Method of filling trenches on substrate surface

Abstract

A method of filling a trench on a surface of a substrate is provided. The method may include positioning a substrate on a substrate support disposed within a reaction chamber, where a pressure of the reaction chamber is less than 200 Pa; continuously flowing a carbon precursor into the reaction chamber; continuously flowing etching gas into the reaction chamber; generating a plasma in the reaction chamber by applying a first radio frequency (RF) power to one of the one or more electrodes of the reaction chamber; and depositing an amorphous carbon layer in the trench on the substrate.

Description

Technical Field

[0001] The present disclosure generally relates to methods of forming structures suitable for use in manufacturing electronic devices. More specifically, examples of the present disclosure relate to methods of forming structures that include depositing a layer of material that can fill trenches on a surface of the structure. Background Art

[0002] In the fabrication of devices such as semiconductor devices, it is often desirable to fill trenches on a substrate surface. Some techniques for filling trenches include depositing a layer of flowable material, such as a flowable carbon material.

[0003] Although using a flowable carbon material to fill the trenches may work well for some applications, deposition techniques for flowable carbon may have a low elastic modulus and require a curing step. Therefore, there is a need for an improved method of filling trenches on a substrate surface with a material having a high elastic modulus without requiring a curing step.

[0004] Any discussion set forth in this section, including discussion of problems and solutions, has been included in the present disclosure merely to provide a context for the present disclosure and should not be considered as an admission that any or all of the discussion was known or constituted prior art at the time the present invention was made. Summary of the invention

[0005] This summary is provided to introduce some concepts in a simplified form. These concepts are further described in detail in the detailed description of the example embodiments disclosed below. This summary is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0006] According to an exemplary embodiment of the present disclosure, a method for filling a groove on a substrate is provided. The method may include the following steps: positioning a substrate on a substrate support, the substrate support being disposed in a reaction chamber, wherein a pressure in the reaction chamber is less than 200 Pa; continuously flowing a carbon precursor into the reaction chamber; continuously flowing an etching gas into the reaction chamber; generating plasma in the reaction chamber by applying a first radio frequency (RF) power to one of the one or more electrodes of the reaction chamber; and depositing an amorphous carbon layer in the groove on the substrate.

[0007] In various embodiments, the substrate support may be maintained at a temperature between about 350°C and about 550°C.

[0008] In various embodiments, the first RF power may be applied continuously.

[0009] In various embodiments, the first RF power may be less than 2000W.

[0010] In various embodiments, the frequency of the first RF may be between 10 and 30 MHz.

[0011] In various embodiments, the second RF power may be applied to one of the one or more electrodes of the reaction chamber.

[0012] In various embodiments, the second RF power may be less than 500W.

[0013] In various embodiments, the frequency of the second RF may be between 100 KHz and 1000 KHz.

[0014] In various embodiments, the flow rate of the carbon precursor may be between 10 and 200 seem.

[0015] In various embodiments, the carbon precursor may include one of: CH4, C2H2, C3H8, C4H10, C2H4, C3H6, C4H8, C5H10, C9H12, C6H11N3, C10H12O2, or a combination thereof.

[0016] In various embodiments, the etching gas may include one of: H2, He, O2, CO2, NH3, N2O, or a combination thereof.

[0017] In various embodiments, the flow rate of the etching gas may be between 5 and 200 seem.

[0018] In various embodiments, one of the electrodes may be part of the substrate support.

[0019] In various embodiments, the elastic modulus of the amorphous carbon layer may be greater than 20 GPa. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] A more complete understanding of exemplary embodiments of the present disclosure may be obtained by referring to the detailed description and claims when considered in conjunction with the following illustrative drawings.

[0021] Figure 1 A method according to an exemplary embodiment of the present disclosure is shown.

[0022] Figure 2 The structure formed in the prior art reference is shown.

[0023] Figure 3 A schematic diagram showing a structure according to an exemplary embodiment of the present disclosure.

[0024] Figure 4 A plasma system according to an exemplary embodiment of the present disclosure is shown.

[0025] It should be understood that the elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the size of some elements in the drawings may be exaggerated relative to other elements to help understand the illustrated embodiments of the present disclosure. DETAILED DESCRIPTION

[0026] Although certain embodiments and examples are disclosed below, those skilled in the art will appreciate that the invention extends beyond the specifically disclosed embodiments and / or uses of the invention and their obvious modifications and equivalents. Therefore, it is intended that the scope of the disclosed invention should not be limited by the specifically disclosed embodiments described below.

[0027] As used herein, the term "substrate" may refer to any one or more underlying materials, including any one or more underlying materials that may be modified or on which a device, circuit, or film may be formed. A "substrate" may be continuous or non-continuous; rigid or flexible; solid or porous; and combinations thereof. A substrate may be in any form, such as a powder, a plate, or a workpiece. A plate-like substrate may include wafers of various shapes and sizes. A substrate may be made of semiconductor materials, including, for example, silicon, silicon germanium, silicon oxide, gallium arsenide, gallium nitride, and silicon carbide.

[0028] For example, a substrate in powder form may have applications in pharmaceutical manufacturing. A porous substrate may comprise a polymer. Examples of workpieces may include medical devices (e.g., stents and syringes), jewelry, tooling equipment, components for battery manufacturing (e.g., anodes, cathodes, or separators), or components for photovoltaic cells, etc.

[0029] The continuous substrate may extend beyond the boundaries of the processing chamber in which the deposition process occurs. In some processes, the continuous substrate may be moved through the processing chamber so that the process continues until the end of the substrate is reached. The continuous substrate may be provided from a continuous substrate feed system to allow the continuous substrate to be manufactured and output in any suitable form.

[0030] Non-limiting examples of continuous substrates may include sheets, nonwoven films, rolls, foils, meshes, flexible materials, bundles of continuous filaments or fibers (eg, ceramic fibers or polymer fibers). A continuous substrate may also include a carrier or sheet on which a discontinuous substrate is mounted.

[0031] The illustrations presented herein are not meant to be actual views of any particular material, structure, or device but are merely idealized representations used to describe embodiments of the present disclosure.

[0032] The specific embodiments shown and described are illustrations of the present invention and its best mode and are not intended to limit the scope of these aspects and embodiments in any way. In fact, for the sake of brevity, the traditional manufacturing, connection, preparation and other functional aspects of the system may not be described in detail. In addition, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and / or physical connections between various elements. Many alternative or additional functional relationships or physical connections may exist in actual systems, and / or may not exist in some embodiments.

[0033] It should be understood that the configuration and / or method described herein are exemplary in nature, and these specific embodiments or examples should not be considered restrictive, because many variations are possible. The specific routine or method described herein can represent one or more of any number of processing strategies. Therefore, the various actions shown can be performed in the order shown, in other orders, or omitted in some cases.

[0034] The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various processes, systems and configurations, and other features, functions, acts and / or properties disclosed herein, and any and all equivalents thereof.

[0035] In the present disclosure, "gas" may include materials that are gaseous at normal temperature and pressure, evaporated solids, and / or evaporated liquids, and may be composed of a single gas or a gas mixture depending on the situation. Gas introduced without passing through a gas supply unit (e.g., a shower plate, etc.) may be used, for example, to seal a reaction space, and may include sealing gases such as rare gases or other inert gases. The terms inert gas, carrier gas, and diluent gas refer to gases that do not participate in chemical reactions to an appreciable degree and / or gases that are capable of exciting precursors when plasma power is applied.

[0036] As used herein, the terms "film" and "thin film" may refer to any continuous or discontinuous structure and material deposited by the methods disclosed herein. For example, "film" and "thin film" may include 2D materials, nanorods, nanotubes or nanoparticles, or even partial or complete molecular layers or partial or complete atomic layers or clusters of atoms and / or molecules. "Film" and "thin film" may include materials or layers with pinholes, but still at least partially continuous.

[0037] Figure 1A method 100 for filling a trench on a surface of a substrate according to an exemplary embodiment of the present disclosure is shown. The method 100 may include the following steps: positioning a substrate on a substrate support, the substrate support being disposed in a reaction chamber (step 101); wherein the pressure of the reaction chamber is less than 200 Pa; continuously flowing a carbon precursor into the reaction chamber (step 103); continuously flowing an etching gas into the reaction chamber (step 104); generating a plasma in the reaction chamber by applying a first radio frequency (RF) power to one of the one or more electrodes of the reaction chamber (107); and depositing an amorphous carbon layer in the trench on the substrate (step 109).

[0038] During step 101 of providing a substrate on a substrate support within a reaction chamber, the substrate may be provided into a reaction chamber of a gas phase reactor. According to examples of the present disclosure, the reaction chamber may form part of a deposition reactor, such as a plasma enhanced chemical vapor deposition (PECVD) reactor. The various steps of the methods described herein may be performed in a single reaction chamber (e.g., sequentially), or may be performed in multiple reaction chambers, such as reaction chambers on a cluster tool.

[0039] During step 101, the substrate may be brought to a desired temperature and / or the reaction chamber may be brought to a desired pressure, such as a temperature and / or pressure suitable for subsequent steps. For example, the temperature within the reaction chamber (e.g., the temperature of the substrate or substrate support) may be between about 350° C. and about 550° C. The pressure within the reaction chamber may be maintained at less than 200 Pa. According to a specific example of the present disclosure, the substrate includes one or more features, such as narrow grooves and wide grooves.

[0040] During step 103, a carbon precursor may be flowed onto the substrate surface. A carbon precursor that fills the trench may be flowed during step 103. The flow rate of the carbon precursor is between 10 and 200 sccm. The carbon precursor may include one of: CH4, C2H2, C3H8, C4H10, C2H4, C3H6, C4H8, C5H10, C9H12, C6H11N3, C10H12O2, or a combination thereof. During step 103, one or more inert gases, carrier gases, and diluent gases may be provided to the reaction chamber, such as argon, helium, nitrogen, or any mixture thereof.

[0041] During step 104, the etching gas may be continuously supplied to the reaction chamber. Steps 104 and 103 may overlap. The ratio of etching to deposition may be substantially equal. The etching gas may include one of: H2, He, O2, CO2, NH3, N2O, or a combination thereof. The flow rate of etching may range from about 5 to about 200 sccm.

[0042] During step 107, a plasma may be generated in the reaction chamber by applying a first radio frequency (RF) power to one of the one or more electrodes of the reaction chamber. The plasma power range for deposition may be from about 10 W to about 2000 W. The RF frequency range of the plasma power may be from 400 kHz to 100 MHz. In some embodiments, the frequency may be between 10 MHz and 30 MHz. In some embodiments, a second RF power may be applied to one of the one or more electrodes of the reaction chamber. The frequency of the second RF may be between 100 KHz and 1000 KHz, and the second RF power may be less than 500 W.

[0043] Figure 2 2. The structure formed in the prior art reference is shown. The structure 202 may include a substrate 206 and protrusions 210, 221 formed thereon. The structure 202 includes a deposited material 218 covering the substrate 206. As shown, the deposited material 218 from the deposition step 101 includes a void 215 formed in a groove 222 between the protrusions 210 and 221. After the material 218 is deposited (e.g., enough material to fill the groove 222), the deposited material 218 may be exposed to a curing (post-processing) step to cause the deposited material 218 to flow within the groove 222, thereby forming a structure 204 including a processed material 224.

[0044] Figure 3 A schematic diagram of a structure according to an exemplary embodiment of the present disclosure is shown. The carbon precursor and etching gas can be supplied to the reaction chamber simultaneously. By performing deposition and etching simultaneously, amorphous carbon can be filled from bottom to top. The elastic modulus of the amorphous carbon layer can be greater than 20 GPa.

[0045] Figure 4 A plasma reactor system 500 is shown according to an exemplary embodiment of the present disclosure. The plasma reactor system 500 can be used to perform one or more steps or sub-steps described herein, and / or form one or more structures described herein, or portions thereof.

[0046] The plasma reactor system 500 may include a pair of conductive flat plate top and bottom electrodes 4, 2 parallel and facing each other in the interior 11 (reaction zone) of the reaction chamber 3. Plasma may be ignited in the reaction chamber 3 by applying RF power (e.g., 13.56 MHz, 27 MHz, or 60 MHz) and / or low frequency power, for example, from a power source 25 to one electrode (e.g., the top electrode 4) and electrically grounding the other electrode (e.g., the bottom electrode 2). A temperature regulator may be provided in the bottom electrode 2 (serving as a substrate support 2), and the temperature of the substrate 1 placed thereon may be maintained at a desired temperature. The top electrode 4 may serve as a gas distribution device, such as a shower plate. Reactant gas, carrier gas, inert gas, dilution gas (if any), precursor gas, etc. may be introduced into the reaction chamber 3 through the shower plate 4 using one or more of gas lines 20, gas lines 21, and gas lines 22, respectively. Although three gas lines are shown, the reactor system 500 may include any suitable number of gas lines.

[0047] In the reaction chamber 3, a circular duct 13 with an exhaust line 7 may be provided, through which the gas in the interior 11 of the reaction chamber 3 can be exhausted. In addition, the transfer chamber 5 arranged below the reaction chamber 3 may be provided with a sealing gas line 24 to introduce the sealing gas into the interior 11 of the reaction chamber 3 via the interior 16 (transfer zone) of the transfer chamber 5, wherein a partition plate 14 for separating the reaction zone and the transfer zone may be provided (a gate valve through which the wafer is transferred into or out of the transfer chamber 5 is omitted in this figure). The transfer chamber may also be provided with an exhaust line 6.

[0048] Those skilled in the art will appreciate that the apparatus includes one or more controllers that are programmed or otherwise configured to cause one or more of the method steps described herein to be performed. The controller is in communication with various power sources, heating systems, pumps, robots, and gas flow controllers or valves of the reactor, as those skilled in the art will appreciate.

[0049] In some embodiments, a dual chamber reactor (two sections or compartments for processing wafers positioned adjacent to each other) may be used, wherein reactant gases and inert gases may be supplied through shared lines, while precursor gases are supplied through non-shared lines.

[0050] The exemplary embodiments disclosed above do not limit the scope of the present invention, because these embodiments are merely examples of embodiments of the present invention. Any equivalent embodiments are within the scope of the present invention. In fact, various modifications of the present disclosure, such as alternative useful combinations of the described elements, will become apparent to those skilled in the art from the description, except those shown and described herein. Such modifications and embodiments are also intended to fall within the scope of the appended claims.

Claims

1. A method for filling a trench on a substrate, comprising the following steps: Positioning a substrate on a substrate support, the substrate support being disposed in a reaction chamber, wherein a pressure in the reaction chamber is less than 200 Pa; continuously flowing a carbon precursor into a reaction chamber; continuously flowing an etching gas into the reaction chamber; generating a plasma in the reaction chamber by applying a first radio frequency (RF) power to one of the one or more electrodes in the reaction chamber; as well as An amorphous carbon layer is deposited in the trenches on the substrate.

2. The method according to claim 1, wherein: The substrate support is maintained at a temperature between about 350°C and about 550°C.

3. The method according to claim 1, wherein: The first RF power is continuously applied.

4. The method according to claim 1, wherein: The first RF power is less than 2000W.

5. The method according to claim 1, wherein: The frequency of the first RF is between 10 MHz and 30 MHz.

6. The method according to claim 1, wherein: A second RF power is applied to one of the one or more electrodes of the reaction chamber.

7. The method according to claim 6, wherein: The second RF power is less than 500W.

8. The method according to claim 5, wherein: The frequency of the second RF is between 100 KHz and 1000 KHz.

9. The method according to claim 1, wherein: The flow rate of the carbon precursor is between 10 and 200 sccm.

10. The method according to claim 1, wherein: The carbon precursor includes one of the following: CH4, C2H2, C3H8, C4H10, C2H4, C3H6, C4H8, C5H10, C9H12, C6H11N3, C10H12O2 or a combination thereof.

11. The method according to claim 1, wherein: The etching gas includes one of the following: H2, He, O2, CO2, NH3, N2O or a combination thereof.

12. The method according to claim 11, wherein: The flow rate of the etching gas is between 5 and 200 sccm.

13. The method according to claim 1, wherein: One of the electrodes is part of the substrate support.

14. The method according to claim 1, wherein: The elastic modulus of the amorphous carbon layer is greater than 20 GPa.

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