.

[0039] Vacuum pump 102 is coupled to a port formed in the bottom of process chamber 100. Vacuum pump 102 is used to maintain the required gas pressure in process chamber 100. Vacuum pump 102 also extracts processed gases and process byproducts from process chamber 100.

[0040] The substrate processing system 132 may further include additional devices for controlling chamber pressure, such as valves (e.g., throttle valves and isolation valves) positioned between the process chamber 100 and the vacuum pump 102 to control chamber pressure.

[0041] A gas distribution assembly 120 having multiple pores 128 is positioned on top of the process chamber 100, above the electrostatic chuck 150. The pores 128 of the gas distribution assembly 120 are used to introduce process gases (e.g., deposition gases, dilution gases, carrier gases, and purge gases) into the process chamber 100. The pores 128 may have different sizes, numbers, distributions, shapes, designs, and diameters to facilitate the flow of various process gases for different process requirements. The gas distribution assembly 120 is connected to a gas distribution disk 130, which allows the supply of various gases to the process volume 126 during processing. Plasma is formed by the process gas mixture exiting the gas distribution assembly 120 to enhance the thermal decomposition of the process gases, resulting in material deposition on the surface 191 of the substrate 190.

[0042] Gas distribution assembly 120 and electrostatic chuck 150 may form a pair of spaced-apart electrodes within processing volume 126. One or more RF power supplies 140 provide a bias potential to gas distribution assembly 120 via an optional matching network 138 to facilitate plasma generation between gas distribution assembly 120 and electrostatic chuck 150. Alternatively, RF power supply 140 and matching network 138 may be coupled to gas distribution assembly 120, electrostatic chuck 150, both gas distribution assembly 120 and electrostatic chuck 150, and / or coupled to an antenna (not shown) located outside process chamber 100. In one or more examples, RF power supply 140 may generate power at frequencies of about 350 kHz, about 2 MHz, about 13.56 MHz, about 27 MHz, about 40 MHz, about 60 MHz, or about 100 MHz. In some embodiments, RF power supply 140 may provide power from about 100 watts to about 3,000 watts at frequencies from about 50 kHz to about 13.6 MHz. In other embodiments, the RF power supply 140 can provide power of about 500 watts to about 1,800 watts at frequencies of about 50 kHz to about 13.6 MHz.

[0043] The controller 110 includes a central processing unit (CPU) 112, memory 116, and support circuitry 114 for controlling the process sequence and regulating airflow from the gas distribution pan 130. The CPU 112 can be any type of general-purpose computer processor suitable for industrial environments. Common software programs can be stored in memory 116, such as random access memory, read-only memory, floppy disk or hard disk drives, or other forms of digital storage. Support circuitry 114 is coupled to the CPU 112 and may include cache, clock circuitry, input / output systems, power supplies, and the like. Communication can be achieved via a plurality of signal cables collectively referred to as signal bus 118. Figure 1A Some of these are illustrated in the diagram to handle bidirectional communication between the controller 110 and various components of the substrate processing system 132.

[0044] Figure 1B A schematic cross-sectional view is depicted of another substrate processing system 180 that can be used to practice the embodiments described herein. The substrate processing system 180 may be similar to... Figure 1A The substrate processing system 132 differs from the substrate processing system 180 in that the substrate processing system 180 can be configured to allow processing gas from the gas distribution disk 130 to flow through the sidewall 101 across the surface 191 of the substrate 190. Additionally, electrodes 182 are used instead of... Figure 1A The gas distribution assembly 120 is depicted. Electrode 182 can be configured for secondary electron generation. In one or more embodiments, electrode 182 is a silicon-containing electrode.

[0045] Figure 2 A flowchart depicts a method 200 for forming a doped diamond-like carbon film on a film stack disposed on a substrate, according to one embodiment of the present disclosure. The doped diamond-like carbon film may, for example, be used as a hard mask to form a stepped structure in the film stack. Figures 3A to 3B This is a schematic cross-sectional view illustrating a sequence of doped diamond-like carbon films formed on a film stack disposed on a substrate according to method 200. Although method 200 is described below with reference to a hard mask layer (which can be formed on the film stack to create a stepped structure in the film stack for fabricating three-dimensional semiconductor devices), method 200 can also be used to leverage advantages in other device fabrication applications. Furthermore, it should be understood that... Figure 2 The operations described herein can be performed simultaneously and / or with Figure 2 The order described in the text is different from the order in which they are executed.

[0046] Method 200 begins at operation 210 with placing a substrate (such as, Figure 3A The substrate 302 depicted in the figure is positioned in the process chamber (such as, Figure 1A or Figure 1BThe substrate 302 can be located within the processing volume of the process chamber 100 depicted herein. Figure 1A and Figure 1B The substrate 190 is depicted in the figure. The substrate 302 can be positioned on an electrostatic chuck (e.g., the upper surface 192 of an electrostatic chuck 150). The substrate 302 may be a silicon-based material or any suitable insulating or conductive material (on which a film stack 304 is disposed), which can be used to form a structure 300, such as a stepped structure, in the film stack 304.

[0047] As in Figure 3A As depicted in the embodiments, substrate 302 may have a generally flat surface, a non-uniform surface, or a generally planar surface on which structures are formed. A film stack 304 is formed on substrate 302. In one or more embodiments, the film stack 304 may be used to form gate structures, contact structures, or interconnect structures in front-end or back-end processes. Method 200 may be performed on film stack 304 to form a stepped structure therein for use in memory structures (such as NAND structures). In one or more embodiments, substrate 302 may be a material such as crystalline silicon (e.g., Si). <100> or Si <111> Substrate 302 may include silicon oxide, strained silicon, silicon-germanium, doped or undoped polycrystalline silicon, doped or undoped silicon substrates and patterned or unpatterned substrates, silicon on insulator (SOI), carbon-doped silicon oxide, silicon nitride, doped silicon, germanium, gallium arsenide, glass, and sapphire. Substrate 302 may have various sizes, such as 200 mm, 300 mm, and 450 mm, or other diameters, and may be rectangular or square panels. Unless otherwise stated, the embodiments and examples described herein are performed on substrates having a diameter of 200 mm, 300 mm, or 450 mm. In embodiments where an SOI structure is used in substrate 302, substrate 302 may include an embedded dielectric layer disposed on a silicon substrate. In one or more embodiments depicted herein, substrate 302 may be a crystalline silicon substrate.

[0048] In one or more embodiments, the film stack 304 disposed on the substrate 302 may have a plurality of vertically stacked layers. The film stack 304 may include a first layer (shown as 308a1, 308a2, 308a3, ..., 308a) repeatedly formed in the film stack 304. n ) and the second layer (shown as 308b1, 308b2, 308b3, ..., 308b) n The pairing of ) may include repeatedly alternating formation of the first layer (shown as 308a1, 308a2, 308a3, ..., 308a) until the desired number of pairs of the first and second layers are reached.n ) and the second layer (shown as 308b1, 308b2, 308b3, ..., 308b) n ).

[0049] 304 film stacks can be part of semiconductor chips, such as three-dimensional memory chips. Although in Figures 3A to 3B The first layer is shown (denoted as 308a1, 308a2, 308a3, ..., 308a). n ) and the second layer (shown as 308b1, 308b2, 308b3, ..., 308b) n The three repeating layers of the first and second layers can be used, but note that any desired number of repeating pairs can be used in the first and second layers.

[0050] In one or more embodiments, a plurality of gate structures for a three-dimensional memory chip can be formed using the film stack 304. First layers 308a1, 308a2, 308a3, ..., 308a... are formed in the film stack 304. n It can be the first dielectric layer, and the second layer is 308b1, 308b2, 308b3, ..., 308b n It can be used as the second dielectric layer. It can be used to form the first layer 308a1, 308a2, 308a3, ..., 308a n The second layer 308b1, 308b2, 308b3, ..., 308b n Suitable dielectric layers include silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon oxycarbide, titanium nitride, oxide-nitride composites, at least one or more oxide layers sandwiched within a nitride layer, and combinations thereof, among others. In one or more embodiments, the dielectric layer may be a high-dielectric-constant material having a dielectric constant greater than 4. Suitable examples of high-dielectric-constant materials include hafnium oxide, zirconium oxide, titanium oxide, hafnium silicon oxide or hafnium silicate, hafnium aluminum oxide or hafnium aluminate, zirconium silicon oxide or zirconium silicate, tantalum oxide, aluminum oxide, aluminum-doped hafnium dioxide, bismuth strontium titanium (BST), and platinum zirconium titanium (PZT), dopants thereof, or any combination thereof.

[0051] In one or more examples, the first layer is 308a1, 308a2, 308a3, ..., 308a n The first layer is silicon oxide, and the second layer consists of layers 308b1, 308b2, 308b3, ..., 308b... n For installation on the first floor 308a1, 308a2, 308a3, ..., 308a nA silicon nitride layer or a polysilicon layer is applied. In one or more embodiments, each first layer 308a1, 308a2, 308a3, ..., 308a... n The thickness can be controlled from about 50 Å to about 1,000 Å, such as about 500 Å, and each second layer 308b1, 308b2, 308b3, ..., 308b n The thickness can be controlled from about 50 Å to about 1,000 Å, such as about 500 Å. The film stack 304 can have a total thickness from about 100 Å to about 2,000 Å. In one or more embodiments, the total thickness of the film stack 304 is from about 3 micrometers to about 10 micrometers, and can vary with technological advancements.

[0052] Please note that the diamond-like carbon film can be formed on any suitable surface or on any part of the substrate 302, regardless of whether the film stack 304 is present on the substrate 302.

[0053] Return to Figure 2 In method 200, at operation 220, a clamping voltage is applied to an electrostatic chuck, and substrate 402 is clamped or otherwise positioned on the electrostatic chuck. In one or more embodiments, with substrate 302 positioned on the upper surface 192 of the electrostatic chuck 150, the upper surface 192 provides support and clamps substrate 302 during processing. The electrostatic chuck 150 flattens substrate 302 to fit snugly against the upper surface 192 to prevent backside deposition. An electrical bias voltage is provided to substrate 302 via clamping electrodes. The clamping electrodes may be in electronic communication with a clamping power supply 212, which supplies a bias voltage to the clamping electrodes. In one or more embodiments, the clamping voltage is about 10 volts to about 3,000 volts, about 100 volts to about 2,000 volts, or about 200 volts to about 1,000 volts.

[0054] During operation 220, several process parameters can be adjusted. In some embodiments suitable for processing 300 mm substrates, the process pressure in the processing volume can be maintained at about 0.1 mTorr to about 10 mTorr (e.g., about 2 mTorr to about 50 mTorr; or about 5 mTorr to about 20 mTorr). In some embodiments suitable for processing 300 mm substrates, the processing temperature and / or substrate temperature can be maintained at about -50°C to about 350°C (e.g., about 0°C to about 50°C; or about 10°C to about 20°C).

[0055] In one or more embodiments, a constant clamping voltage is applied to the substrate 302. In some embodiments, the clamping voltage may be pulsed to the electrostatic chuck 150. In other embodiments, a back-side gas may be applied to the substrate 302 simultaneously with the clamping voltage to control the temperature of the substrate. The back-side gas may include, but is not limited to, helium, argon, neon, nitrogen (N2), hydrogen (H2), or any combination thereof.

[0056] At operation 230, plasma is generated at a substrate, such as horizontally adjacent to or near the substrate, by applying a first RF bias voltage to the electrostatic chuck. The plasma generated at the substrate can be generated in a plasma region between the substrate and the electrostatic chuck. The first RF bias voltage can range from about 10 watts to about 3,000 watts at frequencies from about 350 kHz to about 100 MHz (e.g., about 350 kHz, about 2 MHz, about 13.56 MHz, about 27 MHz, about 40 MHz, about 60 MHz, or about 100 MHz). In one or more embodiments, the first RF bias voltage is provided at a frequency of about 13.56 MHz with a power of about 2,500 watts to about 3,000 watts. In one or more embodiments, the first RF bias voltage is provided to the electrostatic chuck 150 via a second RF electrode. The second RF electrode can be in electronic communication with a first RF power supply that supplies a bias voltage to the second RF electrode. In one or more embodiments, the bias power is about 10 watts to about 3,000 watts, about 2,000 watts to about 3,000 watts, or about 2,500 watts to about 3,000 watts. The first RF power supply can generate power at frequencies from about 350 kHz to about 100 MHz (e.g., about 350 kHz, about 2 MHz, about 13.56 MHz, about 27 MHz, about 40 MHz, about 60 MHz, or about 100 MHz).

[0057] In one or more embodiments, operation 230 further includes applying a second RF bias to the electrostatic chuck. The second RF bias may range from about 10 watts to about 3,000 watts at frequencies ranging from about 350 kHz to about 100 MHz (e.g., about 350 kHz, about 2 MHz, about 13.56 MHz, about 27 MHz, about 40 MHz, about 60 MHz, or about 100 MHz). In some examples, the second RF bias is provided at a power of about 800 watts to about 1,200 watts at a frequency of about 2 MHz. In other examples, the second RF bias is provided to the substrate 302 via a clamping electrode. The clamping electrode may be in communication with a second RF power supply that supplies the bias voltage to the clamping electrode. In one or more examples, the bias power is about 10 watts to about 3,000 watts, about 500 watts to about 1,500 watts, or about 800 watts to about 1,200 watts. The second RF power supply can generate power at frequencies from about 350 kHz to about 100 MHz (e.g., about 350 kHz, about 2 MHz, about 13.56 MHz, about 27 MHz, about 40 MHz, about 60 MHz, or about 100 MHz). In one or more embodiments, the clamping voltage supplied in operation 220 is maintained during operation 230.

[0058] In some embodiments, during operation 230, a first RF bias is provided to substrate 302 via a clamping electrode, and a second RF bias may be provided to substrate 302 via a second RF electrode. In one or more examples, the first RF bias is about 2,500 watts (about 13.56 MHz), and the second RF bias is about 1,000 watts (about 2 MHz).

[0059] During operation 240, a deposition gas is flowed into processing volume 126 to form a diamond-like carbon film on the film stack. The deposition gas may flow into processing volume 126 from gas distribution disk 130 via gas distribution assembly 120 or via sidewall 101. The deposition gas may contain one or more hydrocarbon compounds and one or more dopant compounds. The hydrocarbon compounds may include one, two, or more hydrocarbon compounds in any state of matter. Similarly, the dopant compounds may include one, two, or more dopant compounds in any state of matter. The hydrocarbon compounds and / or dopant compounds may be any liquid or gas, but if either of the precursors is a gas or vapor at room temperature, several advantages are achieved, which simplifies the hardware required for metering, controlling, and delivering materials to the processing volume.

[0060] The deposition gas may further include inert gases, dilution gases, nitrogen-containing gases, etchant gases, or any combination thereof. In one or more embodiments, the clamping voltage supplied during operation 220 is maintained during operation 240. In some embodiments, the process conditions established during operation 220 and the plasma formed during operation 230 are maintained during operation 240.

[0061] In one or more embodiments, the hydrocarbon compound is a gaseous hydrocarbon or a liquid hydrocarbon. The hydrocarbon may include one or more alkanes, one or more alkenes, one or more alkynes, one or more aromatic hydrocarbons, or any combination thereof. In some examples, the hydrocarbon compound has the general formula C1. x H y Where x has a range of 1 to about 20, and y has a range of 1 to about 20. Suitable hydrocarbon compounds include, for example, C2H2, C3H6, CH4, C4H8, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene (2,5-norbornene), corundum (C 10 H 16 norbornene (C7H) 10 (or any combination thereof). In one or more examples, acetylene is utilized due to the formation of more stable intermediates (which allows for greater surface mobility).

[0062] Hydrocarbon compounds may include one or more alkanes (e.g., C42-C5 ... n H2n+2 (where n is from 1 to 20). Suitable hydrocarbon compounds include, for example, alkanes, such as methane (CH4), ethane (C2H6), propane (C3H8), and butane (C4H4). 10 ) and its isomers isobutane and pentane (C5H 12 ), hexane (C6H) 14 ) and its isomers isopentane and neopentane, hexane (C6H 14 ) and its isomers 2-methylpentane, 3-methylpentane, 2,3-dimethylbutane and 2,2-dimethylbutane or any combination thereof.

[0063] Hydrocarbon compounds may include one or more olefins (e.g., C40, C50, C60, C40, C6 ... n H 2n (where n is from 1 to 20). Suitable hydrocarbon compounds include, for example, alkenes, such as ethylene, propylene (C3H6), butene and its isomers, pentene and its isomers and their analogues, dienes (such as butadiene, isoprene, pentadiene, hexadiene) or any combination thereof. Additional suitable hydrocarbons include, for example, halogenated alkenes, such as monofluoroethylene, difluoroethylene, trifluoroethylene, tetrafluoroethylene, monochloroethylene, dichloroethylene, trichloroethylene, tetrachloroethylene or any combination thereof.

[0064] Hydrocarbon compounds may include one or more alkynes (e.g., C14, C2 ... n H 2n-2 (where n is from 1 to 20). Suitable hydrocarbons include, for example, alkynes, such as acetylene or carbide gas (C2H4), propyne (C3H4), butene (C4H8), vinylacetylene, or any combination thereof.

[0065] Hydrocarbon compounds may include one or more aromatic compounds, such as benzene, styrene, toluene, xylene, ethylbenzene, acetophenone, methyl benzoate, phenyl acetate, phenol, cresol, furan and its analogues, α-terpinene, umbelliferene, 1,1,3,3-tetramethylbutyroxene, tributyl ether, tributylethylene, methyl methacrylate and tributylfurfuryl ether, compounds having the formulas C3H2 and C5H4, halogenated aromatic compounds (including monofluorobenzene, difluorobenzene, tetrafluorobenzene, hexafluorobenzene) or any combination thereof.

[0066] Exemplary tungsten precursors may include tungsten hexafluoride, tungsten hexachloride, tungsten hexacarbonyl, bis(cyclopentadienyl)dihydrotungsten, bis(tributyl)bis(dimethylamine)tungsten, or any combination thereof. Exemplary molybdenum precursors may include molybdenum pentachloride, molybdenum hexacarbonyl, molybdenum dichloride, or any combination thereof. Exemplary cobalt precursors may include one or more of cobalt carbonyl compounds, cobalt ammonium salt compounds, cobalt dienyl compounds, cobalt dienyl compounds, their complexes, or any combination thereof. Exemplary cobalt precursors may include one or more of the following: cyclopentadienyl dicarbonyl cobalt (CpCo(CO)2), butynyl dicarbonyl hexacobalt (CCTBA), (cyclopentadienyl)(cyclohexadienyl)cobalt, (cyclobutadienyl)(cyclopentadienyl)cobalt, bis(cyclopentadienyl)cobalt, bis(methylcyclopentadiene)cobalt, bis(ethylcyclopentadiene)cobalt, cyclopentadiene(1,3-hexadiene)cobalt, (cyclopentadiene)(5-methylcyclopentadiene)cobalt, and bis(ethylene)(pentamethylcyclopentadiene)cobalt.

[0067] Exemplary nickel precursors may include bis(cyclopentadienyl)nickel, bis(ethylcyclopentadienyl)nickel, bis(methylcyclopentadienyl)nickel, allyl(cyclopentadienyl)nickel, or any combination thereof. Exemplary vanadium precursors may include vanadium pentachloride, bis(cyclopentadiene)vanadium, or any combination thereof. Exemplary zirconium precursors may include zirconium tetrachloride, bis(cyclopentadiene)zirconium dihydrogenide, tetra(dimethylamino)zirconium, tetra(diethylamino)zirconium, or any combination thereof.

[0068] Hafnium precursors may include one or more cyclopentadienyl hafnium compounds, one or more amino hafnium compounds, one or more alkyl hafnium compounds, one or more alkoxy hafnium compounds, their substitutes, their complexes, their adducts, their salts, or any combination thereof. Exemplary hafnium precursors may include bis(methylcyclopentadienyl)dimethylhafnium ((MeCp)2HfMe2), bis(methylcyclopentadienyl)methylmethoxyhafnium ((MeCp)2Hf(OMe)(Me)), bis(cyclopentadienyl)dimethylhafnium ((Cp)2HfMe2), tetra(tert-butoxy)hafnium, isopropoxide hafnium ((iPrO)4Hf), tetra(dimethylamino)hafnium (TDMAH), tetra(diethylamino)hafnium (TDEAH), tetra(ethylmethylamino)hafnium (TEMAH), their isomers, their complexes, their adducts, their salts, or any combination thereof.

[0069] Exemplary tantalum-containing compounds may include penta(ethylmethylamino)tantalum (PEMAT), penta(diethylamino)tantalum (PDEAT), penta(dimethylamino)tantalum (PDMAT), and any derivatives of PEMAT, PDEAT, and PDMAT. Exemplary tantalum-containing compounds also include tributyliminotri(diethylamino)tantalum (TBTDET), tributyliminotri(dimethylamino)tantalum (TBTDMT), bis(cyclopentadienyl)tantalum trihydrogenate, bis(methylcyclopentadienyl)tantalum trianide, and tantalum halide TaX5, wherein X is fluorine (F), bromine (Br), or chlorine (Cl) and / or derivatives thereof. Exemplary nitrogen-containing compounds include nitrogen, ammonia, hydrazine, methylhydrazine, dimethylhydrazine, tributylhydrazine, phenylhydrazine, azoisobutane, ethylhydrazine, and derivatives thereof.

[0070] Exemplary silicon precursors may include silanes, disilanes, trisilanes, tetrasilanes, pentasilanes, hexasilanes, monochlorosilanes, dichlorosilanes, trichlorosilanes, tetrachlorosilanes, hexachlorosilanes, substituted silanes, their plasma derivatives, or any combination thereof. Exemplary boron precursors may include diboranes, triboranes, tetraboranes, triethylborane (Et3B), dimethylaminoboranes, or any combination thereof.

[0071] Nitrogen-containing compounds may include one or more of pyridine compounds, aliphatic amines, amines, nitriles, and similar compounds. Exemplary nitrogen-containing compounds may include nitrogen gas, atomic nitrogen, ammonia, hydrazine, methylhydrazine, dimethylhydrazine, tributylhydrazine, phenylhydrazine, azoisobutane, ethylhydrazine, pyridine, and derivatives thereof. Exemplary phosphorus precursors may include phosphine, triphenylphosphine, trimethylphosphine, triethylphosphine, or any combination thereof. Exemplary germanium precursors may include germanane, tetramethylgermanium, triethylgermanium hydrogenate, triphenylgermanium hydrogenate, or any combination thereof.

[0072] In one or more embodiments, the deposition gas further comprises one or more diluent gases, one or more carrier gases, and / or one or more purging gases. Suitable diluent gases, carrier gases, and / or purging gases, such as helium (He), argon (Ar), xenon (Xe), hydrogen (H2), nitrogen (N2), ammonia (NH3), nitric oxide (NO), or any combination thereof, and other suitable diluent gases, may be co-flowed with the deposition gas or otherwise supplied to the processing volume 126. Argon, helium, and / or nitrogen can be used to control the density and deposition rate of the diamond-like carbon film. In some cases, the addition of N2 and / or NH3 can be used to control the hydrogen ratio of the diamond-like carbon film, as discussed below. Alternatively, diluent gases may not be used during deposition.

[0073] In some embodiments, the deposition gas further contains an etchant gas. Suitable etchant gases may include chlorine (Cl2), fluorine (F2), hydrogen fluoride (HF), carbon tetrafluoride (CF4), nitrogen trifluoride (NF3), or any combination thereof. Without being bound by theory, it is believed that the etchant gas selectively etches the film from the sp. 2 Hybridized carbon atoms increase the sp atoms in the membrane. 3 The proportion of hybrid carbon atoms increases the etching selectivity of the film.

[0074] At operation 250, after the diamond-like carbon film 312 is formed on the substrate during operation 240, the diamond-like carbon film 312 is exposed to a hydrogen dopant having one or more hydrogen radicals. In some embodiments, the diamond-like carbon film is exposed to hydrogen radicals during the deposition process of operation 240. Hydrogen radicals may form in the RPS and be transported to the processing area. Without being bound by theory, it is believed that exposing the diamond-like carbon film to hydrogen radicals can lead to sp 2 Selective etching of hybrid carbon atoms, thereby increasing the spt of the film. 3 Hybrid carbon atoms are proportionally increased and etching selectivity is enhanced.

[0075] At operation 260, the doped diamond-like carbon film is thermally annealed with a hydrogen dopant. In some embodiments, the thermal annealing may include temperatures from about 300 degrees Celsius to about 500 degrees Celsius, such as about 400 degrees Celsius. The thermal annealing may last from about 2 minutes to about 10 minutes, such as about 5 minutes. In some embodiments, thermal annealing of the diamond-like carbon film increases compressive stress, which can lead to increased line wobble problems. Without being bound by theory, it is believed that thermal annealing of the doped diamond-like carbon film with a hydrogen dopant reduces the compressive stress in the diamond-like carbon film. Exposing the film to hydrogen radicals to incorporate hydrogen into the carbon network relay via hydrogen doping causes the film to relax and reduce the compressive stress naturally present in the diamond-like carbon film. In some embodiments, hydrogen doping of the diamond-like carbon film results in substantially neutral stresses in the diamond-like carbon film (e.g., from about -100 MPa to about 100 MPa). In other embodiments, hydrogen doping of the diamond-like carbon film results in tensile stresses. The amount of stress reduction is directly related to the hydrogen doping level, which can be controlled by the carbon and hydrogen precursor flow rates, plasma power, chamber pressure, and / or chamber temperature.

[0076] At operation 270, after forming a doped diamond-like carbon film 312 on the substrate, the substrate is released from its clamping position. During operation 270, the clamping voltage may be turned off. The reactive gas is shut off and, if necessary, purged from the processing chamber. In one or more embodiments, during operation 270, the RF power is reduced (e.g., reduced to approximately 200 watts). If necessary, controller 110 monitors impedance changes to determine whether electrostatic charge dissipates to ground via the RF path. Once the substrate is released from the electrostatic chuck, any remaining gas is purged from the processing chamber. The processing chamber is evacuated, and the substrate is moved upwards on a lifting rod and removed from the chamber.

[0077] Figure 4 A flowchart depicts a method 400 using a doped diamond-like carbon film according to one or more embodiments described and discussed herein. After the doped diamond-like carbon film 312 is formed on a substrate, the doped diamond-like carbon film 312 can be used as a patterning mask in an etching process to form a three-dimensional structure, such as a stepped structure. The doped diamond-like carbon film 312 can be patterned using standard photoresist patterning techniques.

[0078] At operation 410, a patterned photoresist (not shown) can be formed on the doped diamond-like carbon film 312. At operation 420, the doped diamond-like carbon film 312 can be etched with a pattern corresponding to the patterned photoresist layer, and then the pattern is etched into the substrate 302 at operation 430. At operation 440, material can be deposited into the etched portion of the substrate 302. At operation 450, the doped diamond-like carbon film 312 can be removed using a solution containing hydrogen peroxide and sulfuric acid. An exemplary solution containing hydrogen peroxide and sulfuric acid is referred to as a piranha solution or piranha etchant. The doped diamond-like carbon film 312 can also be removed using etching chemicals containing oxygen and halogens (e.g., fluorine or chlorine) (e.g., Cl2 / O2, CF4 / O2, Cl2 / O2 / CF4). The doped diamond-like carbon film 312 can be removed by a chemical mechanical polishing (CMP) process.

[0079] Therefore, methods and apparatus are provided for forming a hard mask layer, which is or contains a doped diamond-like carbon film, which can be used to form a stepped structure for fabricating a three-dimensional stack of semiconductor devices. By utilizing a doped diamond-like carbon film as a hard mask layer with desired robust film properties and etch selectivity, for example in applications implementing three-dimensional stacking of semiconductor devices, improved size and profile control of the resulting structure formed in the film stack can be obtained, and the electrical performance of the chip device can be enhanced.

[0080] In summary, some of the benefits of this disclosure provide processes for depositing or otherwise forming doped diamond-like carbon (DLC) films on substrates and for thermally annealing doped DLC films. Typical PE-CVD hard mask films (such as DLC films) have high compressive stress. By using hydrogen-doped DLC films and thermally annealing the hydrogen dopant to the doped DLC film, a reduced stress distribution, such as a neutral stress distribution or even a tensile stress distribution, is achieved. This neutral or tensile stress distribution reduces line wobble problems, which in turn helps to eliminate anomalies in integrated circuits.

[0081] Although the foregoing describes embodiments of this disclosure, other and further embodiments are contemplated without departing from the essential scope of this disclosure, which is defined by the appended claims. All documents described herein are incorporated by reference, including any priority documents and / or test procedures, up to the extent that they are inconsistent with this text. As is clear from the foregoing general description and specific embodiments, while various forms of this disclosure have been illustrated and described, various modifications may be made without departing from the spirit and scope of this disclosure. Therefore, it is not intended to limit this disclosure. Similarly, the term “comprising” is considered synonymous with the term “including” for patent law purposes. Likewise, whenever the transitional phrase “comprising” precedes a composition, an element, or a group of elements, it should be understood that the composition, an element, or multiple elements are also contemplated with the transitional phrases “substantially composed of,” “composed of,” “selected from a group of,” or “is,” and vice versa. As used herein, the term “about” refers to a range within + / - 10% of a value.

[0082] Certain embodiments and features have been described using a set of upper numerical limits and a set of lower numerical limits. It should be understood that, unless otherwise indicated, the range includes any combination of two values; for example, any combination of a lower limit value and any upper limit value, any combination of two lower limit values, and / or any combination of two upper limit values ​​are also contemplated. Certain lower limit values, upper limit values, and ranges appear in the appended claims.

Claims

1. A method for processing a substrate, comprising: The deposition gas, including hydrocarbon compounds, is flowed into the processing volume of a process chamber having a substrate positioned on an electrostatic chuck. as well as Plasma is generated at the substrate by applying a first RF bias voltage to the electrostatic chuck to deposit a diamond-like carbon film on the substrate. The diamond-like carbon film is doped with a hydrogen dopant to form a doped diamond-like carbon film; as well as The hydrogen dopant is thermally annealed to the doped diamond-like carbon film.

2. The method of claim 1, wherein the doped diamond-like carbon film has a density greater than or equal to about 2.5 g / cc.

3. The method of claim 1, wherein the doped diamond-like carbon film comprises a stress distribution of about -100 MPa to about 100 MPa.

4. The method of claim 1, wherein the doped diamond-like carbon film has an atomic percentage of hydrogen ranging from about 0.01 atomic percentage to about 30 atomic percentage.

5. The method of claim 1, wherein the hydrogen dopant comprises at least one of H2.

6. The method of claim 1, wherein the hydrocarbon compound comprises at least one of acetylene, propylene, methane, butene, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene, corundum, or norbornene.

7. The method of claim 1, wherein the deposition gas further comprises helium, argon, xenon, neon, nitrogen (N2), hydrogen (H2), or any combination thereof.

8. The method of claim 1, wherein the processing volume is maintained at a pressure of about 5 mTorr to about 100 mTorr.

9. The method of claim 1, wherein the doped diamond-like carbon film has an elastic modulus greater than 150 GPa.

10. The method of claim 1, wherein thermal annealing of the doped diamond-like carbon film comprises: The processing chamber is heated to a temperature of approximately 300 degrees Celsius to approximately 500 degrees Celsius.

11. The method of claim 1, wherein the thermal annealing of the doped diamond-like carbon film is performed for about 2 minutes to about 10 minutes.

12. A method for processing a substrate, comprising: A deposition gas comprising hydrocarbon compounds and hydrogen dopants is flowed into a processing volume of a process chamber having a substrate positioned on an electrostatic chuck, wherein the processing volume is maintained at a pressure of about 0.5 mTorr to about 10 Torr. Plasma is generated at the substrate by applying a first RF bias voltage to the electrostatic chuck to deposit a doped diamond-like carbon film formed by the hydrocarbon compound and the hydrogen dopant on the substrate. as well as The hydrogen dopant is thermally annealed to the doped diamond-like carbon film.

13. The method of claim 12, wherein the doped diamond-like carbon film has an atomic percentage of hydrogen ranging from about 0.01 atomic percent to about 30 atomic percent.

14. The method of claim 12, wherein the doped diamond-like carbon film comprises a stress distribution of about -100 MPa to about 100 MPa.

15. The method of claim 12, wherein the hydrocarbon compound comprises at least one of acetylene, propylene, methane, butene, 1,3-dimethyladamantane, bicyclo[2.2.1]hept-2,5-diene, corundum, or norbornene.

16. The method of claim 12, wherein the deposition gas further comprises at least one of helium, argon, xenon, neon, nitrogen (N2) or hydrogen (H2).

17. The method of claim 12, wherein the doped diamond-like carbon film has an elastic modulus greater than 150 GPa.

18. The method of claim 12, wherein the thermal annealing of the doped diamond-like carbon film is performed for about 2 minutes to about 10 minutes.

19. A method for processing a substrate, comprising: A deposition gas comprising hydrocarbon compounds and hydrogen dopants is flowed into a process volume having a substrate positioned on an electrostatic chuck, wherein the electrostatic chuck includes a clamping electrode and an RF electrode separate from the clamping electrode, wherein the process volume is maintained at a pressure of about 0.5 mTorr to about 10 Torr. Plasma is generated at the substrate by applying a first RF bias voltage to the RF electrode to deposit a doped diamond-like carbon film formed by the hydrocarbon compound and the hydrogen dopant on the substrate, wherein the doped diamond-like carbon film has a density greater than 2.5 g / cc. The hydrogen dopant is thermally annealed to the doped diamond-like carbon film at a temperature of about 300 degrees Celsius to about 500 degrees Celsius for about 2 minutes to about 10 minutes, wherein the doped diamond-like carbon film has a generally neutral stress. A patterned photoresist layer is formed on the doped diamond-like carbon film; The doped diamond-like carbon film is etched using a pattern corresponding to the patterned photoresist layer; as well as The pattern is etched into the substrate.

20. The method of claim 19, wherein the doped diamond-like carbon film has an elastic modulus greater than 150 GPa.

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