Method for growing reflective films

Abstract

Methods and apparatus for forming a reflective film are described herein. A liner is formed on a substrate surface, followed by a reflective layer, such that there is no oxygen exposure between the formation of the liner and the reflective layer. In some embodiments, a high aspect ratio structure is filled with a reflective material by partially filling the structure with a reflective material while inhibiting growth on top of the structure, reactivating the top of the substrate, and then filling the structure with a reflective material.

Description

Technical Field

[0001] Various embodiments of the present disclosure generally relate to the formation of a reflective layer. Specifically, various embodiments of the present disclosure provide methods and apparatus for growing a reflective film in a high aspect ratio (HAR) structure. Background Art

[0002] Many modern electronic imaging devices, such as those found in digital cameras, computers, and cell phones, use digital image sensors that include an array of pixels. The pixels convert light into an electrical charge. However, some of the light received by the pixels is not absorbed and is passed to underlying device components. In some devices, the unabsorbed light can scatter into adjacent pixels, causing crosstalk. The unabsorbed light and the crosstalk or scattered light can reduce the accuracy and life of the pixels.

[0003] To minimize or prevent crosstalk, individual pixels of a contact image sensor (CIS) are isolated from adjacent pixels by a structure / technology called deep trench isolation (DTI). Deep trench isolation uses a high aspect ratio structure formed in the substrate surface between the light sensing areas of the CIS. Deep trench isolation typically uses a stack of reflective materials to reduce optical crosstalk between adjacent pixels and thereby improve the quantum efficiency of the CIS. The reflective material must be highly reflective to provide good optical isolation.

[0004] Additionally, growing metal films such as aluminum by chemical vapor deposition (CVD) can be a difficult task due to metal selectivity to the substrate. For example, CVD aluminum does not grow, or exhibits only minimal growth, even on substrates slightly exposed to air.

[0005] In addition, it may be difficult to form a film in the bottom of a high aspect ratio structure. As shown in FIG1 , in some high aspect ratio DTI structures 10, the top portion 12 of the structure 10 is filled with a reflective material 16, while the bottom portion 14 of the structure remains unfilled. The unfilled portion reduces the effectiveness of pixel isolation.

[0006] Therefore, there is a need for methods for depositing reflective materials and methods for improving DTI in high aspect ratio structures. Summary of the invention

[0007] One or more embodiments of the present disclosure are directed to a method of forming a reflective film stack. A liner is formed on a substrate, and a reflective layer is formed on the liner. The reflective layer is formed in the same processing tool as the liner without being exposed to oxygen in between.

[0008] A number of other embodiments of the present disclosure are directed to methods of forming a reflective film stack. A conformal liner is formed on a substrate having at least one structure formed therein. The at least one structure has a bottom and sidewalls. The substrate is exposed to a growth inhibitor to deactivate a top portion of the substrate. A reflective layer is formed on the liner within the at least one structure to a suppressed thickness. The top portion of the substrate is reactivated. The at least one structure is filled with a reflective layer.

[0009] Several other embodiments of the present disclosure are directed to a non-transitory computer-readable medium comprising instructions that, when executed by a controller of a processing tool, cause the processing tool to: deposit a conformal liner on a substrate in a first processing chamber connected to a central transfer station having a robot therein; move the substrate from the first processing chamber to a second processing chamber connected to the central transfer station such that the substrate is not exposed to oxygen; expose the substrate to a growth inhibitor in one or more of the first processing chamber, the central transfer station, or the second processing chamber; form a reflective layer on the liner in the second processing chamber; and expose the substrate to a reactivating agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to understand the above structure of the present disclosure in detail, the present disclosure briefly summarized above can be described in more detail with reference to multiple embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only show multiple typical embodiments of the present disclosure and therefore should not be considered as limiting the scope of the present disclosure, because the present disclosure may allow for other multiple equivalent embodiments.

[0011] FIG. 1 shows a prior art CIS with an unpopulated bottom segment;

[0012] Figure 2 shows a membrane stack according to one or more embodiments of the present disclosure;

[0013] Figures 3A to 3G illustrates a process for forming a reflective stack according to one or more embodiments of the present disclosure; and

[0014] Figure 4 A processing tool is shown for use with a method according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0015] Before describing several exemplary embodiments of the present disclosure, it should be understood that the present disclosure is not limited to the details of construction or processing steps set forth in the following description. The present disclosure is capable of many other embodiments and can be practiced or carried out in various ways.

[0016] As used in this specification and the appended claims, the term "substrate" refers to a surface or portion of a surface on which a process acts. Those skilled in the art will also understand that references to a substrate may also refer to only portions of a substrate unless the context clearly indicates otherwise. In addition, references to depositing on a substrate may mean both a bare substrate and a substrate on which one or more films or structures are deposited or formed.

[0017] As used herein, "substrate" refers to any substrate or material surface formed on a substrate on which film processing is performed during a manufacturing process. For example, substrate surfaces that may be processed include materials such as silicon, silicon oxide, strained silicon, silicon on insulator (SOI), carbon-doped silicon oxide, amorphous silicon, doped silicon, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive materials, depending on the application. Substrates include, but are not limited to, semiconductor wafers. The substrate may be exposed to a pretreatment process to polish, etch, reduce, oxidize, hydroxylate, anneal, UV cure, electron beam cure, and / or bake the substrate surface. In addition to performing film processing directly on the surface of the substrate itself, in the present disclosure, as disclosed in more detail below, any film processing step disclosed may also be performed on an underlying layer formed on the substrate, and the term "substrate surface" is intended to include such underlying layers as indicated by the context. Thus, for example, where a film / layer or portion of a film / layer has been deposited on a substrate surface, the exposed surface of the newly deposited film / layer becomes the substrate surface.

[0018] Some embodiments of the present disclosure relate to methods for growing aluminum (Al) thin films by chemical vapor deposition (CVD). Some embodiments advantageously provide methods for growing metal films on substrates without regard to chemical termination. As a first deposition on a substrate in one deposition chamber, a liner film is used to grow the CVD aluminum film of some embodiments. According to some embodiments, the substrate with the liner is transferred to a second deposition chamber under high vacuum to grow a metal film with good reflectivity.

[0019] One or more embodiments of the present disclosure provide an effective method for optically isolating pixels in contact image sensors. In some embodiments, the deposited metal film (e.g., CVD aluminum) has a high reflectivity. The metal film of some embodiments is used to fill the gaps between pixels, thereby preventing or minimizing pixel crosstalk. Some embodiments provide methods for deep trench isolation with a higher signal-to-noise ratio than current methods. Some embodiments provide methods for providing enhanced device performance for deep trench isolation.

[0020] Some embodiments of the present disclosure advantageously provide methods for growing CVD aluminum films with excellent growth behavior. In some embodiments, a liner material (e.g., TiAlC) provides an excellent surface for aluminum growth. In some embodiments, using TiAlC as a liner material, in-situ CVD aluminum can be deposited on a substrate commonly used in semiconductor manufacturing. Some embodiments advantageously provide methods for metal gap filling that can completely fill a trench with an aspect ratio of 50:1. Some embodiments provide gap filling methods with no or minimal seams or holes.

[0021] In contact image sensor (CIS) applications, tungsten (W) is conventionally used for deep trench isolation (DTI) of pixels. One or more embodiments of the present disclosure provide methods for depositing high reflectivity CVD films (eg, CVD Al films) to replace tungsten to enhance device performance.

[0022] In some embodiments, liner selection affects CVD aluminum film growth. Some embodiments of the present disclosure provide methods for depositing ALD TiAlC liners by clustering multiple deposition chambers without breaking vacuum, thereby enabling sample transfer between chambers under high vacuum. In some embodiments, the ALD TiAlC liner is formed by alternating exposure to titanium precursors and aluminum precursors. In some embodiments, the ALD TiAlC deposition process ends with titanium precursor exposure as the last reactant species.

[0023] In some embodiments, exposure of the liner to air inhibits CVD Al film growth.Some embodiments of the present disclosure provide methods for forming CVD Al films with good deposition rate, resistivity, and / or reflectivity.

[0024] In some embodiments, a contact image sensor deep trench with an aspect ratio of 50:1 (~100nm opening and 5μm deep) is filled with CVD Al. Unlike conventional CVD processes that use continuous feeds; some embodiments separate the 5-10 second feeds with a 10-20 second purge between each feed. In some embodiments, the total film thickness is controlled by repeating multiple feed-purge cycles. In some embodiments, the inventors surprisingly found that separating the feeds by purge allows for complete filling of 50:1 aspect ratio structures with no seams and minimal voids.

[0025] Some embodiments provide methods for fully filling high aspect ratios (e.g., >100:1) with minimal or no seams or voids. According to some embodiments, a surface treatment is used to inhibit metal film deposition on the top portion of the trench, thereby filling the bottom portion of the trench. A second surface treatment activates the top portion of the trench for metal film deposition, thereby producing a complete gap fill.

[0026] Reference Figure 2 , one or more embodiments of the present disclosure are directed to a method of forming a reflective film stack 100. A liner 110 is formed on a surface 106 of a substrate 105. The liner 110 may have any suitable composition and may be deposited by any suitable technique known to those skilled in the art. In some embodiments, the liner 110 is deposited by chemical vapor deposition (CVD). In some embodiments, the liner 110 is deposited by atomic layer deposition (ALD). In some ALD depositions, the liner 110 forms a conformal film on the substrate surface 106. As used herein, a "conformal" film refers to a film having approximately the same thickness along the deposition. For example, in a trench formed in a substrate, the conformal film has approximately the same thickness at the top of the trench as at the bottom of the trench. When used in this manner, the term "approximately the same thickness" refers to a thickness variation of no more than ±15%, ±10%, ±7.5%, ±5%, or ±2.5% relative to the average film thickness.

[0027] In some embodiments, the liner 110 comprises titanium aluminum carbide (TiAlC). Those skilled in the art will recognize that the use of chemical formulas for film components does not imply any particular stoichiometric relationship. For example, titanium aluminum carbide (TiAlC) films are not limited to films having 1:1:1 Ti:Al:C atoms. Rather, chemical formulas are used only to qualitatively indicate the composition of the film. For example, a TiAlC film is composed of titanium, aluminum, and carbon atoms in any appropriate proportion. In some embodiments, the liner 110 is substantially composed of TiAlC. When used in this manner, the term "substantially composed of..." is measured in atoms, and the composition of the target film is greater than or equal to 95%, 98%, 99%, or 99.5% of the sum of the elements. In some embodiments, the liner 110 comprises one or more of titanium (Ti), tantalum (Ta), cobalt (Co), nickel (Ni), molybdenum (Mo), or aluminum (Al) or is substantially composed of them. In some embodiments, the liner 110 comprises or consists essentially of titanium aluminum carbide (TiAlC) or one or more of titanium (Ti), tantalum (Ta), cobalt (Co), nickel (Ni), molybdenum (Mo), or aluminum (Al). In some embodiments, the liner 110 comprises or consists essentially of one or more of titanium (Ti), tantalum (Ta), cobalt (Co), nickel (Ni), molybdenum (Mo), aluminum (Al), or carbon (C).

[0028] In some embodiments, the liner 110 comprises titanium. In some embodiments, the liner 110 consists essentially of titanium. In some embodiments, the titanium is deposited by ALD using one or more of titanium tetrachloride (TiCl4), tetrakis(dimethylamino)titanium (TDMAT), or a mixture of TiCl4 and 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene. In some embodiments, the titanium precursor comprises titanium tetrachloride (TiCl4) or consists essentially of titanium tetrachloride (TiCl4). As used herein, when referring to a reactive gas or precursor, the term "consisting essentially of..." means that the reactive species constitutes greater than or equal to 95%, 98%, 99%, or 99.5% of the compound in the reactive gas composition. Dilution gases, carrier gases, and inert gases are not included in the calculation of the reactive species composition. In some embodiments, the titanium precursor comprises or consists essentially of tetrakis(dimethylamino)titanium (TDMAT). In some embodiments, the titanium precursor comprises or consists essentially of 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene.

[0029] In some embodiments, the liner 110 comprises tantalum. In some embodiments, the liner 110 consists essentially of tantalum. In some embodiments, the tantalum is deposited by ALD using one or more of TaCl5 or pentakis(diemthylamino)tantalum (PDMAT). In some embodiments, the tantalum precursor comprises or consists essentially of TaCl5. In some embodiments, the tantalum precursor comprises or consists essentially of pentakis(diemthylamino)tantalum (PDMAT).

[0030] In some embodiments, the liner 110 comprises cobalt. In some embodiments, the liner 110 consists essentially of cobalt. In some embodiments, the cobalt is deposited by ALD using dicobalt hexacarbonyltert-butylacetylene (CCTBA). In some embodiments, the cobalt precursor comprises dicobalt hexacarbonyltert-butylacetylene (CCTBA). In some embodiments, the cobalt precursor consists essentially of dicobalt hexacarbonyltert-butylacetylene (CCTBA).

[0031] In some embodiments, the liner 110 comprises nickel. In some embodiments, the liner 110 consists essentially of nickel. In one or more embodiments, the nickel is deposited by ALD using tetrakis(trifluorophosphine)nickel (Ni(PF3)4). In some embodiments, the nickel precursor comprises tetrakis(trifluorophosphine)nickel (Ni(PF3)4). In some embodiments, the nickel precursor consists essentially of tetrakis(trifluorophosphine)nickel (Ni(PF3)4).

[0032] In one or more embodiments, the liner 110 comprises aluminum. In some embodiments, the liner 110 consists essentially of aluminum. In some embodiments, the aluminum is deposited by ALD using one or more of dimethylaluminum hydride (DMAH), triethylaluminum (TEA), or trimethylaluminum (TMA). In one or more embodiments, the aluminum precursor comprises dimethylaluminum hydride (DMAH). In some embodiments, the aluminum precursor consists essentially of dimethylaluminum hydride (DMAH). In one or more embodiments, the aluminum precursor comprises triethylaluminum (TEA). In some embodiments, the aluminum precursor consists essentially of triethylaluminum (TEA). In one or more embodiments, the aluminum precursor comprises trimethylaluminum (TMA). In some embodiments, the aluminum precursor consists essentially of trimethylaluminum (TMA).

[0033] The liner 110 can be deposited at any suitable temperature. In some embodiments, the liner 110 is deposited at a temperature in a range of about 300°C to about 500°C.

[0034] The liner 110 may have any suitable thickness depending on, for example, the species used in the composition of the liner 110, the substrate 105, and / or the metal film 120 to be deposited on top of the liner 110. In one or more embodiments, the liner 110 has a thickness sufficient to form a continuous film. As used herein, the term "continuous" refers to a layer or film that covers the entire exposed surface without gaps or bare spots that reveal underlying material of the deposited layer. In some embodiments, the liner 110 has a thickness of at least about 100 mm / s. to Thickness within the range.

[0035] In some embodiments, the reflective layer 120 is formed on the liner 110 or directly on the liner 110. When used in this manner, the term "formed directly on..." means that there is no intermediate layer between the layers. In some embodiments, after the liner 110 is formed, the reflective layer 120 is formed without being exposed to oxygen in between. The term "not exposed to oxygen" means that the underlying film (e.g., the liner 110) is not exposed to an environment in which an oxide of the underlying film is formed. For example, before the reflective layer 120 is formed, the liner 110 is not exposed to air, water, water vapor, oxygen, ozone, peroxide, etc.

[0036] The reflective layer 120 may be formed by any suitable technique including but not limited to ALD, CVD, plasma enhanced ALD, plasma enhanced CVD, physical vapor deposition (PVD). In some embodiments, the liner 110 is formed by an ALD process and the reflective layer 120 is formed by a CVD process.

[0037] The reflective layer 120 of some embodiments is formed in the same processing chamber as the liner 110. In some embodiments, the reflective layer 120 is formed in a different processing chamber than the liner 110. In some embodiments, the reflective layer 120 is formed in the same processing tool as the liner 110. As described further below, a "processing tool," also referred to as a cluster tool, is a processing tool having multiple processing chambers connected to a transfer station.

[0038] The reflective layer 120 of some embodiments comprises one or more of aluminum, tungsten, molybdenum, or copper. In some embodiments, the reflective layer consists essentially of one or more of aluminum, tungsten, molybdenum, or copper. In some embodiments, the reflective layer 120 has a different composition than the liner 110. In some embodiments, the reflective layer 120 has a different element than the liner 110. In some embodiments, the reflective layer 120 and the liner 110 have one or more common elements and different compositions.

[0039] In some embodiments, the reflective layer 120 comprises aluminum or consists essentially of aluminum. In some embodiments, the aluminum is deposited by one or more of ALD or CVD using one or more of dimethylaluminum hydride (DMAH), triethylaluminum (TEA), or trimethylaluminum (TMA). In some embodiments, the aluminum is deposited by CVD using DMAH. In some embodiments, the aluminum is deposited by CVD using TEA. In some embodiments, the aluminum is deposited by CVD using TMA. In some embodiments, the aluminum precursor used to deposit the reflective layer 120 comprises DMAH or consists essentially of DMAH. In some embodiments, the aluminum precursor used to deposit the reflective layer 120 comprises TEA or consists essentially of TEA. In some embodiments, the aluminum precursor used to deposit the reflective layer 120 comprises TMA or consists essentially of TMA.

[0040] In some embodiments, the reflective layer 120 includes or consists essentially of tungsten. In some embodiments, the tungsten is deposited by one or more of ALD or CVD using tungsten pentachloride (WCl5). In some embodiments, the tungsten precursor used to form the reflective layer 120 includes or consists essentially of tungsten pentachloride.

[0041] In some embodiments, the reflective layer 120 comprises molybdenum or consists essentially of molybdenum. In some embodiments, the molybdenum is deposited by one or more of ALD or CVD using one or more of molybdenum pentachloride (MoCl5) or molybdenum dioxide dichloride (MoO2Cl2). In some embodiments, the molybdenum is deposited by CVD using molybdenum pentachloride. In some embodiments, the aluminum is deposited by CVD using molybdenum dioxide dichloride. In some embodiments, the molybdenum precursor used to deposit the reflective layer 120 comprises molybdenum pentachloride or consists essentially of molybdenum pentachloride. In some embodiments, the molybdenum precursor used to deposit the reflective layer 120 comprises molybdenum dioxide dichloride or consists essentially of molybdenum dioxide dichloride.

[0042] In some embodiments, the reflective layer 120 comprises or consists essentially of copper. In some embodiments, the copper is deposited by one or more of ALD or CVD using one or more of copper (I) chloride (CuCl) or copper (II) chloride (CuCl2). In some embodiments, the copper is deposited by CVD using copper (I) chloride. In some embodiments, the copper is deposited by CVD using copper (II) chloride. In some embodiments, the copper precursor used to deposit the reflective layer 120 comprises or consists essentially of copper (I) chloride. In some embodiments, the copper precursor used to deposit the reflective layer 120 comprises or consists essentially of copper (II) chloride.

[0043] In some embodiments, the reflective layer 120 is deposited at a temperature in the range of 100° C. to 500° C., or in the range of 150° C. to 450° C., or in the range of 200° C. to 400° C. In some embodiments, the reflective layer 120 is deposited at a pressure in the range of 0.5 Torr to 100 Torr, or in the range of about 1 Torr to about 50 Torr, or in the range of 5 Torr to 25 Torr.

[0044] Now refer to Figures 3A to 3G One or more embodiments of the present disclosure are directed to a method of forming a reflective film stack on a structured substrate 200. The structured substrate 200 is a substrate having at least one structure (also referred to as a feature structure) formed in the substrate. Figure 3A As shown in , some embodiments of the structure 202 include at least one sidewall 203 and a bottom 204. In the illustrated embodiment, the structure 202 has a tapered cross-section that extends a depth D from the top surface 201 of the structured substrate 200 to the bottom 204. The width W of the structure 202 is measured at the top surface 201 of the substrate 200. In some embodiments, the aspect ratio of the structure 202 measured as the depth D of the structure 202 to the width W is greater than 50:1. In some embodiments, the aspect ratio of the structure 202 is greater than 60:1, 70:1, 80:1, 90:1, or 100:1. The particular shape of the structure 202 shown only represents one possible shape and should not be considered to limit the scope of the present disclosure. The number of sidewalls 203 on the structure 202 depends on the shape of the structure 202 and should not be considered to limit the scope of the present disclosure.

[0045] like Figure 3B As shown, conformal liner 210 is formed on substrate 200 and at least one structure 202. Conformal liner 210 may be any material and may be formed by any of the processes previously described.

[0046] like Figure 3C As shown in , after the conformal liner 210 is deposited, the substrate 200 is exposed to a growth inhibitor. The growth inhibitor of some embodiments passivates the top surface 201 of the substrate 200, thereby forming a passivation liner 220. At this point, the top surface 201 of the substrate 200 includes the conformal liner 210. In other words, the growth inhibitor of some embodiments passivates the conformal liner 210 on the top surface 201 of the substrate 200. In some embodiments, the growth inhibitor passivates the top portion 212 of the conformal liner 210 in the structure 202. In some embodiments, the growth inhibitor passivates the top portion of the substrate. When used in this manner, the top portion of the substrate 200 refers to the top surface 201 of the substrate 200 and the top 206 of the structure 202. The growth inhibitor of some embodiments passivates the conformal liner 210 to a depth D from the top surface 201 of the substrate 200. d The depth D of the passivation liner 220 in some embodiments isd In the range of 10% to 90% or 20% to 80% or 30% to 70% or 40% to 60% or about 50% of the depth D of the structure 202 .

[0047] Some embodiments of the growth inhibitor include a compound that reacts with the liner 210 to form a surface or material that is unfavorable for the deposition of the reflective layer material. In some embodiments, the growth inhibitor includes a carbon-based material. In some embodiments, the growth inhibitor includes TEA or consists essentially of TEA.

[0048] exist Figure 3D In the embodiment, the reflective layer 230 is formed on the conformal liner 210 within the at least one structure 202. The reflective layer 230 is formed to have a suppressed thickness T measured from the conformal liner 210 on the bottom 204 of the structure 202. r In some embodiments, the suppressed thickness T r In the range of 10% to 90% or 20% to 80% or 30% to 70% or 40% to 60% or about 50% of the depth D of the structure 202. In some embodiments, the suppressed thickness T r The depth D is sufficient to allow the top surface 232 of the reflective layer 230 to reach the passivation liner 220. d In some embodiments, the suppressed thickness T r Less than the thickness reaching the passivation liner 220. In some embodiments, the suppressed thickness T r The top surface 232 of the reflective layer 230 is brought to the top portion 206 of the structure, within the area of ​​the structure 206 defined by the passivation liner 220 .

[0049] In some embodiments, Figure 3E As shown, the top portion 206 of the substrate 200 is reactivated to replace the passivation liner 220 with the conformal liner 210. In some embodiments, the substrate is reactivated by exposing the substrate surface to titanium tetrachloride under the same temperature and processing conditions as the liner deposition.

[0050] like Figure 3F As shown, according to some embodiments, structure 202 is filled with a reflective layer 230. In some embodiments, reflective layer 230 is deposited to form a capping layer 235 on the top surface of substrate 200. In some embodiments, capping layer 235 is on conformal liner 210 on substrate 200. In some embodiments, capping layer 235 is directly on substrate 200 without conformal liner 210.

[0051] Figure 3G A substrate 200 is shown having a reflective layer 230 deposited onto a top surface 201 of the substrate 200. In some embodiments, Figure 3FThe capping layer 235 shown in FIG. 2 is removed by any suitable technique to expose the top surface of the substrate 200 and the top surface 211 of the conformal liner 210 within the structure 202. In some embodiments, the capping layer 235 is removed to lower the top surface 232 of the reflective layer 230 to be flush with the top surface 211 of the conformal liner 210. In some embodiments, the conformal liner 210 covers the top surface 201 of the substrate 200, and the reflective layer 230 has a top surface 232 that is flush with the top surface 211 of the conformal liner 210. In some embodiments, the capping layer 235 and optionally the conformal liner 210 on the top surface 201 of the substrate 200 are removed by one or more of chemical-mechanical planarization (CMP) or etching.

[0052] Various other embodiments of the present disclosure are directed to a processing tool 900 for forming a device and practicing the described methods, such as Figure 4 The processing tool 900, also known as a cluster tool, includes at least one central transfer station 921, 931 having multiple sides. Robots 925, 935 are located in the central transfer station 921, 931 and are configured to move a robot blade and a wafer to each of the multiple sides.

[0053] The processing tool 900 includes a plurality of processing chambers 902, 904, 906, 908, 910, 912, 914, 916, and 918, also referred to as processing stations, connected to a central transfer station. Each processing chamber provides an independent processing area isolated from an adjacent processing station. The processing chamber can be any suitable chamber, including but not limited to a physical vapor deposition chamber, a UV curing chamber, an ICP chamber, an etching chamber, and the like. The specific arrangement of the processing chambers and components may vary depending on the cluster tool and should not be considered to limit the scope of the present disclosure.

[0054] In some embodiments, the processing tool 900 includes at least one atomic layer deposition chamber connected to a central transfer station. In some embodiments, the processing tool 900 includes at least one chemical vapor deposition chamber connected to a central transfer station.

[0055] exist Figure 4 In the illustrated embodiment, the factory interface 950 is connected to the front of the processing tool 900. The factory interface 950 includes a loading chamber 954 and an unloading chamber 956 on the front 951 of the factory interface 950. Although the loading chamber 954 is shown on the left and the unloading chamber 956 is shown on the right, those skilled in the art will understand that this represents only one possible configuration.

[0056] The size and shape of the loading chamber 954 and unloading chamber 956 may vary depending, for example, on the substrates being processed in the processing tool 900. In the illustrated embodiment, the loading chamber 954 and unloading chamber 956 are sized to hold a wafer cassette with a plurality of wafers positioned within the cassette.

[0057] The robot 952 is within the factory interface 950 and can move between the loading chamber 954 and the unloading chamber 956. The robot 952 can transfer wafers from a cassette in the loading chamber 954 to a load lock chamber 960 via the factory interface 950. The robot 952 can also transfer wafers from a load lock chamber 962 to a cassette in the unloading chamber 956 via the factory interface 950. One skilled in the art will appreciate that the factory interface 950 can have more than one robot 952. For example, the factory interface 950 can have a first robot that transfers wafers between the loading chamber 954 and the load lock chamber 960, and a second robot that transfers wafers between the load lock 962 and the unloading chamber 956.

[0058] The processing tool 900 shown has a first section 920 and a second section 930. The first section 920 is connected to the factory interface 950 via the load lock chambers 960, 962. The first section 920 includes a first transfer chamber 921, wherein at least one robot 925 is positioned in the first transfer chamber. The robot 925 is also referred to as a robotic wafer transfer mechanism. The first transfer chamber 921 is centrally located relative to the load lock chambers 960, 962, the processing chambers 902, 904, 916, 918 and the buffer chambers 922, 924. The robot 925 of some embodiments is a multi-arm robot capable of independently moving more than one wafer at a time. In some embodiments, the first transfer chamber 921 includes more than one robotic wafer transfer mechanism. The robot 925 in the first transfer chamber 921 is configured to move wafers between chambers around the first transfer chamber 921. Individual wafers are carried on a wafer transfer blade located at a remote end of the first robotic mechanism.

[0059] After processing the wafer in the first section 920, the wafer may be transferred to the second section 930 via a transfer chamber. For example, the chambers 922, 924 may be one-way or two-way transfer chambers. The transfer chambers 922, 924 may be used, for example, to cryogenically cool the wafer prior to processing in the second section 930, or to allow for wafer cooling or post-processing prior to returning to the first section 920.

[0060] The system controller 990 communicates with the first robot 925, the second robot 935, the first plurality of process chambers 902, 904, 916, 918, and the second plurality of process chambers 906, 908, 910, 912, 914. The system controller 990 may be any suitable component that can control the process chambers and the robots. For example, the system controller 990 may be a computer including a central processing unit (CPU) 992, a memory 994, an input / output (I / O) 996, and support circuits 998. The controller 990 may control the process tool 900 directly or via a computer (or controller) associated with a particular process chamber and / or support system component.

[0061] In one or more embodiments, the controller 990 may be one of any form of general purpose computer processor that may be used in an industrial environment to control various chambers and subprocessors. The memory 994 or computer readable medium of the controller 990 may be one or more of readily available memories such as non-transitory memory (e.g., random access memory (RAM)), read-only memory (ROM), floppy disk, hard disk, optical storage media (e.g., compact disk or digital video disk), flash drive, or any other form of local or remote digital storage. The memory 994 may retain a set of instructions that may be operated by the processor (CPU 992) to control the parameters and components of the processing tool 900.

[0062] Support circuits 998 are coupled to the CPU 992 for supporting the processor in a conventional manner. These circuits include caches, power supplies, clock circuits, input / output circuits and subsystems, and the like. One or more processes may be stored in the memory 994 as software routines that, when executed or called by the processor, cause the processor to control the operation of the processing tool 900 or individual processing units in the manner described herein. The software routines may also be stored and / or executed by a second CPU (not shown) located remotely from the hardware controlled by the CPU 992.

[0063] Some or all of the processes and methods of the present disclosure may also be performed in hardware. Thus, the processes may be implemented in software and executed in hardware (such as, for example, an application specific integrated circuit or other type of hardware implementation or as a combination of software and hardware) using a computer system. The software routines, when executed by a processor, convert a general purpose computer into a special purpose computer (controller) that controls chamber operations to perform the processes.

[0064] In some embodiments, the controller 990 has one or more configurations to perform individual processes or sub-processes to perform the method. The controller 990 may be connected to an intermediate component and configured to operate the intermediate component to perform the functions of the method. In some embodiments, the controller 990 is connected to one or more of an atomic layer deposition chamber or a chemical vapor deposition chamber and configured to control one or more of the atomic layer deposition chamber or the chemical vapor deposition chamber.

[0065] The process may generally be stored as a software routine in the memory 994 of the system controller 990, which, when executed by the processor, causes the processing chamber to perform the process of the present disclosure. The software routine may also be stored and / or executed by a second processor (not shown) located remotely from the hardware controlled by the processor. Some or all of the methods of the present disclosure may also be performed in hardware. Thus, the process may be implemented in software and executed in hardware (such as, for example, an application specific integrated circuit or other type of hardware implementation or a combination of software and hardware) using a computer system. The software routine, when executed by the processor, converts a general purpose computer into a special purpose computer (controller) that controls the operation of the chamber to perform the process.

[0066] In one or more embodiments, a processing tool includes: a central transfer station including a robot configured to move wafers; a plurality of processing stations, each processing station connected to the central transfer station and providing a processing area separate from a processing area of ​​an adjacent processing station, the processing stations including a physical vapor deposition chamber and a remote plasma source; a UV curing chamber; an ICP chamber; and a controller connected to the central transfer station and the plurality of processing stations, the controller configured to activate the robot to move wafers between the processing stations and to control processing occurring in each of the processing stations.

[0067] In some embodiments, the controller 990 has one or more of the following: a structure for moving a substrate from a central transfer station to at least one deposition chamber; a structure for moving a substrate from at least one deposition chamber to the central transfer station; a structure for forming a conformal liner on a substrate in an atomic layer deposition chamber; a structure for exposing a substrate to a growth inhibitor; a structure for forming a first portion of a reflective layer; a structure for exposing a substrate to a material to reactivate the substrate; and a structure for forming a second portion of a reflective layer.

[0068] Some embodiments of the present disclosure are directed to a non-transitory computer-readable medium comprising instructions that, when executed by a controller of a processing chamber, cause the processing chamber to operate to: deposit a conformal liner on a substrate in a first processing chamber connected to a central transfer station having a robot therein; move the substrate from the first processing chamber to a second processing chamber connected to the central transfer station such that the substrate is not exposed to oxygen; expose the substrate to a growth inhibitor in one or more of the first processing chamber, the central transfer station, or the second processing chamber; form a reflective layer on the liner in the second processing chamber; and expose the substrate to a reactivation agent.

[0069] Throughout this specification, references to "one embodiment," "certain embodiments," "one or more embodiments," or "an embodiment" mean that the particular structures, structures, materials, or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present disclosure. Thus, throughout this specification, phrases such as "in one or more embodiments," "certain embodiments," "in an embodiment," or "in an embodiment" appearing in various places do not necessarily refer to the same embodiment of the present disclosure. Furthermore, in one or more embodiments, particular structures, structures, materials, or characteristics may be combined in any suitable manner.

[0070] Although the present disclosure has been described herein with reference to a plurality of specific embodiments, it will be appreciated by those skilled in the art that the described plurality of embodiments are merely illustrations of the principles and applications of the present disclosure. It will be apparent to those skilled in the art that various modifications and variations may be made to the methods and apparatus of the present disclosure without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure may include modifications and variations within the scope of the appended claims and the equivalents of the appended claims.

Claims

1. A method for forming a reflective film stack, the method comprising the following steps: forming a pad on a substrate having a structure formed therein; exposing the substrate to a growth inhibitor to passivate a top portion of the substrate and form a passivated liner; forming a reflective layer on the passivated liner within the structure to an inhibited thickness in a range of 10% to 90% of the depth of the structure, the reflective layer being formed in the same processing tool as the liner without intermediate exposure to oxygen; reactivating the top portion of the substrate by exposing the substrate surface to titanium tetrachloride; and The structure is filled with the reflective layer.

2. The method of claim 1, wherein the liner comprises titanium aluminum carbide or one or more of the following: titanium (Ti), tantalum (Ta), cobalt (Co), nickel (Ni), molybdenum (Mo), or aluminum (Al).

3. The method of claim 2, wherein the liner comprises titanium and is deposited using TiCl4, tetrakis(dimethylamino)titanium (TDMAT), or a mixture of TiCl4 and 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene.

4. The method of claim 2, wherein the liner comprises tantalum and is deposited using one or more of TaCl5 or penta(dimethylamino)tantalum (PDMAT).

5. The method of claim 2, wherein the liner comprises cobalt and is deposited using dicobalt hexacarbonyl tert-butylacetylene (CCTBA).

6. The method of claim 2, wherein the liner comprises nickel and is deposited using nickel tetrakis(trifluorophosphine) (Ni(PF3)4).

7. The method of claim 2, wherein the liner comprises aluminum and is deposited using one or more of dimethylaluminum hydride (DMAH), triethylaluminum (TEA), or trimethylaluminum (TMA).

8. The method of claim 2, wherein the pad has to Thickness within the range.

9. The method of claim 1, wherein the reflective layer comprises one or more of aluminum, tungsten, molybdenum, or copper.

10. The method of claim 9, wherein the reflective layer has a different composition than the liner.

11. The method of claim 9, wherein the reflective layer comprises aluminum and is deposited using one or more of dimethylaluminum hydride (DMAH), triethylaluminum (TEA), or trimethylaluminum (TMA).

12. The method of claim 9, wherein the reflective layer comprises tungsten and is deposited using tungsten pentachloride (WCl5).

13. The method of claim 9, wherein the reflective layer comprises molybdenum and is deposited using one or more of molybdenum pentachloride (MoCl5) or molybdenum dioxide dichloride (MoO2Cl2).

14. The method of claim 9, wherein the reflective layer comprises copper and is deposited using one or more of copper (I) chloride (CuCl) or copper (II) chloride (CuCl2).

15. A method for forming a reflective film stack, the method comprising the following steps: forming a conformal liner on a substrate having at least one structure formed therein, the at least one structure having a bottom and sidewalls; exposing the substrate to a growth inhibitor to passivate a top portion of the substrate; forming a reflective layer on the pad within the at least one structure to a suppressed thickness, the suppressed thickness being in a range of 10% to 90% of the depth of the at least one structure; reactivating the top portion of the substrate by exposing the substrate surface to titanium tetrachloride; and The at least one structure is filled with the reflective layer.

16. The method of claim 15, wherein the liner comprises titanium aluminum carbide or one or more of the following: titanium (Ti), tantalum (Ta), cobalt (Co), nickel (Ni), molybdenum (Mo), or aluminum (Al).

17. The method of claim 15, wherein the reflective layer comprises one or more of aluminum, tungsten, molybdenum, or copper.

18. The method of claim 15, wherein the conformal liner comprises titanium aluminum carbide, the reflective layer comprises aluminum, exposing the substrate to the growth inhibitor comprises immersing the substrate in triethylaluminum (TEA), and reactivating the top portion of the substrate comprises exposing the substrate to titanium tetrachloride (TiCl4).

19. The method of claim 15, wherein the reflective layer is formed in the same processing tool as the liner without intermediate exposure to oxygen.

20. A non-transitory computer readable medium comprising instructions that, when executed by a controller of a processing tool, cause the processing tool to: depositing a conformal liner on a substrate having a structure formed therein in a first processing chamber connected to a central transfer station having a robot therein; moving the substrate from the first processing chamber to a second processing chamber connected to the central transfer station such that the substrate is not exposed to oxygen; exposing the substrate to a growth inhibitor in one or more of the first processing chamber, the central transfer station, or the second processing chamber; forming a reflective layer on the liner within the structure to a suppressed thickness in the range of 10% to 90% of the depth of the structure in the second processing chamber; and The substrate was exposed to titanium tetrachloride.

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