Gas injection system for a process chamber

Abstract

Methods and apparatus for decoupling adjustments across substrate thickness variations and across substrate resistance variations in a gas injection system are described. A controller in a gas injection system may deposit a layer of material on a substrate by controlling a plurality of first mass flow controllers (MFCs) and a plurality of second MFCs. The controller may adjust the cross-substrate thickness variation of the material layer by controlling the plurality of first MFCs. The controller may adjust the cross-substrate resistivity variation of the material layer by controlling the plurality of second MFCs and independently of the cross-substrate thickness variation.

Description

Technical Field

[0001] The present disclosure relates generally to gas injection systems and more particularly to apparatus and methods for decoupling adjustments for cross-substrate thickness variations and cross-substrate resistivity variations. Background Art

[0002] Semiconductor devices are manufactured in a processing chamber. One or more precursor sources, dopant sources and carrier sources can be injected into the processing chamber to deposit the precursor reactants onto a substrate such as a silicon wafer. The gas injection system may include a main manifold (e.g., a main manifold) and an auxiliary manifold (e.g., an auxiliary manifold). Conventional systems may attempt to adjust the thickness of the material layer deposited on the substrate by adjusting the injector settings on the main manifold, and then adjust the surface resistivity of the material layer deposited on the substrate by adjusting the injector settings on the auxiliary manifold. However, adjusting the surface resistivity may have a negative impact on the thickness distribution of the material layer deposited on the substrate and cause interference. As a result, conventional systems may lack a mechanism to decouple the adjustment of cross-substrate thickness variation and cross-substrate resistivity variation, thereby limiting its ability to control material layer variation and provide optimal performance, yield and efficiency in the semiconductor manufacturing process. Summary of the invention

[0003] A simplified overview of the various aspects described herein is given below. This overview is not an extensive review and is not intended to identify key or important elements or to delineate the scope of the claims. The following overview merely presents some concepts in a simplified form as an introductory preface to the more detailed description provided below.

[0004] One or more aspects for independently adjusting cross-substrate thickness variation and cross-substrate resistance variation are described. In one aspect, a gas injection system may include one or more of the following: a main manifold including a plurality of first mass flow controllers (MFCs) having a first mass flow range and an auxiliary manifold including a plurality of second MFCs having a second mass flow range, wherein the second mass flow range may be different from the first mass flow range. The main manifold may be coupled to a precursor source, a dopant source, and a carrier source. The auxiliary manifold may be coupled to the dopant source and the carrier source. The system may also include a controller including one or more processors and a memory storing computer-readable instructions that, when executed by the one or more processors, cause the controller to deposit a material layer on a substrate by controlling a plurality of first MFCs and a plurality of second MFCs. The instructions may cause the controller to adjust the cross-substrate thickness variation of the material layer by controlling the plurality of first MFCs. The instructions may also adjust the cross-substrate resistivity variation of the material layer by controlling the plurality of second MFCs and independently of the cross-substrate thickness variation.

[0005] In some examples, the values ​​in the second mass flow range may be between about 1% and about 10% of the values ​​in the first mass flow range. Using an MFC with a relatively low mass flow range on an auxiliary manifold may decouple the adjustment of the flow distribution between the second MFCs on the auxiliary manifold from the adjustment of the flow distribution between the first MFCs on the main manifold. Such an application may allow adjustment of the cross-substrate resistance (i.e., resistance uniformity) without or with little change in the average substrate resistance uniformity, which is a function of the total dopant flow. The first mass flow range may not overlap with the second mass flow range. For example, the first mass flow range may be about 30 to about 110 standard liters per minute (SLM), and the second mass flow range may be about 1 to about 7 SLM. The first MFC and the second MFC may have different flow restriction structures. For example, each first MFC and each second MFC may include an inlet port, a control valve, and an outlet port. The control valve in the first position may couple the inlet port fluid to the outlet port. The control valve in the second position may decouple the inlet port from the outlet port fluid. The control valve may include a valve seat and a solenoid-actuated movable diaphragm. In the first position, the diaphragm is away from the valve seat, so that the gas can flow from the inlet port through the valve seat to the outlet port. In the second position, the diaphragm is adjacent to the valve seat, thereby inhibiting the gas from flowing from the inlet port through the valve seat to the outlet port. The inlet port may include a hole with an effective flow area, and when the control valve is in the first position, the effective flow area limits the mass flow rate of the gas from the inlet port through the control valve to the outlet port. The effective flow area of ​​the hole in each first MFC may be greater than the effective flow area of ​​the hole in each second MFC. The effective flow area in each first MFC can limit the mass flow rate within a first mass flow range, and the effective flow area in each second MFC can limit the mass flow rate within a second mass flow range. In some examples, the inlet port, control valve and outlet port in each first MFC can form a first mass flow limiting structure, which limits the mass flow rate of the gas within a first mass flow range. Similarly, the inlet port, control valve and outlet port in each second MFC can form a second mass flow limiting structure, which limits the mass flow rate of the gas within a second mass flow range. In some examples, the first and second mass flow restriction structures may include different inlet port cross-sections, different outlet port cross-sections, different inlet port diameters, different diaphragm-to-valve seat spacings, different outlet port diameters, or orifice plates with different effective flow areas. Each first MFC may be coupled to a first sensor configured to measure a first gas flow rate within a first mass flow range, and each second MFC may be coupled to a second sensor configured to measure a second gas flow rate within a second mass flow range. The second sensor may have a higher sensitivity than the first sensor. The plurality of first MFCs may include seven MFCs, and the plurality of second MFCs may include three MFCs.

[0006] On the other hand, the gas injection system may include an injection flange including a plurality of main injection ports corresponding to a plurality of first MFCs and a plurality of auxiliary injection ports corresponding to a plurality of second MFCs. The plurality of first MFCs may be configured to control the flow of precursors, dopants, and carriers to the deposition chamber through the plurality of main injection ports. The plurality of second MFCs may be configured to control the flow of dopants and carriers to the deposition chamber through the plurality of auxiliary injection ports. The controller may adjust the distribution of carrier flows to the deposition chamber through the plurality of auxiliary injection ports through the plurality of second MFCs to adjust the cross-substrate resistivity variation of the material layer. The controller may adjust the dopant distribution between the plurality of main injection ports on the main manifold and the plurality of auxiliary injection ports on the auxiliary manifold through the plurality of second MFCs to adjust the cross-substrate resistivity variation of the material layer. For example, the ratio of dopants carried by the auxiliary manifold and the main manifold may be 1 to 4. The controller may adjust the cross-substrate dopant concentration variation through the plurality of second MFCs to adjust the cross-substrate resistivity variation of the material layer.

[0007] In another aspect, the carrier source may include one or more tanks containing a carrier selected from nitrogen, hydrogen (H2), and helium. The precursor source may include one or more tanks containing a precursor selected from trichlorosilane, dichlorosilane, silane, disilane, trisilane, and silicon tetrachloride. The dopant source may include one or more tanks containing a dopant selected from germane, diborane, phosphine, arsine, and phosphorus trichloride.

[0008] On the other hand, a gas flow control method may include depositing a material layer on a substrate by controlling a plurality of first MFCs and a plurality of second MFCs in a gas injection system. The plurality of first MFCs may have a first mass flow range, and the plurality of second MFCs may have a second mass flow range, wherein the first mass flow range may be different from the second mass flow range. The plurality of first MFCs may be connected to a precursor source, a dopant source, and a carrier source through a main manifold. The plurality of second MFCs may be connected to a dopant source and a carrier source through an auxiliary manifold. The method may include adjusting a cross-substrate thickness variation of a material layer by controlling a plurality of first MFCs. The method may further include adjusting a cross-substrate resistivity variation of a material layer by controlling a plurality of second MFCs and independently of the cross-substrate thickness variation.

[0009] Additional aspects, configurations, embodiments, and examples are described in further detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In the accompanying drawings, some features are shown by way of example and not limitation. In the accompanying drawings, like numerals represent like elements.

[0011] Figure 1An example of a reactor system according to one or more illustrative aspects discussed herein is shown;

[0012] Figure 2 A schematic diagram showing an example of a gas injection system according to one or more aspects of the present disclosure;

[0013] Figure 3 A block diagram showing primary and secondary headers for decoupling adjustments for cross-substrate thickness variation and cross-substrate resistivity variation according to one or more aspects of the present disclosure;

[0014] Figure 4A shows an example graph illustrating adjustment of thickness distribution and resistivity distribution according to one or more aspects of the present disclosure;

[0015] Figure 4B Another example graph illustrating adjustment of thickness distribution and resistivity distribution according to one or more aspects of the present disclosure is shown;

[0016] Figure 4C Another example graph illustrating adjustment of thickness distribution and resistivity distribution according to one or more aspects of the present disclosure is shown;

[0017] Figure 5 An example flow chart describing a process for decoupling thickness and resistivity adjustments according to one or more aspects of the present disclosure is shown;

[0018] Figure 6 Depicts an example of a computing device that can be used to implement one or more aspects of the present disclosure; and

[0019] Fig. 7A An example mass flow metering valve of a mass flow controller (MFC) according to one or more aspects of the present disclosure is shown;

[0020] Figure 7B and 7C Top and side views of an example diaphragm seat of an MFC according to one or more aspects of the present disclosure are shown, including example effective flow areas of a primary MFC and an auxiliary MFC.

[0021] Those skilled in the art, having the benefit of this disclosure, will appreciate that the exact arrangement, size, and positioning of components in the drawings are not necessarily to scale or necessary. DETAILED DESCRIPTION

[0022] One or more aspects of the present disclosure relate to adjusting cross-substrate thickness variation and cross-substrate resistivity variation. The present disclosure generally relates to a reactor system including a gas injection system, and a method for independently adjusting thickness distribution and resistivity distribution using a gas injection system. The gas injection system can be used to process a substrate, such as a semiconductor wafer. For example, the system described herein can be used to form or grow an epitaxial layer (e.g., a dual-component and / or doped semiconductor layer) on a substrate surface. The gas injection system can be further used to provide etching chemicals to the substrate surface. For example, an exemplary system can provide a mixture of two or more gases (e.g., a precursor, a dopant source, and a carrier source) during a deposition (e.g., growth) process and / or during an etching process. Both deposition gases and etching gases can be used to grow epitaxial material layers on a substrate.

[0023] As used herein, the term "substrate" may refer to any one or more underlying materials on which a layer may be deposited. The substrate may include a bulk material, such as silicon (e.g., single crystal silicon) or other semiconductor material, and may include one or more layers, such as a natural oxide or other layer covering or located below the bulk material. The substrate may include various topologies, such as grooves, lines, etc. formed within or on at least a portion of the layer and / or bulk material of the substrate. The substrate may include one or more materials, including, for example, silicon (Si), germanium (Ge), germanium tin (GeSn), silicon germanium (SiGe), silicon germanium tin (SiGeSn), silicon carbide (SiC), or III-V semiconductor materials, such as gallium arsenide (GaAs), gallium phosphide (GaP), or gallium nitride (GaN). In some examples, the substrate may include one or more dielectric materials, including, for example, oxides, nitrides, or oxynitrides. The substrate may include silicon oxide (e.g., SiO2), metal oxides (e.g., Al2O3), silicon nitride (e.g., Si3N4), or silicon oxynitride. The substrate may also include an engineered substrate, in which a surface semiconductor layer may be disposed on a bulk support with an intermediate buried oxide (BOX) disposed therebetween. The substrate may include one or more single crystal surfaces and / or one or more other surfaces, which may include non-single crystal surfaces, such as polycrystalline surfaces and / or amorphous surfaces. The substrate may include a layer including a metal (eg, copper, cobalt, etc.).

[0024] The term precursor and / or precursor gas may refer to a gas or combination of gases that participates in a chemical reaction that produces another compound. For example, a precursor gas may be used to grow an epitaxial layer comprising silicon carbide. The precursor gas may include a deposition gas, a doping gas, a carrier gas, or a combination of a deposition gas, a doping gas, or a carrier gas.

[0025] As described in more detail below, using an example gas injection system as described herein can eliminate adjustments for cross-substrate thickness variations and cross-substrate resistivity variations. Compared to conventional systems where the MCFs on the primary and secondary headers can have similar configurations or flow restriction structures, the gas injection system of the present disclosure employs unmatched MCFs. These unmatched MCFs can be configured to have different mass flow ranges and allow independent adjustment of the thickness distribution and resistivity distribution of the deposited material layer (e.g., epitaxially formed layer on the substrate).

[0026] In the following description of various embodiments, reference is made to the accompanying drawings, which form a part of the description, and in which various embodiments of various aspects of the present disclosure can be practiced are illustrated in the accompanying drawings. It should be understood that other embodiments can be utilized without departing from the scope of the present disclosure, and structural and functional modifications can be made. Various aspects of the present disclosure can have other embodiments and can be practiced or executed in various ways. In addition, it should be understood that the words and terms used here are for the purpose of description and should not be considered as restrictive. On the contrary, the phrases and terms used here will be given their broadest interpretation and meaning. The use of "include" and "comprise" and their variants means to include the items listed thereafter and their equivalents and additional items and their equivalents. Although various directional arrows are shown in the drawings of the present disclosure, the directional arrows are not intended to be limited to the extent of excluding two-way communication. On the contrary, the directional arrows are to show the general flow of steps, rather than the unidirectional movement of information. Throughout the specification, when an element is referred to as "including" or "comprising" another element, the element should not be understood to exclude other elements, as long as there is no special conflict description, and the element can include at least one other element. Throughout the specification, expressions such as “at least one of a, b, and c” may include “only a”, “only b”, “only c”, “a and b”, “a and c”, “b and c” and / or “all of a, b, and c”.

[0027] Figure 1An example of a reactor system is shown. The reactor system 100 can be used for various applications, such as chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), atomic layer deposition (ALD), cleaning processes, etching processes, etc. The reactor system 100 can include an optional substrate handling system 102, a reaction chamber 104, a gas injection system 106, and an optional wall 108 disposed between the reaction chamber 104 and the substrate handling system 102. The system 100 can also include a first gas source 112, a second gas source 114, and an exhaust source 110. Although two gas sources 112, 114 are shown, the reactor system 100 can include any suitable number of gas sources. The gas sources 112, 114 can include, for example, precursor gases such as trichlorosilane (TCS), dichlorosilane (DCS), silane, disilane, and trisilane; dopant sources such as gases containing As, P, C, Ge, and B; and carrier gases such as hydrogen, nitrogen, argon, helium, etc.

[0028] The reactor system 100 may include any suitable number of reaction chambers 104 and substrate processing systems 102. For example, the reaction chambers 104 of the reactor system 100 may include a cross-flow, cold-wall epitaxial reaction chamber, such as from an ASM system (e.g., ASM reactor system).

[0029] During operation of the reactor system 100, a substrate, such as a semiconductor wafer (not shown), is transferred from the substrate processing system 102 to the reaction chamber 104. Once the substrate is transferred to the reaction chamber 104, one or more gases, such as precursors, dopants, carrier gases, and / or purge gases, from the gas sources 112, 114 may be introduced into the reaction chamber 104 via the gas injection system 106. As described in more detail below, the gas injection system 106 may be used to meter and control the gas flow of one or more gases from the first gas source 112 and the second gas source 114 during substrate processing and provide the desired flow of such gases to the reaction chamber 104. Reference will be made to Figure 2 A more detailed description of the gas injection system is provided.

[0030] Figure 2A schematic diagram of an example of a gas injection system is shown. The gas injection system 200 may include a first gas supply line 202 coupled to a first gas source 203, which may be similar to the gas source 112; and a second gas supply line 204 coupled to a second gas source 205, which may be similar to the gas source 114. The gas injection system 200 may include a first gas manifold 206 (e.g., a primary manifold) coupled to the first gas supply line 202 and a second gas manifold 208 (e.g., an auxiliary manifold) coupled to the second gas supply line 204. The first gas manifold 206 may include a plurality of first gas outlets 210-218, and the second gas manifold 208 may include a plurality of second gas outlets 220-228. The first gas header 206 and the second gas header 208 may be configured to receive gas from one or more gas lines (e.g., the first and second gas lines 202, 204) and distribute the gas into one or more first channels and one or more second channels, which are defined in part by the first gas outlets 210-218 and the second gas outlets 220-228, respectively.

[0031] exist Figure 2 In the example of FIG. 1 , each of the first and second gas flows from the first gas source 203 and the second gas source 205 can be divided into five first channels and five second channels. Although the first gas header 206 and the second gas header 208 are illustrated as being connected to five channels, a gas injection system according to the present disclosure may include any suitable number of channels for the respective gases. For example, the first gas header 206 may be a main gas header connected to seven channels, and the second gas header 208 may be an auxiliary gas header connected to three channels.

[0032] The gas injection system 200 may include a flow controller 207-213 that controls the mass flow of the first gas source 203 and / or the second gas source. The gas injection system 200 may include a plurality of flow sensors 230-248 coupled to the first and second gas outlets 210-228. The flow sensors 230-248 may monitor the mass flow of the gas mixture and provide a user with real-time and / or historical flow information for each channel, which may be presented on a graphical user interface. Additionally and / or alternatively, the flow sensors 230-248 may be coupled to the main controller 215 and the gas valves 250-258 to provide a controlled flow ratio of the gas through the gas valves 250-268. The main controller 215 may control the function of the gas valves 250-268. The gas valves 250-268 may include any suitable device to meter the flow of the gas. The flow sensors 230-248 and the gas valves 250-268 may form a mass flow controller. For example, the flow meter 230 and the gas valve 250 can form or be part of a mass flow controller 270. Similarly, the flow sensors 232-248 and the gas valves 252-258 can form or be part of mass flow controllers 272-288. The master controller 215 can use mass flow controllers (MFCs) 270-288 to control the flow through the channels of the gas injection system 200. Each of the MFCs 270-288 can include a controller 225 within the dashed outline of the corresponding MFC, and each MFC can communicate with the master controller 215. Although Figure 2 Only MFC 270 is shown to include controller 225, but MFCs 270-288 can each include a controller similar to controller 225, and each controller in MFCs 270-288 can communicate with main controller 215. Operably, main controller 215 can provide mass flow targets to controllers 225 in each MFC 270-288. In turn, each controller 225 can throttle electromagnetic metering valves (e.g., electromagnetic metering valves 250-268) based on a comparison of the received mass flow target and the mass flow reported by the MFM (e.g., MFM 230-246). Main controller 215 can send different mass flow targets to each of the main MFC and auxiliary MFCs to adjust cross-substrate flow and cross-substrate material layer properties.

[0033] Figure 3 A block diagram of primary and secondary headers for decoupling adjustments for cross-substrate thickness variation and cross-substrate resistivity variation is shown. Figure 3 2 shows a view of an example gas injection system 300. The gas injection system 300 can show various gas sources flowing into the reaction chamber via a main header and an auxiliary header. Figure 3As shown, the gas injection system 300 may include a main manifold 310 (e.g., a main automatic gas injection (AGI)) and an auxiliary manifold 320 (e.g., an auxiliary AGI). The main manifold 310 may be a main manifold connected to an injection flange 360 ​​having a first set of injection ports (e.g., main injection ports), and the auxiliary manifold 320 may be an auxiliary manifold connected to an injection flange 360 ​​having a second set of injection ports (e.g., auxiliary injection ports). The main manifold may include a plurality of first mass flow controllers (MFCs) 340a. The auxiliary manifold may include a plurality of second MFCs 340b. Each first MFC 340a (e.g., a main MFC) may have a first flow restriction structure 350a, such as a control valve (e.g., a diaphragm valve) or an orifice plate. Each second MFC (e.g., an auxiliary MFC) 340b may have a second flow restriction structure 350b, such as a control valve (e.g., a diaphragm valve) or an orifice plate. These flow restriction structures may define different effective flow areas. Due to the differences in their flow restriction structures, the plurality of first MFCs may have a first mass flow range, and the plurality of second MFCs may have a second mass flow range.

[0034] exist Figure 3 In the example of , the main manifold 310 includes seven (7) mass flow controllers (e.g., main MFCs), which are respectively connected to seven main injection ports located on the injection flange 360. The auxiliary manifold 320 includes three (3) MFCs (e.g., auxiliary MFCs), which are respectively connected to three auxiliary injection ports located on the injection flange 360. Although seven MFCs on the main manifold and three MFCs on the auxiliary manifold are described, the main manifold can have any number of main MFCs and the auxiliary manifold can have any number of auxiliary MFCs. The three auxiliary injection ports can be distributed among the seven main injection ports. The main manifold 310 can be coupled to a precursor source, a dopant source, and a carrier source, and the auxiliary manifold 320 can be coupled to a dopant source and a carrier source. For example, a silicon precursor source (e.g., TCS), a dopant source (e.g., a main dopant (e.g., "P dopant")), and a carrier source (e.g., hydrogen (H2)) can flow to the main manifold 310 to provide silicon precursor and dopant to the reaction chamber through the main injection ports on the injection flange 360. The dopant source and carrier source may be further connected to the auxiliary header 320 to provide additional dopant (e.g., "A dopant") to the reaction chamber through the auxiliary injection port on the injection flange 360. During deposition, the silicon precursor flow and the first dopant (e.g., "P dopant") flow may be provided to the injection flange through the main header 310 and mixed with the second dopant (e.g., "A dopant") flow provided through the auxiliary header 320.

[0035] In a conventional system, precursors and dopants may be injected into a reaction chamber using a set of injector settings. For example, the mass flow ranges controlled by the MFCs on the main and auxiliary manifolds may be the same. The system typically first adjusts the thickness distribution by changing the injector settings, such as the mass flow rate on the main manifold, to obtain the desired thickness distribution. To adjust the resistivity distribution, the system may then change the injector settings, such as the mass flow rate on the auxiliary manifold, which in turn affects the thickness distribution. Similarly, if the injector settings are changed to adjust the thickness, these changes may also affect the resistivity distribution. In such a conventional system, the main manifold and the auxiliary manifold may have the same or similar configuration. For example, the mass flow ranges on both the main MFC and the auxiliary MFC may be set at around 55 SLM. Conventional systems may require a large amount of carrier gas (e.g., hydrogen (H2)) to flow into each auxiliary injection port to maintain a reasonable signal-to-noise ratio. When the mass flow range of the auxiliary injection port is comparable to that of the main injection port, such a conventional system may lack resolution and control over the auxiliary injection port and may not be able to decouple the adjustment of resistivity and thickness on the substrate. Therefore, conventional systems may not meet customer requirements for optimal resistivity and thickness distribution as well as minimal disturbance during adjustment.

[0036] Compared to conventional systems, in system 300, the main MFC and the auxiliary MFC can be individually set to control the mass flow range of each of the main MFC and the auxiliary MFC. The main MFC and the auxiliary MFC can have an unmatched configuration so that the second mass flow range of the auxiliary MFC can be significantly lower than the first mass flow range of the main MFC. In some examples, the value in the second mass flow range can be between about 1% and about 10% of the value in the first mass flow range. For example, the value in the second mass flow range can be about 1% to about 2% of the value in the first mass flow range, or about 2% to about 4% of the value in the first mass flow range, or about 4% to about 6% of the value in the first mass flow range, or about 6% to about 8% of the value in the first mass flow range. Limiting the mass flow through the auxiliary manifold to these ranges can decouple the adjustment of the resistivity of the auxiliary MFC from the uniformity of the thickness across the substrate. Decoupling the resistivity adjustment from the thickness variation across the substrate material layer will in turn limit the need for cross-substrate resistivity adjustment (e.g., cross-substrate resistivity uniformity) and cross-substrate material layer thickness adjustment (e.g., cross-substrate material layer thickness uniformity).

[0037] In some examples of system 300, the first mass flow range does not overlap with the second mass flow range. In some examples, the first mass flow range of the main MFC is about 30 to about 110 standard liters per minute (SLM), such as between about 30SLM and about 40SLM, or between about 40SLM and about 50SLM, or between about 50SLM and about 60SLM, or between about 60SLM and about 70SLM, or between about 70SLM and about 80SLM, or between about 80SLM and about 90SLM, or between about 90SLM and about 100SLM, or between about 100SLM and about 110SLM. The flow rate within these ranges can enable the deposition rate of the silicon-containing epitaxial material layer to provide an acceptable yield, thereby optimizing the cost of ownership. The second mass flow range of the auxiliary MFC is about 1 to about 7SLM, such as between about 1SLM and about 3SLM, or between about 3SLM and about 5SLM, or between about 5SLM and about 7SLM. Flow rates within these ranges may enable doping of a silicon-containing epitaxial material layer deposited at a deposition rate that provides acceptable throughput, wherein the level of dopant provides acceptable surface resistivity for semiconductor devices.

[0038] In some examples of system 300, the main MFC and the auxiliary MFC may have different flow restriction structures, which at least partially determine the difference in their mass flow ranges. In some examples, each of the main MFC and the auxiliary MFC may include a flow metering value, which includes an inlet port, a control valve (e.g., a diaphragm valve), and an outlet port. The control valve in the first position can couple the inlet port fluid to the outlet port. The control valve in the second position can decouple the inlet port from the outlet port fluid. The inlet port, control valve, and outlet port in each main MFC can form a first mass flow restriction structure, which limits the mass flow of gas within a first mass flow range. The inlet port, control valve, and outlet port in each auxiliary MFC can form a second mass flow restriction structure with a second effective flow area, which limits the mass flow of gas within a second mass flow range. The first and second mass flow restriction structures may include different inlet port cross-sections, different outlet port cross-sections, different inlet port diameters, different diaphragm to valve seat spacings, different outlet port diameters, or different inlet port holes, output port holes, or different orifice plates with different effective flow areas. For example, the inlet port in the flow metering valve included in the auxiliary MFC may have a smaller diameter or cross-section, resulting in a smaller effective flow area than the inlet port in the flow metering valve included in the main MFC having a larger diameter or cross-section. The difference in flow restriction structure can provide different accuracy when metering the flow of the main MFC and the auxiliary MFC. The details of these flow restriction structures will be described in Figures 7A-7C Further discussion in.

[0039] For example, the main MFC 340a of the main manifold 310 may have an orifice plate 350a. The auxiliary MFC 340b of the auxiliary manifold 320 may have an orifice plate 350b. The orifice plate 350a may have a larger hole opening than the orifice plate 350b. In another example, the main MFC and the auxiliary MFC may have different restrictors. In yet another example, the main MFC and the auxiliary MFC may have different inlet ports and / or outlet ports on the valves in the corresponding MFCs. Due to these differences in flow restriction structures, a plurality of main MFCs may have a first effective flow area, and a plurality of auxiliary MFCs may have a second effective flow area, wherein the second effective flow area may be smaller than the first effective flow area. In some examples of the system 300, each main MFC may include a first sensor configured to measure a first gas flow rate within a first mass flow range, and each auxiliary MFC may include a second sensor configured to measure a second gas flow rate within a second mass flow range, and the second sensor may have a higher sensitivity than the first sensor. For example, the sensor and gas valve in the auxiliary MFC may be suitable for monitoring and metering a relatively low mass flow range of the gas flow through the auxiliary injection port. In system 300, a relatively small amount of carrier gas (e.g., hydrogen (H2)) may flow into each of the three auxiliary injection ports compared to a relatively large amount of carrier gas (e.g., hydrogen (H2)) flowing into each of the seven main injection ports. Such auxiliary MFCs with higher sensitivity may provide resolution and more precise control of the auxiliary injection ports with a relatively lower mass flow range, which may provide the ability to adjust the resistivity distribution independently of the thickness distribution across the substrate 330. For example, the controller ( Figure 3 The controller (not shown) can control the deposition of a material layer on a substrate (e.g., wafer 330) by controlling a plurality of main MFCs and a plurality of auxiliary MFCs. The controller can adjust the cross-substrate thickness variation of the material layer by controlling the plurality of main MFCs. The controller can adjust the cross-substrate resistivity variation of the material layer by controlling the plurality of auxiliary MFCs and independently of the cross-substrate thickness variation. The mass flow ratio between the three auxiliary MFCs can be further controlled and adjusted to achieve a more uniform profile at the pyrolysis center and the pyrolysis edge of the substrate 330. For example, the controller can adjust the distribution of the carrier flow through the plurality of auxiliary injection ports to the deposition chamber through the plurality of auxiliary MFCs to adjust the cross-substrate resistivity variation of the material layer. The controller can adjust the distribution of the dopant flow between the plurality of main injection ports coupled to the main manifold and the plurality of auxiliary injection ports coupled to the auxiliary manifold through the plurality of auxiliary MFCs to adjust the cross-substrate resistivity variation of the material layer.

[0040] Compared to conventional systems with uniform injector settings on the MFC, the system 300 may have mismatched main MFCs and auxiliary MFCs. The main MFC can implement lateral flow adjustment (i.e., lateral flow adjustment) so that any one of the main MFCs provides a flow rate different from another of the first plurality of MFCs, for example, between about 5% and about 20% of the total flow rate from the main manifold. This total flow range can enable other factors that drive thickness variations across the substrate material layer (e.g., heating non-uniformity) to be compensated by lateral variations in the precursor flow rate at the injection manifold. Similarly, the auxiliary MFC can implement lateral flow adjustment (i.e., lateral flow adjustment) so that any one auxiliary MFC can provide a flow rate different from another auxiliary MFC, for example, between about 20% and about 50% of the total flow rate from the auxiliary manifold. This total flow range can enable other factors that drive resistivity across the substrate material layer (e.g., lateral variations in the precursor flow rate from the main manifold) to be compensated by lateral variations in the precursor flow rate at the injection manifold.

[0041] Figures 4A-4C An example graph illustrating adjustment of thickness profile and resistivity profile according to one or more aspects of the present disclosure is shown. The flow rate of the auxiliary header can be reduced relative to the flow rate of the main header, so as to have less dilution effect and interference with the adjustment of the thickness profile. Several tests have been conducted to explore the optimal flow range of the auxiliary header relative to the main AGI.

[0042] exist Figure 4A In the embodiment, a carrier gas (e.g., hydrogen (H2)) is introduced into the reaction chamber via three auxiliary injection ports at a flow rate of 10 SLM, while the flow rate of the main injection port can be maintained at about 60 SLM. Figure 4A The thickness distribution on the left side, graphs 402, 404 and 406 represent the thickness distribution shown in FIG. Figure 4AResistivity distribution on the right. For example, the resistivity distribution is tested in three cases: 1) a graph 402 corresponding to the carrier gas flow ratios allocated as A1%, A2%, and A3% in the three auxiliary MFCs; 2) a graph 404 corresponding to the carrier gas flow ratios allocated as B1%, B2%, and B3% in the three auxiliary MFCs; and 3) a graph 406 corresponding to the carrier gas flow ratios allocated as C1%, C2%, and C3% in the three auxiliary MFCs. A1, A2, A3, B1, B2, B3, C1, C2, and C3 can range from 0% to 100%. For example, A1, A2, and A3 can constitute 100% of the total carrier gas flow on the auxiliary header. Likewise, the thickness distribution was tested under similar circumstances: 1) a graph 412 corresponding to the carrier gas flow ratios allocated as A1%, A2% and A3% in three auxiliary MFCs; 2) a graph 414 corresponding to the carrier gas flow ratios allocated as B1%, B2% and B3% in three auxiliary MFCs; and 3) a graph 416 corresponding to the carrier gas flow ratios allocated as C1%, C2% and C3% in three auxiliary MFCs.

[0043] In such Figure 4A In the case where the flow rate on the auxiliary manifold is shown to be 10 SLM (e.g., the mass flow rate of the auxiliary manifold is low compared to the mass flow rate of the main manifold (e.g., 60 SLM), changing the flow rate of the carrier gas to adjust the resistivity distribution may result in a drastic change in the thickness distribution. For example, switching from curve 402 to curve 406 in the resistivity distribution results in a corresponding change in the thickness distribution from curve 412 to curve 416. This shows that when the mass flow rate of the carrier gas associated with the auxiliary injection port (i.e., the auxiliary manifold carrier gas) is 10 SLM, adjusting the resistivity distribution is closely related to the thickness distribution. At 10 SLM, Figure 4A A strong coupling effect between thickness and resistivity, as well as low resistivity tunability, is shown.

[0044] exist Figure 4B In the auxiliary manifold, the mass flow rate of the carrier gas can be further reduced to 2SLM. Figure 4B In the embodiment, a carrier gas such as hydrogen (H2) is introduced into the reaction chamber through three auxiliary injection ports at a mass flow rate of 2 SLM, while the mass flow rate of the main injection port is maintained at about 60 SLM. Three curve graphs 421, 423 and 425 representing the thickness distribution are shown in FIG. Figure 4B On the left side of FIG. 4 , three graphs 422, 424 and 426 representing resistivity distribution are shown. Figure 4BFor example, the resistivity distribution is tested in three cases: 1) a graph 422 corresponding to the carrier gas flow ratios allocated as A1%, A2%, and A3% in the three auxiliary MFCs; 2) a graph 424 corresponding to the carrier gas flow ratios allocated as B1%, B2%, and B3% in the three auxiliary MFCs; and 3) a graph 426 corresponding to the carrier gas flow ratios allocated as C1%, C2%, and C3% in the three auxiliary MFCs. Similarly, the thickness distribution is tested in these similar scenarios. Figure 4B As shown, when the flow rate on the auxiliary manifold is 2 SLM (e.g., the mass flow rate of the auxiliary manifold is much lower than the mass flow rate of the main manifold (e.g., 60 SLM), changing the flow rate ratio of the carrier gas on the resistivity distribution still causes some changes in the thickness distribution. However, the three thickness distributions 421, 423, and 425 begin to converge, which is consistent with Figure 4A (where the mass flow rate of the carrier gas on the auxiliary manifold is 10SLM), the effect on the thickness distribution is significantly smaller. This shows that when the mass flow rate of the carrier gas on the auxiliary manifold is 2SLM, the correlation between the adjusted resistivity distribution and the thickness distribution is reduced. At 2SLM, Figure 4B Significantly reduced coupling effect between thickness and resistivity, as well as sufficient resistivity tunability, are demonstrated.

[0045] exist Figure 4C In the figure, the flow rate of the auxiliary manifold carrier gas can be further reduced to 1 SLM, showing the decoupling of thickness and resistivity. Figure 4C In FIG. 4 , carrier gas H2 is introduced into the reaction chamber through three auxiliary injection ports at a mass flow rate of 1 SLM, while the mass flow rate of the main injection port is maintained at about 60 SLM. Three curve graphs 431, 433, and 435 representing the thickness distribution are shown in FIG. Figure 4C On the left side of FIG. 4 , three graphs 432, 434 and 436 representing resistivity distribution are shown. Figure 4C For example, the resistivity distribution is tested in three cases: 1) a graph 432 corresponding to the carrier gas flow ratios allocated as A1%, A2%, and A3% in the three auxiliary MFCs; 2) a graph 434 corresponding to the carrier gas flow ratios allocated as B1%, B2%, and B3% in the three auxiliary MFCs; and 3) a graph 436 corresponding to the carrier gas flow ratios allocated as C1%, C2%, and C3% in the three auxiliary MFCs. Similarly, the thickness distribution is tested in these similar scenarios. Figure 4CAt a mass flow rate of 1 SLM on the auxiliary manifold shown (e.g., the mass flow rate of the auxiliary manifold is extremely low compared to the mass flow rate of the main manifold (e.g., 60 SLM), changing the flow ratio of the carrier gas on the resistivity distribution can result in minimal changes in the thickness distribution, and the three thickness distributions 431, 433, and 435 have basically converged. This shows that when the mass flow rate of the auxiliary manifold carrier gas is 1 SLM, adjusting the resistivity distribution can be decoupled from the thickness distribution. At 1 SLM, Figure 4C Negligible coupling effects between thickness and resistivity, as well as fuller resistivity tunability, are shown.

[0046] One goal of adjusting the resistivity profile may be to increase the uniformity of the resistivity profile so that high to low variations can be minimized. This goal may not be achievable in conventional systems because by changing the injector settings, both the thickness and resistivity will change accordingly. By using a substantially smaller mass flow range on the auxiliary manifold, the resistivity profile can be adjusted by adjusting the flow rates on the three auxiliary MFCs independently of the adjustment of the thickness profile. The resistivity profile can be adjusted to be relatively flat to obtain a more uniform resistivity profile, while the adjustment process causes no or minimal disturbance to the thickness profile.

[0047] The uniformity of resistivity distribution can be reflected in Figure 4C The flatness of the resistivity curve in the x-axis shows the distance from the center of the substrate in the diameter scan. For example, the left end of the x-axis represents the left edge of the substrate, 0 represents the center of the substrate, and the right end of the x-axis represents the right edge of the substrate. Figure 4C Of the three resistivity graphs, graph 434 provides better uniformity because the resistivity remains relatively flat across the substrate. Graph 434 corresponds to flow ratios of B1%, B2%, and B3% distributed among the three auxiliary MFCs. The flow ratios can be adjusted to achieve improved uniformity in the resistivity distribution without much impact on the thickness distribution. In this way, the system can be adjusted to identify the optimal flow ratio on the auxiliary MFCs that not only decouples the thickness and resistivity distributions, but also increases substrate-to-substrate stability. Based on Figures 4A-4C For the test scenario shown, the gas injection system can be adapted to reduce the flow rate on the auxiliary MFC to achieve a mechanism that decouples the adjustment of thickness and resistivity distribution.

[0048] like Figures 4A to 4CAs shown, reducing the flow rate of the carrier gas on the auxiliary manifold can reduce the dilution and interference with the main AGI. If the flow rate of the main manifold is set to 60SLM and the flow rate of the auxiliary manifold carrier gas is set to 10SLM, the flow ratio of the main manifold to the auxiliary manifold is 6:1, and there may still be interference between the thickness and resistivity adjustments. If the main manifold is maintained at the same flow rate of 60SLM and the auxiliary manifold is set at 1SLM, the flow ratio of the main manifold to the auxiliary manifold is 60:1, and there is no interference or minimal interference between the thickness and resistivity adjustments. In this case, the auxiliary manifold may not have much dilution effect on the main manifold, and the thickness distribution can be adjusted first by changing the injector settings on the main manifold (e.g., seven MFC mass flow rates) to obtain the desired thickness distribution. The resistivity distribution can then be adjusted by adjusting the injector settings on the auxiliary manifold (e.g., three MFC mass flow rates). Reducing the mass flow rate of the carrier gas on the auxiliary manifold can minimize the interference effect on the thickness, and the thickness has been adjusted to the desired thickness distribution. In this way, the thickness distribution can be decoupled from the resistivity distribution, and the crosstalk between the thickness and resistivity adjustments can be eliminated.

[0049] exist Figures 4A to 4C In the example of , there are three auxiliary injection ports (e.g., Auxiliary 1, Auxiliary 2, and Auxiliary 3) in the gas injection system, and their mass flow rates can be controlled by corresponding auxiliary MCFs. Conventional systems can use auxiliary manifold settings similar to the main manifold settings. For example, in a conventional system, the mass flow rate of the auxiliary manifold can be set to 55SLM, which is the same or similar to the mass flow rate on the main manifold. The auxiliary MCF, including the flow sensor and the gas valve, may have a similar configuration to the main MCF. In the examples of 4A to 4C, the controller may be suitable for achieving a much smaller mass flow rate on the auxiliary manifold. The auxiliary MCF may be suitable for monitoring and metering a much smaller mass flow range, such as about 1SLM to about 7SLM. Auxiliary 1-3 may have a flow limiting structure suitable for measuring a much lower mass flow range. Such a system (e.g., system 300) can be used to adjust the thickness distribution of a material layer deposited on a substrate by changing the settings on the main manifold to achieve a desired thickness distribution.

[0050] This system can be used to further adjust the resistivity distribution of the material layer deposited on the substrate. Although it is possible to have the same flow rate on each auxiliary 1-3, it is also possible to have different mass flow rates and distributions on each auxiliary 1-3. For example, the flow ratio can be set to Auxiliary 1 A1%, Auxiliary 2 A2%, and Auxiliary 3 A3%. Assuming that the mass flow rate of the auxiliary pipe is set to be much smaller than the mass flow rate of the main pipe, adjusting the flow ratio of Auxiliary 1-3 will change the resistivity distribution, but may not affect the thickness distribution much.

[0051] Figure 5An example flow chart describing a process for decoupling thickness and resistivity adjustments in a gas injection system is shown. In step 510, the gas injection system can deposit a material layer on a substrate by controlling a plurality of first mass flow controllers (MFCs) and a plurality of second MFCs. A controller in the gas injection system can configure one or more first MFCs (e.g., main MFCs) and a plurality of second MFCs (e.g., auxiliary MFCs). The gas injection system can include a main manifold (e.g., a main manifold) including a plurality of first MFCs. The controller can configure the plurality of first MFCs to have a first mass flow range. The main manifold can be coupled to a precursor source, a dopant source, and a carrier source.

[0052] The controller may configure a plurality of second MFCs. The gas injection system may include an auxiliary header (e.g., an auxiliary manifold) containing a plurality of second MFCs. The controller may configure the plurality of second MFCs to have a second mass flow range. The second mass flow range may be different from the first mass flow range. In some examples, the first mass flow range may not overlap with the second mass flow range. The auxiliary header may be coupled to a dopant source and a carrier source.

[0053] In operation, the carrier source may include one or more tanks containing a carrier selected from nitrogen, hydrogen and helium. The precursor source may include one or more tanks containing a precursor selected from trichlorosilane, dichlorosilane, silane, disilane, trisilane and silicon tetrachloride. The dopant source may include one or more tanks containing a dopant selected from germane, diborane, phosphine, arsine and phosphorus trichloride. The controller may be coupled in communication with the plurality of first MFCs and the plurality of second MFCs to control the operation of the MFCs.

[0054] The gas injection system may also include an injection flange having a plurality of main injection ports and a plurality of auxiliary injection ports. The plurality of first MFCs may be configured to control a first flow of precursors, dopants, and carriers to the deposition chamber through the plurality of main injection ports. The plurality of second MFCs may be configured to control a second flow of dopants and carriers to the deposition chamber through the plurality of auxiliary injection ports. Through the operation of the plurality of first MFCs and the second MFCs, the gas injection system may control the deposition of a material layer on a substrate.

[0055] In some examples, the gas injection system may include seven first MFCs (e.g., main MFCs) and three second MFCs (e.g., auxiliary MFCs). The gas injection system may have different numbers of main MFCs and auxiliary MFCs. The main MFC and the auxiliary MFC may have different flow restriction structures and configurations, suitable for monitoring and metering different mass flow ranges. For example, a plurality of main MFCs may be configured to monitor and meter a first mass flow range, while a plurality of auxiliary MFCs may be configured to monitor and meter a second mass flow range. In some examples, the value in the second mass flow range may be between about 1% and about 10% of the value in the first mass flow range. A plurality of main MFCs may define a first effective flow area, and a plurality of auxiliary MFCs may define a second effective flow area. The second effective flow area may be significantly smaller than the first effective flow area. When the main MFC is fully opened, the first effective flow area may control the flow through the main MFC. When the second MFC is fully opened, the second effective flow area may control the flow through the second MFC. The effective flow area may be defined by one or more of a conduit, an orifice plate, and / or a restrictor. The conduit may include an inlet port and / or an outlet port on a valve within the corresponding MFC. For example, each primary MFC may have a larger orifice plate than the auxiliary MFCs.

[0056] The MFC may include a pressure transient insensitive (PTI) mass flow controller that can minimize process gas flow variations due to pressure and temperature fluctuations. The MFC may include a flow sensor for monitoring the mass flow of the gas mixture and providing real-time and / or historical mass flow information to a user. The flow sensor may be communicatively coupled to a controller, such as Figure 6 The controller may receive data from a flow sensor monitoring mass flow and send instructions to the gas valve to control and adjust the mass flow. The flow sensor may be connected to the gas valve to provide a controlled flow rate of gas through the gas valve. In some examples, the flow sensor may include a thermal mass flow sensor or a pressure drop based flow sensor.

[0057] In step 520, the controller may adjust the cross-substrate thickness variation of the material layer by controlling the plurality of first MFCs. For example, the controller may determine a first mass flow rate of a carrier source associated with the plurality of first MFCs. The first MFCs may be coupled to a first plurality of flow sensors. The first flow sensors may monitor parameters of each first MFC, such as a mass flow rate of a carrier gas source, such as hydrogen (H2). The first flow sensors may send sensor data including a mass flow rate to the controller. The controller may receive sensor data from the first flow sensors and monitor the mass flow rate of the first MFCs.

[0058] The controller can control multiple first MFCs to adjust the cross-substrate thickness variation of the material layer. Furthermore, multiple first MFCs can measure and control the first flow of precursors, dopants and carriers to the deposition chamber through multiple main injection ports. The thickness variation of the material layer can be adjusted by changing the mass flow rate of the first MFC. The thickness variation of the material layer can be further adjusted by changing the distribution of the gas flow to the deposition chamber through multiple main injection ports. For example, the thickness variation can be adjusted by adjusting the distribution of the carrier flow in the seven main MFCs.

[0059] At step 530, the controller may determine whether the desired cross-substrate thickness variation has been achieved. If the desired cross-substrate thickness variation has been achieved, the process proceeds to step 540; otherwise, the process returns to step 520 to continue adjusting the cross-substrate thickness variation by controlling the first MFC.

[0060] In step 540, the controller can adjust the cross-substrate resistivity variation of the material layer independently of the cross-substrate thickness variation and by controlling multiple second MFCs. The second MFCs can be coupled to a second flow sensor. The second flow sensor can monitor a parameter, such as a second mass flow rate of a dopant source or a carrier source (e.g., H2) on each second MFC. The flow sensor can send sensor data including the mass flow rate to the controller. The controller can receive the sensor data from the second flow sensor and monitor the second mass flow rate on the second MFC.

[0061] The controller can control the plurality of second MFCs to adjust the cross-substrate resistivity variation of the material layer. In turn, the plurality of second MFCs can meter and control the second flow of dopants and carriers to the deposition chamber through the plurality of auxiliary injection ports. The second MFCs can be coupled to a plurality of gas valves that can be adjusted to change the effective flow area of ​​the second MFCs. Thus, the second mass flow rate of the second MFC can be adjusted, which can adjust the cross-substrate resistivity variation of the material layer.

[0062] The controller can control the second mass flow rate of the second MFC to adjust the resistivity distribution of the deposited material layer independently of the thickness distribution of the deposited material layer. The controller can initially adjust the first mass flow rate to adjust the thickness distribution of the deposited material layer independently of the resistivity distribution. For example, as discussed in steps 520-530, the controller can adjust the first mass flow rate of the first MFC, and the desired thickness distribution can be achieved. The controller can adjust the second mass flow rate to adjust the resistivity distribution. For example, the controller can adjust a second plurality of gas valves to change the second mass flow rate, and the second plurality of gas valves can be coupled to the second MCF. For example, if the first mass flow rate is about 30 to about 110 SLM, the second flow rate can be adjusted to about 1 to about 7 SLM, indicating that the second mass flow rate range can be significantly lower than the first mass flow rate range. An optimal ratio between the first and second mass flow rates can be selected to minimize crosstalk between thickness and resistivity while maintaining the stability of the flow of dopants or carriers through the auxiliary manifold.

[0063] After adjusting the second mass flow rate to be significantly lower than the first mass flow rate, changing the second mass flow rate can have minimal impact on the thickness distribution. The controller can adjust the second mass flow rate to obtain a desired resistivity distribution independent of the thickness distribution. For example, the first mass flow rate can be adjusted to about 55 SLM to achieve an optimal thickness distribution, and the second mass flow rate can be adjusted to about 1 SLM to achieve an optimal resistivity distribution.

[0064] Adjusting the resistivity distribution may include adjusting the distribution of carrier sources to the deposition chamber through multiple auxiliary injection ports. Each second MFC on the auxiliary manifold can contribute a portion of the total flow of the auxiliary manifold (e.g., 3SLM), and the adjustment of any one second MFC can change a portion of the total flow of the auxiliary manifold passing through each second MFC. After the auxiliary manifold flow is set to an optimal range or value (e.g., 3SLM), the resistivity distribution can be adjusted by adjusting the distribution of the total flow on the three auxiliary MFCs. For example, under condition 1, the flow ratio between the three auxiliary manifold MFCs can initially be distributed as 33%, 33%, and 33%. Under condition 2, the flow ratio between the three auxiliary manifold MFCs can be distributed as 25%, 50%, and 25%, respectively. The controller can compare the resistivity distribution under these conditions and determine that, for example, condition 2 produces better uniformity in the resistivity distribution.

[0065] Adjusting the resistivity distribution can include adjusting the distribution of dopant sources carried by multiple main injection ports on the main header and multiple auxiliary injection ports on the auxiliary header. In one example, the amount of P dopant (carried on the main header) and A dopant (carried on the auxiliary header) can be approximately equal. In another example, the A dopant can be set to 80%, the P dopant can be set to 20%, and the ratio of the dopant source carried by the second header (e.g., the auxiliary header) to the dopant source carried by the first header (e.g., the main header) is 1 to 4.

[0066] At step 550, the controller may determine whether the desired cross-substrate resistivity variation has been achieved. If the desired cross-substrate resistivity has not been achieved, the process returns to step 540 to continue adjusting the cross-substrate resistivity variation through control or the second MFC. Otherwise, the process terminates. Although steps 520-550 have been Figure 5 , but these steps can be performed in parallel or in any order. For example, steps 520 and 540 can be performed in parallel so that the cross-substrate thickness variation and the cross-substrate resistivity variation can be adjusted simultaneously. It is also possible to perform step 540 before step 520. Steps 530 and 550 can also be performed in parallel or in any order (for example, step 530 is performed before step 550, or step 550 is performed before step 530).

[0067] Figure 6 An example of a computing device that can be used to implement one or more aspects of the present disclosure is depicted. The computing device can be a device used to control a system (e.g., 100, 200, 300) and perform a process (e.g., 500) described herein. For example, one or more devices and components (e.g., a controller) described herein can be used Figure 6 The device shown is implemented.

[0068] The term "network" as used herein and described in the accompanying drawings refers not only to a system in which remote storage devices are coupled together through one or more communication paths, but also to independent devices that can sometimes be coupled to such a system having storage capabilities. According to one or more illustrative aspects described herein, an example system architecture 600 can be used. The system 600 can have a processor 601 for controlling the overall operation of the system and its related components, including a read-only memory (ROM) 602, a random access memory (RAM) 603, a removable media 604, a hard drive 605, a display device 606, a device controller 607, an input device 608, a network input / output (I / O) device 609, and a speaker 611.

[0069] Input devices 608 may include a mouse, keyboard, touch screen, scanner, optical reader, and / or stylus (or other input devices) through which a user of system 600 can provide input. One or more speakers 611 may provide audio output, and display device 606 may provide text, audiovisual, and / or graphical output. Software may be stored in removable media 604 and / or hard drive 605 to provide instructions to processor 601 for configuring system 600 as a dedicated computing device to perform the various functions described herein. For example, removable media 604 and / or hard drive 605 may store software used by system 600, such as an operating system, application programs, and / or related databases.

[0070] The system 600 can operate in a network environment that supports connection to one or more remote computers or components (e.g., flow sensors 230-248, gas valves 250-268, etc.). The external network 610 can include a local area network (LAN) and a wide area network (WAN), but can also include other networks. When used in a LAN network environment, the system 600 can be connected to the LAN via a network I / O 609 (e.g., a network interface or adapter). When used in a WAN network environment, the system 600 can include a modem or other wide area network interface for establishing communication through a WAN such as the Internet. It will be understood that the network connection shown is illustrative and other means of establishing a communication link between computers can be used. The system 600 can be a mobile terminal (e.g., a mobile phone, a smart phone, a personal digital assistant (PDA), a laptop computer, etc.), including various other components, such as a battery, a speaker, and an antenna (not shown).

[0071] Fig. 7A An example mass flow metering valve of a mass flow controller (MFC) according to one or more aspects of the present disclosure is shown. Fig. 7A As shown, system 700 includes a controller 701, a mass flow meter 703, a diaphragm valve (or other type of control) 704, a solenoid 705, a precursor inlet port 707, and a precursor outlet port 708. In some examples, the main MFC and the auxiliary MFC may include a flow restriction structure, such as a flow metering valve. Specifically, the flow metering valve may include a diaphragm valve 704, which is coupled to the solenoid 705 and supported on a valve seat (e.g., Figure 7B), above the valve seat 710 shown in ), the inlet port 707 and the outlet port 708. The inlet port 704, the diaphragm (or other type) valve 704 and the outlet port 708 in the main MFC can form a first mass flow restriction structure, which limits the mass flow of the gas within a first mass flow range. The inlet port 704, the diaphragm (or other type) valve 704 and the outlet port 708 in the auxiliary MFC can form a second mass flow restriction structure, which limits the mass flow of the gas within a second mass flow range.

[0072] Figure 7B and 7C A top view and a side view of an example diaphragm seat of an MFC according to one or more aspects of the present disclosure are shown, including example effective flow areas of a main MFC and an auxiliary MFC. In this example, a valve 720 may include a bowl 711 having an inlet port 707 and an outlet port 708, through which a gas mixture may enter and leave the valve, respectively. The main MFC and the auxiliary MFC may have different effective flow areas through the valve. In one example, the auxiliary MFC may have an inlet port (marked 707A, indicated by a dotted line) of a smaller diameter, resulting in a smaller effective flow area than a main MFC (marked 707B) having a larger diameter. The valve may also include a valve seat 710, which extends around the inlet port and separates the outlet port from the inlet port.

[0073] System 720 may include solenoid 705 and diaphragm 704 ( Figure 7B 708). The solenoid 705 can act as a transducer device that converts energy into linear motion to move the diaphragm 704. For example, the solenoid 705 can be coupled to a controller that controls the movement of the diaphragm 704. The diaphragm 704 can move between a first position (shown as a solid line) and a second position (shown as a dashed line). In the first position, the diaphragm 704 is spaced apart from the valve seat 710 so that the inlet port 707 is fluidly coupled to the outlet port 708 (indicated by the arrow line extending from the inlet port 707 to the outlet port 708). In the first position, gas is allowed to flow from the inlet port 707 through the valve seat 710 to the outlet port 708. In the second position, the diaphragm 704 abuts the valve seat 710 and separates the inlet port 707 from the outlet port 708 (e.g., fluidly decouples) so that the flow of gas from the inlet port 707 through the valve seat 710 to the outlet port 708 is inhibited.

[0074] The auxiliary MFC and the main MFC may differ in other flow restriction structures, including different inlet port cross sections or holes, different outlet port cross sections or holes, different inlet port diameters, different diaphragms to valve seat spacings, different outlet port diameters or different orifice plates with different effective flow areas. These differences in flow restriction structures may correspond to different precisions of flow measurement on the main MFC and the auxiliary MFC. For example, the auxiliary MFC may have higher precision than the main MFC in metering flow. Since the inlet port 707 is close to the diaphragm 704, when the flow restriction device (e.g., solenoid 705) can be separated from the diaphragm 704 fluid, the hysteresis or hysteresis effect during the flow can be limited relative to conventional systems.

[0075] Although the subject matter has been described in language specific to structural features and / or methodological acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A gas injection system, comprising: a main manifold including a first plurality of mass flow controllers (MFCs) having a first mass flow range, wherein the main manifold is coupled to the precursor source, the dopant source, and the carrier source; an auxiliary manifold including a second plurality of MFCs having a second mass flow range, wherein the second mass flow range is different than the first mass flow range, and wherein the auxiliary manifold is coupled to a dopant source and a carrier source; and A controller comprising one or more processors and a memory storing computer readable instructions, which, when executed by the one or more processors, cause the controller to: depositing a material layer on a substrate by controlling a plurality of first MFCs and a plurality of second MFCs; adjusting a cross-substrate thickness variation of the material layer by controlling the plurality of first MFCs; and The cross-substrate resistivity variation of the material layer is adjusted by controlling the plurality of second MFCs and independently of the cross-substrate thickness variation.

2. The gas injection system according to claim 1, wherein: The values ​​in the second mass flow rate range are between about 1% and about 10% of the values ​​in the first mass flow rate range.

3. The gas injection system according to claim 1, wherein: The first mass flow range does not overlap with the second mass flow range.

4. The gas injection system according to claim 1, in, Each of the plurality of first MFCs and each of the plurality of second MFCs comprises an inlet port, a control valve, and an outlet port; wherein the control valve in the first position fluidly couples the inlet port to the outlet port; and Therein, the control valve in the second position fluidly decouples the inlet port from the outlet port.

5. The gas injection system according to claim 4, wherein: The control valve includes a valve seat and a solenoid-actuated movable diaphragm, wherein in a first position the diaphragm is spaced apart from the valve seat such that gas can flow from the inlet port through the valve seat to the outlet port, and in a second position the diaphragm abuts the valve seat such that gas flow from the inlet port through the valve seat to the outlet port is inhibited.

6. The gas injection system according to claim 4, wherein: The inlet port includes an orifice having an effective flow area that restricts mass flow of gas from the inlet port through the control valve to the outlet port when the control valve is in the first position.

7. The gas injection system of claim 6, wherein: An effective flow area of ​​the holes in each of the first plurality of MFCs is greater than an effective flow area of ​​the holes in each of the second plurality of MFCs.

8. The gas injection system according to claim 6, wherein: An effective flow area in each of the plurality of first MFCs limits mass flow rate within the first mass flow rate range, and an effective flow area in each of the plurality of second MFCs limits mass flow rate within the second mass flow rate range.

9. The gas injection system of claim 4, wherein: the inlet port, the control valve, and the outlet port in each of the plurality of first MFCs form a first mass flow restriction structure that restricts the mass flow of the first gas to within the first mass flow range; and The inlet port, the control valve and the outlet port in each of the plurality of second MFCs form a second mass flow restriction structure that restricts the mass flow of the second gas within the second mass flow range.

10. The gas injection system of claim 9, wherein: The first and second mass flow restriction structures include different inlet port cross-sections, different outlet port cross-sections, different inlet port diameters, different diaphragm-to-seat spacings, different outlet port diameters, or different orifice plates with different effective flow areas.

11. The gas injection system of claim 1, wherein: Each of the plurality of first MFCs includes a first sensor configured to measure a first gas flow rate within the first mass flow rate range, and each of the plurality of second MFCs includes a second sensor configured to measure a second gas flow rate within the second mass flow rate range, and wherein the second sensor has a higher sensitivity than the first sensor.

12. The gas injection system of claim 1, wherein: The first mass flow rate ranges from about 30 to about 110 standard liters per minute (SLM), and the second mass flow rate ranges from about 1 to about 7 SLM.

13. The gas injection system of claim 1, wherein: The first plurality of MFCs includes seven MFCs, and the second plurality of MFCs includes three MFCs.

14. The gas injection system of claim 1, further comprising: The injection flange comprises: a plurality of main injection ports corresponding one-to-one to the plurality of first MFCs, and a plurality of auxiliary injection ports corresponding one-to-one to the plurality of second MFCs, wherein the plurality of first MFCs are configured to control a first flow of precursors, dopants, and carriers to the deposition chamber through the plurality of main injection ports, The plurality of second MFCs are configured to control a second flow of dopants and carriers to the deposition chamber through the plurality of auxiliary injection ports.

15. The gas injection system of claim 14, wherein: When executed by the one or more processors, the computer readable instructions further cause the controller to: The distribution of carrier flow through the plurality of auxiliary injection ports to the deposition chamber is adjusted by the plurality of second MFCs to adjust the cross-substrate resistivity variation of the material layer.

16. The gas injection system of claim 14, wherein: When executed by the one or more processors, the computer readable instructions further cause the controller to: The distribution of dopant flow between the plurality of primary injection ports on the primary manifold and the plurality of auxiliary injection ports on the auxiliary manifold is adjusted by the plurality of second MFCs to adjust the cross-substrate resistivity variation of the material layer.

17. The gas injection system of claim 16, wherein: The ratio of dopants carried by the auxiliary header and the main header is 1 to 4.

18. The gas injection system of claim 1, wherein: When executed by the one or more processors, the computer readable instructions further cause a controller to: The dopant concentration variation across the substrate is adjusted by the plurality of second MFCs to adjust the resistivity variation across the substrate of the material layer.

19. The gas injection system of claim 1, wherein: The carrier source comprises one or more tanks containing a carrier selected from nitrogen, hydrogen and helium.

20. The gas injection system of claim 1, wherein: The precursor source comprises one or more tanks containing a precursor selected from the group consisting of trichlorosilane, dichlorosilane, silane, disilane, trisilane, and silicon tetrachloride.

21. The gas injection system of claim 1, wherein: The dopant source includes one or more tanks containing a dopant selected from the group consisting of germane, diborane, phosphine, arsine, and phosphorus trichloride.

22. A gas flow control method, comprising: depositing a material layer on a substrate by controlling a plurality of first MFCs and a plurality of second MFCs in a gas injection system, the plurality of first MFCs having a first mass flow range, the plurality of second MFCs having a second mass flow range, wherein the first mass flow range is different from the second mass flow range, and wherein the plurality of first MFCs are connected to a precursor source, a dopant source, and a carrier source through a main header, and the plurality of second MFCs are connected to the dopant source and the carrier source through an auxiliary header; adjusting a thickness variation of the material layer across the substrate by controlling the plurality of first MFCs; as well as The cross-substrate resistivity variation of the material layer is adjusted by controlling the plurality of second MFCs and independently of the cross-substrate thickness variation.

23. The gas flow control method according to claim 22, wherein: The values ​​in the second mass flow rate range are between about 1% and about 10% of the values ​​in the first mass flow rate range.

24. The gas flow control method according to claim 22, wherein: The first mass flow range does not overlap with the second mass flow range.

25. A non-transitory machine-readable medium storing instructions, wherein: When executed by one or more processors, the instructions cause the one or more processors to perform the steps comprising: depositing a material layer on a substrate by controlling a plurality of first MFCs and a plurality of second MFCs in a gas injection system, the plurality of first MFCs having a first mass flow range, the plurality of second MFCs having a second mass flow range, wherein the first mass flow range is different from the second mass flow range, and wherein the plurality of first MFCs are connected to a precursor source, a dopant source, and a carrier source through a main header, and the plurality of second MFCs are connected to the dopant source and the carrier source through an auxiliary header; adjusting a thickness variation of the material layer across the substrate by controlling the plurality of first MFCs; as well as The cross-substrate resistivity variation of the material layer is adjusted by controlling the plurality of second MFCs and independently of the cross-substrate thickness variation.

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