Film formation via pulsed RF plasma.

Abstract

Systems and methods using pulsed RF plasma to form amorphous and microcrystalline films are discussed herein. The method of forming films includes (a) forming a plasma in a processing chamber from a film precursor, and (b) pulsing the RF power source to vary the duty cycle on time (T) of the duty cycle of the pulses generated by the RF power source. ON ) to the total cycle time (T TOT (c) depositing a first film interlayer on the substrate in the processing chamber; (d) purging the processing chamber following (c); and (e) introducing a hydrogen plasma into the processing chamber following (d). The method further includes repeating (b) through (e) to form the film. The film may have an in-film hydrogen content of less than about 10%.

Description

[Technical field]

[0001] TECHNICAL FIELD

[0001] Embodiments of the present disclosure generally relate to the deposition of thin films on substrates, such as semiconductor substrates and hardware components. [Background technology]

[0002]

[0002] Plasma enhanced chemical vapor deposition (PECVD) can be used to form films, including silicon and hydride films, during semiconductor device fabrication. High hydrogen (H) content in such films can lead to integration problems when subsequent films are formed on top of the PECVD-formed film. Integration problems can include film delamination and bubbling, and migration of hydrogen in the film to other layers. The deposition temperature can be modulated during PECVD deposition of thin films to change the hydrogen content of the film, but high deposition temperatures utilize an amount of energy that can exceed the thermal budget of semiconductor manufacturing operations.

[0003]

[0003] Thus, there remains a need in the art for improved methods of forming thin films on semiconductor substrates and hardware components. Summary of the Invention

[0004]

[0004] A method and system for forming a film using RF pulsed plasma is discussed herein. In one aspect, the method for forming a film includes ionizing a precursor to form a plasma in a process volume of a processing chamber, and pulsing an RF power source coupled to the processing chamber. In response to pulsing the RF power, a film is deposited on a substrate disposed on a substrate support inside the processing volume during the pulsing of the RF power, and the film includes less than about 10% hydrogen content.

[0005]

[0005] Implementations may include one or more of the following: The substrate support may be at a temperature of 350°C to 450°C during deposition of the film. Introducing the precursor gas may include introducing the precursor gas through a gas distribution assembly opposite the substrate support, the gas distribution assembly being at a temperature of about 200°C to about 350°C during deposition of the film. The film may be deposited at a deposition rate of 1 Å / sec to 8 Å / sec while pulsing the RF power source. Pulsing the RF power source may include a duty cycle on time (T) of the RF power source of less than about 20%. ON The precursor gas may include silicon (Si) or germanium (Ge). The precursor gas may include hydrogen. The precursor gas may include C2H6, C2H2, or GeH4.

[0006] In another aspect, a method of forming a film includes introducing a precursor gas into a process space of a process chamber having a chamber lid, a chamber bottom, and a sidewall extending therebetween, and ionizing the precursor gas to form a plasma. The RF power source has a duty cycle on time (T ON ) to the total cycle time (T TOT ) to less than about 20% to deposit a film having a hydrogen content of less than about 10%.

[0007]

[0007] Implementations may include one or more of the following: A duty cycle on time (T ON ) is the total cycle time of the duty cycle (T TOT ) is less than about 10%. The film may include a hydrogen content of less than about 5%. The film may have a thickness variation of less than about 6%. The film may be deposited on a substrate disposed on a substrate support in a processing chamber. The film may be deposited on at least one of a chamber lid, a chamber bottom, and a sidewall of the processing chamber. Deposition of the film may occur at a deposition rate of about 1 Å / min to about 10 Å / min.

[0008] In another aspect, a method of forming a film includes: (a) forming a plasma in a process chamber from a film precursor; and (b) pulsing an RF power source to vary the duty cycle on time (T ON ) to the total cycle time (T TOT (c) depositing a first film interlayer on the substrate in the processing chamber; (d) purging the processing chamber subsequent to (c); and (e) introducing a hydrogen plasma into the processing chamber subsequent to (d). The method further includes repeating (b) through (e) to form a film.

[0009]

[0009] The embodiments may include one or more of the following: The substrate may include at least one of a lid surface of the processing chamber, a bottom surface of the processing chamber, a sidewall of the processing chamber, or a substrate disposed on a substrate support in the processing chamber. The film deposition rate in (c) may be about 1 Å / min to about 5 Å / min. The thickness of the first film interlayer may be about 2 Å to about 50 Å. The thickness of the film may be about 100 Å to about 500 Å.

[0010] In another aspect, a non-transitory computer-readable medium stores instructions that, when executed by a processor, cause the process to perform the operations of the apparatus and / or methods described above.

[0011]

[0011] So that the above features of the present disclosure can be understood in detail, a more particular description of the present disclosure briefly summarized above may be had by reference to the embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings show only exemplary embodiments and therefore should not be considered as limiting the scope thereof, which may admit of other equally effective embodiments. [Brief description of the drawings]

[0012] [Figure 1]1 is a schematic diagram of a substrate processing system according to an embodiment of the present disclosure. [Diagram 2]

[0013] 1 is a flow chart of a method for forming a film using a pulsed RF plasma according to an embodiment of the present disclosure. [Diagram 3]

[0014] 1 is a flow chart of another method of forming a film using a pulsed RF plasma according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013]

[0015] To facilitate understanding, the same reference numerals have been used, where possible, to designate identical elements common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0014]

[0016] The following disclosure relates generally to substrate processing systems, and more particularly to apparatus and methods for depositing films using pulsed RF plasma. Certain details are set forth in the following description and in Figures 1-3 to provide a comprehensive understanding of various embodiments of the present disclosure. Other details describing well-known structures and systems often associated with optical detection and substrate placement are not set forth in the following disclosure to avoid unnecessarily obscuring the description of the various embodiments.

[0015]

[0017] Many of the details, dimensions, angles, and other features shown in the figures are merely illustrative of particular embodiments. Thus, other embodiments may have other details, components, dimensions, angles, and features without departing from the spirit or scope of the present disclosure. Further embodiments of the present disclosure may be practiced without some of the details described below. Additionally, the descriptions of the devices described herein are illustrative and should not be understood or interpreted as limiting the scope of the embodiments described herein.

[0016]

[0018] Semiconductor devices may include silicon-containing, nitride-containing, and hydride-containing thin films. The same types of thin films may also be used to coat and protect processing chamber parts in which semiconductor devices are fabricated. Processing chambers may be configured to perform operations including chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), atomic layer deposition (ALD), or physical vapor deposition (PVD). Thin film quality on substrates or chamber parts may be adversely affected by in-film impurities such as high hydrogen content, e.g., in-film hydrogen content of 10% or more. When thin films are used to coat processing chamber parts, poor film quality of the protective coating may lead to delamination of the protective coating and contamination of the substrate placed in the processing chamber. In another example, when a thin film is formed on a substrate of a semiconductor device, poor film quality may cause downstream operation problems, fragmentation, or reduced device performance. High in-film hydrogen content may adversely affect film quality and overall device quality. For example, a film layer subsequently formed over a poor quality film layer may experience other quality issues including adhesion or migration of in-film hydrogen content. In another example, the underlayer on which the film is formed may experience quality issues including migration of the hydrogen content within the film to the underlayer.

[0017]

[0019] Using the systems and methods discussed herein, RF power is pulsed during plasma enhanced chemical vapor deposition (PECVD) during film formation on a substrate or chamber component. The formed film may include an amorphous silicon film, an amorphous carbon film, or a microcrystalline film of silicon or other materials. In one example, pulsing the RF power during film deposition forms a film having a predetermined in-film hydrogen content. In one example, the in-film hydrogen content is less than 10%, e.g., in the range of about 1% to about 9%. In another example, the in-film hydrogen content is less than 5%, e.g., in the range of about 1% to about 4%. In yet another example, the in-film hydrogen content is less than 2%, e.g., in the range of about 0.1% to about 1%. Each pulse of RF power is a period of "on time" (T) during which the RF power is on. ON ) and the "off time" when the power is off (TOFF ) is the sum of the total time (T TOT ) is included. ON and T OFF Each of the T ON and T OFF The duty cycle of the pulses of RF power during PECVD film formation may be defined as the percentage of the duty cycle where the sum of T ON In one example, during PECVD film formation, the duty cycle of the pulses of RF power can be adjusted to be less than 20%, 15%, 10%, or 5%. ON In another example, during PECVD film formation, the duty cycle of the pulses of RF power can be adjusted to have a duty cycle T ON In yet another example, during PECVD film formation, the duty cycle of the pulses of RF power can be adjusted to have a T ON In yet another example, during PECVD film formation, the duty cycle of the pulses of RF power can be adjusted to have a T ON The hydrogen content in the membrane can be adjusted to be less than 5%, for example, from about 1% to about 4%. Without being bound by theory, it is believed that the hydrogen content in the membrane can be further reduced by replacing the helium diluent gas with a hydrogen diluent gas.

[0018]

[0020] In some examples, the substrate can be heated before and / or during the pulsed RF plasma film deposition. The substrate can be heated using heat lamps arranged around the substrate support on which the substrate is disposed. In another example, the substrate can be heated using heating elements included in the substrate support. In one embodiment, the pulsed RF plasma film deposition is performed while the substrate is at a temperature of 300° C. to 500° C., e.g., 350° C. to 450° C. In one example, which can be combined with other examples, the pressure in the chamber during deposition is at least 8 Torr, e.g., about 8 Torr to about 20 Torr, such as about 8 Torr to about 15 Torr. Additionally, film properties such as refractive index (n), stress, and extinction coefficient (k) can be tuned by varying the duty cycle of the pulsed RF plasma PECVD operations discussed herein.

[0019]

[0021] In another example, a film is deposited in a cyclic process in which a plasma, such as a silane plasma, is pulsed at a low deposition rate. The low deposition rate can be about 1 Angstrom / min to about 5 Angstroms / min. The film can be deposited in the presence of helium, hydrogen, or a combination of gases to a thickness of 20 Angstroms (Å), 10 Å, 5 Å, or about 3 Å to about 20 Å, for example, about 5 Å to about 10 Å. The film is then exposed to a hydrogen plasma for a predetermined time. The deposition and hydrogen plasma exposure are repeated for one or more iterations to form a film with a target in-film hydrogen content, or refractive index (n), stress, and / or extinction coefficient (k).

[0020]

[0022] 1 is a schematic diagram of a substrate processing system including a system 100 according to an embodiment of the present disclosure. The system 100 may be configured as a CVD system, including a plasma enhanced chemical vapor deposition (PECVD) system. The system 100 includes a processing chamber 102 having a substrate support 104 disposed within a processing space 146 formed within the processing chamber 102. The processing chamber 102 includes a chamber sidewall 122, a chamber bottom 124, and a chamber lid 140 that define the processing space 146. The chamber lid 140 includes a gas distribution assembly 116 to facilitate distribution of process gases and / or plasma.

[0021]

[0023] The system further includes a system controller 118 operable to control automated aspects of the process chamber 102. The system controller 118 facilitates control and automation of the entire process chamber 100 and may include a central processing unit (CPU), memory, and supporting circuits (or I / O). Software instructions and data may be coded and stored in the memory to instruct the CPU. The system controller 118 may communicate with one or more of the components of the process chamber 102, for example, via a system bus. Programs (or computer instructions) readable by the system controller 118 determine which tasks are executable on the substrate. In some implementations, the programs are software readable by the system controller 118, which may include code to control the pulsing of the plasma source, gas flows, movement sequences of various controlled components, and any combination thereof.

[0022]

[0024] Although shown as a single system controller 118, it is understood that multiple system controllers may be used in the embodiments described herein. For example, in one embodiment, a first controller controls the plasma source and a second controller controls the chamber automation.

[0023]

[0025] In some examples, the substrate support 104 is a substrate support pedestal. The substrate support 104 may include a mechanism for holding or supporting the substrate 106 on an upper surface of the substrate support 104. The substrate 106 may be a semiconductor substrate including silicon and / or germanium. In some examples, the substrate 106 may have one or more layers formed thereon, including a metal layer or a dielectric layer. Examples of holding mechanisms may include an electrostatic chuck, a vacuum chuck, a substrate holding clamp, and the like. The substrate support 104 may include a mechanism for controlling the substrate temperature (such as a heating device and / or a cooling device) and / or a mechanism for controlling the species flux and / or ion energy proximate to the substrate surface. The substrate support 104 includes one or more substrate support heating elements 108 disposed therein or otherwise thermally coupled to the substrate support 104. For example, one or more power sources 126 are coupled to one or more substrate support heating elements 108 to heat the substrate support 104 to a predetermined temperature while the substrate 106 is at a temperature between 300° C. and 500° C. (such as a temperature between 350° C. and 450° C.). In one embodiment, the one or more power sources 126 are configured to provide at least 5 kW of energy. Alternatively, the process chamber 102 may include one or more radiant heat lamps (not shown) positioned to irradiate the substrate 106 and / or the substrate support 104.

[0024]

[0026] The gas distribution assembly 116 is disposed in the processing chamber 102 opposite the substrate support 104. The gas distribution assembly 116 may be heated to a temperature of about 200° C. to about 350° C. before and / or during one or more operations in the processing chamber 102, such as a film deposition operation. The temperature of the gas distribution assembly 116 may be established before disposing the substrate 106 in the processing chamber 102. The temperature of the gas distribution assembly 116 may be maintained or modified within a predetermined temperature range while forming one or more films in the processing chamber 102. The elevated temperature of the gas distribution assembly 116 promotes gas flow into the processing chamber 102 in part by reducing the temperature difference between the gas distribution assembly 116 and the substrate support 104 on which the substrate 106 is disposed. In one example, the temperature of the gas distribution assembly 116 may be controlled by applying power from a power source 130 to a number of temperature control elements 110. In one example, the gas distribution assembly 116 can have multiple temperature control elements 110 disposed therein and configured to create temperature gradients and / or temperature zones across the gas distribution assembly 116. The multiple temperature control elements 110 can be used to raise, lower, or maintain the temperature of the gas distribution assembly 116. In some examples, the gas distribution assembly 116 can be coupled to an RF source (not shown) configured to provide power to the gas distribution assembly before, during, and / or after operation in the process chamber 102.

[0025]

[0027] The gas distribution assembly 116 further includes a plurality of apertures 132 formed through a face plate of the gas distribution assembly 116. Gases introduced into the processing chamber 102 from the gas manifold 114 are introduced into the processing space 146 through the plurality of apertures 132. The plurality of apertures 132 may be arranged in various configurations across the gas distribution assembly 116, including the chamber lid 140, as shown in FIG. 1. In various examples, the plurality of apertures 132 may be arranged as concentric rings, ring clusters, randomly arranged clusters, or other geometries. Although each aperture of the plurality of apertures 132 is illustrated herein as having approximately the same diameter, in other examples, it is contemplated that the diameter of the apertures 132 may vary. In some examples, the gas distribution assembly 116 includes zone heating such that the plurality of temperature control elements 110 may be controlled individually or in groups to create zones of different temperatures across the chamber lid 140.

[0026]

[0028] The gas distribution assembly 116 may be disposed near the optional chamber liner 120 such that the optional chamber liner 120 is flush with the gas distribution assembly 116 (either in direct contact or flush with an adhesive disposed therebetween). In embodiments in which the optional chamber liner 120 is used, the liner sidewall 138 is exposed to the processing space 146 and the optional chamber liner therefore protects the chamber sidewall 122. In some implementations, the optional chamber liner 120 may further be disposed along a chamber bottom 124 (e.g., a bottom surface) of the processing chamber 102. Thus, the chamber sidewall 122 of the processing chamber 102 may be protected from the processing space 146 by the optional chamber liner 120. One or more exhaust systems (not shown) may be coupled to the processing chamber 102 and used to remove excess process gases or by-products from the processing space 146 during or after processing.

[0027]

[0029] In one example, the gas distribution assembly 116 may further be coupled to a cooler plate 148. In one example, when the cooler plate 148 is coupled to the gas distribution assembly 116, the cooler plate 148 facilitates control over the temperature or temperature gradient across the gas distribution assembly 116. In some implementations, the cooler plate 148 includes a number of channels (not shown) formed therein. The multiple channels allow a temperature control fluid supplied by a temperature control fluid supply (chiller) 150 to flow through the cooler plate 148 and facilitate control over the temperature of the gas distribution assembly 116.

[0028]

[0030] As discussed herein, a film deposition operation may include forming one or more films on a substrate 106 disposed on a substrate support 104, as well as forming one or more films on exposed surfaces of the processing chamber 102. In one example, the one or more films formed inside the processing space 146 may be formed on the chamber sidewall 122 (e.g., when the optional chamber liner 120 is excluded). When the optional chamber liner 120 is used in the processing chamber 102, the one or more films formed as discussed herein may be formed on the liner sidewall 138 instead of the chamber sidewall 122, since the chamber sidewall 122 is protected from the processing space 146 by the optional chamber liner 120.

[0029]

[0031] The one or more gas sources 112 are coupled to the process chamber 102 via a gas manifold 114. The gas manifold 114 is coupled to a gas distribution assembly 116 and configured to deliver one or more gases from the one or more gas sources 112 to the process space 146. Each of the one or more gas sources 112 may include a carrier gas, an ionizable gas for plasma formation (such as hydrogen or He), or a precursor for film formation. The RF power source 136 may be electrically connected to a chamber wall electrode 142 in the chamber sidewall 122. The RF power source 136 may be a 13.56 MHz RF power source. The RF power source 136 may further be electrically connected to a substrate support electrode 152 disposed in the substrate support 104. A plasma may be generated in the process space 146 via the RF power source 136. The RF power supply 136 is a modulated power supply configured to generate an RF field using a chamber wall electrode 142 (which may be a positive electrode) and a substrate support electrode 152 (which may be a ground electrode). The RF power supply 136 may be pulsed during various operations. In some examples, a remote plasma source 134 may be used and coupled to the gas distribution assembly 116 to deliver plasma to the processing chamber 102.

[0030]

[0032] FIG. 2 is a flow chart of a method 200 for forming a film using a pulsed RF plasma. The method 200 may be used to form one or more films on a substrate disposed on a substrate support in a processing chamber 102, such as the processing chamber 102 shown in FIG. 1. In this example of the method 200, in step 202, a substrate, such as the substrate 106 in FIG. 1, is disposed on a substrate support, such as the substrate support 104. In another example, the method 200 may be used to form one or more films inside the processing chamber 102 on the substrate, including the chamber sidewalls 122, the chamber bottom 124, the chamber lid 140, and other exposed surfaces (e.g., to season one or more surfaces within the processing chamber 102). As discussed in FIG. 1, when an optional chamber liner 120 is used, one or more films may be formed on the optional chamber liner 120. In one example, the method 200 is performed without a substrate being disposed in the processing chamber 102. In another example, the method 200 is used to form one or more films on both a substrate 106 disposed within the processing chamber 102 and on one or more exposed surfaces of the processing chamber 102.

[0031]

[0033] In step 204, one or more film precursor gases are introduced into the process chamber 102. The one or more film precursor gases may include silane (SiH4), Si2H6, or other hydride or silicon-based precursors. In another example, the one or more film precursor gases may include a carbon-hydrogen-containing compound. For example, the one or more film precursor gases may include C2H2 or C3H6. In another example, the one or more film precursor gases may include germanium, such as GeH4. In another example, the one or more film precursor gases may include arsenic (As), such as AsH3. In one example, the one or more film precursor gases are introduced in step 204 at a flow rate of about 100 sccm to about 1000 sccm. In one example, the one or more film precursor gases are introduced in step 204 at a flow rate of about 300 sccm to about 800 sccm.

[0032]

[0034] Further, in step 204, one or more process gases may be introduced into the processing chamber 102. The one or more film precursor gases and the process gas may be introduced in step 204 via the gas distribution assembly 116 of FIG. 1. The one or more process gases may include argon (Ar), hydrogen, and / or helium (He). In one example, helium and argon are introduced into the processing chamber 102 in step 204 along with the at least one film precursor gas. In another example, helium, hydrogen, and argon are introduced into the processing chamber 102 in step 204. In another example, hydrogen and argon are introduced into the processing chamber 102 in step 204. Helium may be introduced into the processing chamber 102 in step 204 at a flow rate of about 6500 sccm to about 8000 sccm. Argon may be introduced into the processing chamber 102 in step 204 at a flow rate of about 100 sccm to about 10,000 sccm. In one example, hydrogen may be introduced into the processing chamber 102 in step 204 at a flow rate of about 100 sccm to about 1,000 sccm. In another example, hydrogen may be introduced into the processing chamber 102 in step 204 at a flow rate of about 6,500 sccm to about 8,000 sccm. In one example, the ratio of the flow rate of helium to the flow rate of hydrogen is about 4:1 to about 9:1. In another example, the ratio of the flow rate of helium to the flow rate of hydrogen is about 5:1 to about 8:1. In some examples, there may be a target flow ratio between the one or more film precursor gases introduced in step 204 and the one or more process gases introduced in step 204. In one example, the ratio of the flow rate of at least one film precursor gas (FPC) to the flow rate of the process gas (FG) (FPC:FG) is greater than 1:10.

[0033]

[0035] In another example, hydrogen, argon, and helium are introduced into the processing chamber 102 in step 204. Hydrogen may be introduced into the processing chamber 102 in step 204 at a flow rate of about 6,500 sccm to about 8,000 sccm. Argon may be introduced into the processing chamber 102 in step 204 at a flow rate of about 100 sccm to about 10,000 sccm. Helium may be introduced into the processing chamber 102 in step 204 at a flow rate of about 100 sccm to about 1000 sccm. In one example, the ratio of the flow rate of hydrogen to the flow rate of helium is about 4:1 to about 9:1. In another example, the ratio of the flow rate of hydrogen to the flow rate of helium is about 5:1 to about 8:1.

[0034]

[0036] In yet another example, hydrogen and argon are introduced into the processing chamber 102 in step 204. Hydrogen may be introduced into the processing chamber 102 in step 204 at a flow rate between about 6,500 sccm and about 8,000 sccm. Argon may be introduced into the processing chamber 102 in step 204 at a flow rate between about 100 sccm and about 10,000 sccm. In one example, the ratio of the flow rate of hydrogen to the flow rate of helium is between about 4:1 and about 9:1. In another example, the ratio of the flow rate of hydrogen to the flow rate of helium is between about 5:1 and about 8:1.

[0035]

[0037] In step 206, the precursor gas(es) and process gas(es) are ionized to form a plasma. In step 208, an RF power source, such as 136 in FIG. 1, is pulsed while the process gas(es) and precursor gas(es) are introduced into the processing chamber. Each pulse in step 208 has a total time T for the duty cycle. TOT T TOT is T ON and T OFF In one example, T in step 208 ON is T TOT In another example, the T ON is T TOT Less than 20% of, e.g., T TOTIn another example, the T ON is T TOT Less than 10% of, e.g., T TOT In a further example, the T ON is T TOT Less than 5% of, e.g., T TOT It is about 1% to about 4% of the total.

[0036]

[0038] Further, in the method 200, the pressure in the processing chamber 102 during at least steps 204, 206, and 208 can be from about 1 mTorr to about 50 Torr. In another example, the pressure in the processing chamber 102 during at least steps 204, 206, and 208 can be from about 8 Torr to about 50 Torr, such as from about 8 Torr to about 20 Torr. Further, in the method 200, the temperature in the processing chamber 102 during at least steps 204, 206, and 208 can be from about 300° C. to about 500° C. In another example, the temperature in the processing chamber 102 during steps 204, 206, and 208 can be from about 350° C. to about 450° C. The power density of a PECVD operation is the amount of power applied to the processing chamber per unit volume of the processing chamber. The peak power density is the highest value of the power density during the processing chamber operation. In one example, the peak power density during film deposition is 0.03 W / cm 2 to about 1.64 W / cm 2 In another example, the peak power density during film deposition can be about 0.06 W / cm 2 or about 0.12 W / cm 2 In another example, the power density during method 200 is about 0.03 W / cm 2 to about 1.64 W / cm 2 In some examples, the power density during method 200 can be about 0.06 W / cm 2 to about 0.3 W / cm 2 It is.

[0037]

[0039] In step 210 of method 200, a film is formed. The film formed in step 210 may be formed on the substrate 106 when step 202 is performed. In another example, the film formed in step 210 may be formed on the lid, bottom, sidewalls, or other exposed surface of the processing chamber 102. Pulsing the plasma in step 208 using RF power reduces the hydrogen concentration of the plasma in the processing space 146 and increases the rate of hydrogen desorption from the surface of the substrate 106 or exposed surfaces of the processing chamber 102. The reduced desorption reduces the hydrogen content of the film formed in step 210. Formation of the film from the film precursor in step 210 is achieved by reducing the T of step 208. ON It will be done according to the period.

[0038]

[0040] The film formed in step 210 can be formed to have a thickness of up to about 500 Å. The film formed in step 210 can include a hydrogen content of less than about 10%. In another example, the film formed in step 210 can include a hydrogen content of less than about 5%. In another example, the film formed in step 210 can include a hydrogen content of less than about 3%. In another example, the film formed in step 210 can include a hydrogen content of less than about 2%. In another example, the film formed in step 210 can include a hydrogen content of less than about 1%. Depending on the precursor gas introduction and pulsing of the plasma, the film formed in step 210 can be deposited at a rate of about 10 Å / min to about 1,000 Å / min. In another example, the deposition rate can be about 80 Å / min to about 300 Å / min. The film formed using method 200 can be an amorphous film, such as a-Si, or a polycrystalline film. The film formed using method 200 may have a refractive index of about 4.25 to about 4.45 at 633 nm. In another example, which may be combined with other examples herein, the film formed using method 200 exhibits an extinction coefficient (k) of about 0.140 to about 0.180. In another example, which may be combined with other examples herein, the film formed using method 200 has a k of about 0.140 to about 0.160. In another example, which may be combined with other examples herein, the film formed using method 200 exhibits an intra-film stress of about -1100 MPa to about -300 MPa. Furthermore, in an example of method 200 that may be combined with other examples herein, the variation in film thickness, which may be referred to as film uniformity, may be less than about 1% to about 6%. In another example, which may be combined with other examples herein, the film uniformity is less than about 4%.

[0039]

[0041] FIG. 3 is a flow chart of a method 300 for forming a film using a pulsed RF plasma. The method 300 is similar to the method 200, but the method 300 forms a film in a cyclic process. The method 300 can be used to form one or more films on a substrate disposed on a substrate support in a processing chamber, such as the processing chamber 102 shown in FIG. 1. In this example of the method 300, in step 302, a substrate, such as the substrate 106 in FIG. 1, is disposed on a substrate support, for example the substrate support 104 in FIG. 1. In another example, the method 300 can be used to form one or more films on an inner surface of the processing chamber 102, such as a seasoning process. During the seasoning process, the method 300 is performed without a substrate disposed in the processing chamber 102. In another example, the method 300 can be used to form one or more films on both the substrate 106 disposed in the processing chamber 102 and on the inner surface of the processing chamber 102.

[0040]

[0042] In step 304, one or more film precursor gases are introduced into the process chamber. The one or more film precursor gases may include silane (SiH4), Si2H6, or other carbon or silicon-containing precursors. In another example, the one or more film precursor gases may include C2H2 or C3H6. In another example, the one or more film precursor gases may include germanium, such as GeH4. In another example, the one or more film precursor gases may include arsenic (As), such as AsH3. In one example, the one or more film precursor gases are introduced in step 304 at a flow rate of about 100 sccm to about 1000 sccm.

[0041]

[0043] Further, in step 304, one or more process gases may be introduced into the processing chamber 102. The one or more film precursor gases and the process gas may be introduced in step 304 via the gas distribution assembly 116 of FIG. 1. The one or more process gases may include argon (Ar), hydrogen, and / or helium (He). In one example, helium and argon are introduced into the processing chamber in step 304 along with at least one film precursor gas. In another example, helium, hydrogen, and argon are all introduced into the processing chamber in step 304. In another example, hydrogen and argon are introduced into the processing chamber in step 304. Helium may be introduced into the processing chamber in step 304 at a flow rate of about 6,500 sccm to about 8,000 sccm. Argon may be introduced into the processing chamber in step 304 at a flow rate of about 100 sccm to about 10,000 sccm. Hydrogen may be introduced into the process chamber in step 304 at a flow rate of about 100 sccm to about 1,000 sccm. In another example, hydrogen may be introduced into the process chamber in step 304 at a flow rate of about 6,500 sccm to about 8,000 sccm. In one example, the ratio of the flow rate of helium to the flow rate of hydrogen is about 4:1 to about 9:1. In another example, the ratio of the flow rate of helium to the flow rate of hydrogen is about 5:1 to about 8:1. In some examples, there may be a target flow ratio between the one or more film precursor gases introduced in step 304 and the one or more process gases introduced in step 304. In one example, the ratio of the flow rate of at least one film precursor gas (FPC) to the flow rate of a process gas (FG) (FPC:FG) is greater than 1:10.

[0042]

[0044] In another example, hydrogen, argon, and helium are introduced into the processing chamber 102 in step 304. Hydrogen may be introduced into the processing chamber 102 in step 304 at a flow rate of about 6,500 sccm to about 8,000 sccm. Argon may be introduced into the processing chamber 102 in step 304 at a flow rate of about 100 sccm to about 10,000 sccm. Helium may be introduced into the processing chamber 102 in step 304 at a flow rate of about 100 sccm to about 1000 sccm. In one example, the ratio of the flow rate of hydrogen to the flow rate of helium is about 4:1 to about 9:1. In another example, the ratio of the flow rate of hydrogen to the flow rate of helium is about 5:1 to about 8:1.

[0043]

[0045] In yet another example, hydrogen and argon are introduced into the processing chamber 102 in step 304. Hydrogen may be introduced into the processing chamber 102 at a flow rate between about 6,500 sccm and about 8,000 sccm. Argon may be introduced into the processing chamber 102 at a flow rate between about 100 sccm and about 10,000 sccm in step 304. In one example, the ratio of the flow rate of hydrogen to the flow rate of helium is between about 4:1 and about 9:1. In another example, the ratio of the flow rate of hydrogen to the flow rate of helium is between about 5:1 and about 8:1.

[0044]

[0046] In step 306, one or more film precursor gases are ionized into a plasma. In step 308, an RF power source, such as 136 in FIG. 1, is pulsed to deposit a first film interlayer, e.g., a sub-portion of the film. The first film interlayer can be deposited on the substrate 106 in step 308. In another example, the first film interlayer can be deposited on one or more interior surfaces of the processing chamber 102 in step 308. During step 308, a process gas including argon (Ar) and helium (He) can be present in the processing chamber and ionized into a plasma. In one example, no hydrogen is present in the processing chamber 102 during step 308. In another example, a hydrogen plasma is present in the processing chamber 102 during step 308.

[0045]

[0047] The first film interlayer formed in step 308 may be deposited at a rate of about 1 Å / min to about 10 Å / min, for example, about 2 Å / min to about 5 Å / min. Pulsing the plasma in step 308 using RF power reduces the hydrogen plasma concentration in the process space and increases the rate of hydrogen desorption from the surface, reducing the hydrogen content of each film interlayer to within a predetermined range or below a predetermined maximum. As discussed above, each pulse of RF power in step 308 reduces the hydrogen plasma concentration in the process space and increases the rate of hydrogen desorption from the surface, reducing the hydrogen content of each film interlayer to within a predetermined range or below a predetermined maximum. ON and T OFF The total time for the duty cycle T is the sum of TOT In one example, T in step 308 ON is T TOT In one example, the T ON is T TOT Less than 20% of, e.g., T TOT In one example, the T ON is T TOT Less than 10% of, e.g., T TOT In yet another example, the T ON is T TOT Less than 5% of, e.g., T TOT The deposition of the membrane intermediate layer from the membrane precursor is performed in step 308 at T ON It will be held during the period.

[0046]

[0048] Further, in the method 300, the pressure in the processing chamber 102 during one or more of steps 304, 306, and 308 can be from about 1 mTorr to about 50 Torr. In another example, the pressure in the processing chamber 102 during one or more of steps 304, 306, and 308 can be from about 8 Torr to about 50 Torr, such as from about 8 Torr to about 20 Torr. Further, in the method 300, the temperature in the processing chamber 102 during one or more of steps 304, 306, and 308 can be from about 300° C. to about 500° C. In another example, the temperature in the processing chamber 102 during one or more of steps 304, 306, and 308 can be from about 300° C. to about 500° C. In yet another example, the temperature in the processing chamber 102 during one or more of steps 304, 306, and 308 can be from about 350° C. to about 450° C. The power density during the method 300 can be about 0.03 W / cm 2 to about 1.64 W / cm 2 In some examples, the power density during method 300 can be about 0.06 W / cm 2 to about 0.3 W / cm 2 It is.

[0047]

[0049] In step 310, the process chamber 102 is optionally purged to remove the precursor plasma. In some examples, no purging is performed. In other examples, the carrier and / or purge gas is continuously flowed such that the plasma remains ignited in the chamber and the precursor gas flow is stopped and removed from the chamber. In examples where no purging is performed, the hydrogen plasma may be present at least between steps 306 and 308. Further in this example, the method 300 may proceed from step 308 to step 312. In step 312, a hydrogen plasma is formed and / or maintained in the process chamber 102 and the first film interlayer formed in step 308 is exposed to the hydrogen plasma.

[0048]

[0050] In step 314 of the method 300, a film is formed from one or more intermediate layers deposited in one or more repetitions of steps 304, 306, 308, 310, and 312. The total thickness of the intermediate layers formed through these repetitions can be up to about 50 Å. Each intermediate layer formed through each cycle can have a thickness of about 2 Å to about 49 Å. The film formed in step 314 through one or more repetitions of steps 304, 306, 308, 310, and 312 can include a hydrogen content of less than about 10%, for example, less than about 5%, or less than about 3%, or less than about 2%, for example, less than about 1%. The film formed in step 314 can be formed on an interior surface of a processing chamber. In another example, which can be combined with other examples, the film can be formed on a substrate 106 disposed in a processing chamber 102. In one example, the film formed in step 314 can have a fine crystalline grain structure.

[0049]

[0051] Thus, using the systems and methods discussed herein, a pulsed RF plasma is used alone or in combination with H plasma exposure to deposit films. The films deposited herein may be formed on substrates and / or chamber components or other exposed surfaces. The pulsed RF plasma may include one or more semiconductor film precursors, and the plasma may be pulsed using RF power and may have multiple pulses with a duty cycle on time of less than about 20%.

[0050]

[0052] Embodiments may include one or more of the following advantages: Films formed according to the methods discussed herein may have a hydrogen content of less than 10%. The systems and methods discussed herein may form films that include predetermined film properties, such as extinction coefficient, film stress, and refractive index.

[0051]

[0053] All of the embodiments and functional operations described herein may be implemented in digital electronic circuitry, or computer software, firmware, or hardware, or in combinations of these, including the structural means disclosed herein and their structural equivalents. The embodiments described herein may be implemented as one or more non-transitory computer program products, i.e., one or more computer programs tangibly embodied in a machine-readable storage device for execution by or to control the operation of a data processing apparatus (e.g., a programmable processor, a computer, or multiple processors or computers).

[0052]

[0054] The processes and logic flows described herein may be implemented by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows may also be executed by, and an apparatus may be implemented as, an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit), for example.

[0053]

[0055] The term "data processing apparatus" encompasses all apparatus, devices, and machines for processing data, including, by way of example, a programmable processor, a computer, or multiple processors or computers. An apparatus may include, in addition to hardware, code that forms an execution environment for the computer program in question, such as code constituting a processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of these. Processors suitable for the execution of computer programs may include, by way of example, both general purpose and special purpose microprocessors, as well as any one or more processors of any kind of digital computer.

[0054]

[0056] Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media and memory devices, including, by way of example, semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices), magnetic disks (e.g., internal hard disks or removable disks), magneto-optical disks, and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by, or incorporated in, special purpose logic circuitry.

[0055]

[0057] While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope of the disclosure, the scope of which is determined by the following claims.

Claims

1. 1. A method of forming a membrane, comprising: ionizing a precursor gas comprising C 3 H 6 , C 2 H 2 , or GeH 4 to form a plasma in a process space of a process chamber; pulsing an RF power source coupled to the processing chamber; in response to pulsing, depositing a film on a substrate disposed on a substrate support inside the processing space while the RF power is pulsing. wherein the substrate support is at a temperature of 350° C. to 450° C., and the film contains less than 5% hydrogen content and has a thickness variation of less than 6%.

2. 10. The method of claim 1 , wherein introducing the precursor gas comprises introducing the precursor gas through a gas distribution assembly on an opposite side of the substrate support, the gas distribution assembly being at a temperature of 200° C. to 350° C. during deposition of the film.

3. 10. The method of claim 1, further comprising depositing the film at a deposition rate of 1 Å / sec to 8 Å / sec while pulsing the RF power source.

4. Pulsing the RF power source comprises providing a duty cycle on time (T ＯＮ 2. The method of claim 1 , comprising:

5. The method of claim 1 , wherein the precursor gas comprises silicon (Si) or germanium (Ge).

6. The method of claim 1 , wherein the precursor gas comprises hydrogen.

7. 1. A method of forming a membrane, comprising: introducing a precursor gas comprising C 3 H 6 , C 2 H 2 , or GeH 4 into a process volume of a process chamber having a chamber lid, a chamber bottom, and a sidewall extending therebetween; ionizing the precursor gas to form a plasma; The duty cycle on time (T ＯＮ ) to the total cycle time (T ＴＯＴ pulsing said RF power source to achieve a power dissipation of less than 20% of depositing a film having a hydrogen content of less than 5% on a substrate disposed on a substrate support inside the processing space; wherein the substrate support is at a temperature of 350° C. to 450° C. and the film thickness has a variation of less than 6%.

8. The duty cycle on time (T ＯＮ ) is the total cycle time (T ＴＯＴ 8. The method of claim 7, wherein the concentration of the ionic liquid is less than 10% of the concentration of the ionic liquid.

9. The method of claim 7 , wherein the film comprises less than 5% hydrogen content.

10. The method of claim 7 , wherein the membrane has a thickness variation of less than 6%.

11. The method of claim 7 , wherein the film is deposited on a substrate disposed on a substrate support in the processing chamber.

12. The method of claim 7 , wherein the film is deposited on at least one of the chamber lid, the chamber bottom, and the sidewalls of the processing chamber.

13. The method of claim 7 , wherein the depositing of the film is performed at a deposition rate of 1 Å / min to 10 Å / min.

14. 1. A method of forming a membrane, comprising: (a) forming a plasma in a process chamber from a precursor gas comprising C3H6, C2H2, or GeH4; (b) The RF power source is pulsed to reduce the duty cycle on time (T ＯＮ ) to the total cycle time (T ＴＯＴ ) to be less than 20% of the total (c) depositing a first film interlayer on a substrate disposed on a substrate support inside the processing chamber, the substrate support being at a temperature between 350° C. and 450° C.; (d) subsequent to (c), purging the processing chamber; (e) subsequent to (d), introducing a hydrogen plasma into the processing chamber; (f) repeating (b) through (e) to form a film having a hydrogen content of less than 5% and a thickness variation of less than 6%. The method includes:

15. 15. The method of claim 14, wherein the substrate comprises at least one of a lid surface of the processing chamber, a bottom surface of the processing chamber, a sidewall of the processing chamber, and a substrate disposed on a substrate support within the processing chamber.

16. 15. The method of claim 14, wherein the film deposition rate in (c) is from 1 Å / min to 5 Å / min.

17. The method of claim 14 , wherein the first film interlayer has a thickness of from 2 Å to 50 Å.

18. The method of claim 14, wherein the film has a thickness of 100 Å to 500 Å.

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