METHOD AND APPARATUS FOR GAS DELIVERY IN A PROCESSING CHAMBER

Disclosed herein are a gas delivery module, a processing chamber, and a method for depositing a film on a substrate. In one example, a gas delivery module is provided that includes a deposition precision flow device (PFD) flow controller, a carrier PFD flow controller, and a plurality of mass flow controllers (MFCs). The deposition PFD flow controller is configured to control a flow of a deposition gas through a plurality of outlets. The carrier PFD flow controller is configured to control a flow of a carrier gas through a plurality of outlets. The first MFC of the plurality of MFCs includes a first inlet and an outlet. The first inlet of the first MFC is fluidly coupled to a first outlet of the plurality of outlets of the deposition PFD and to a first outlet of the plurality of outlets of the carrier PFD. The second MFC of the plurality of MFCs includes a second inlet and an outlet. The second inlet of the second MFC is fluidly coupled to a second outlet of the plurality of outlets of the deposition PFD and to a second outlet of the plurality of outlets of the carrier PFD. The third MFC of the plurality of MFCs includes a third inlet and an outlet. The third inlet of the third MFC is fluidly coupled to a third outlet of the plurality of outlets of the deposition PFD and to a third outlet of the plurality of outlets of the carrier PFD.

BACKGROUND

Field

The present disclosure relates to components and epitaxial system that includes precision gas delivery system comprised of a plurality of flow controllers and inlets, and more specifically to system and method for depositing a film on a substrate. In one or more embodiments, the gas delivery system facilitates the gas flow for processing a substrate in a processing chamber.

Description of the Related Art

Semiconductor substrates are processed for a wide variety of applications, including the fabrication of integrated devices and microdevices. One method of processing substrates includes deposing a material, such as a semiconductor or conductive material on a surface of a substrate. Epitaxy is one deposition process that refers to processes used to grow a thin crystalline layer (epi layer) on a crystalline substrate. The epi layer on a semiconductor substrate facilitates formation of highly complex microprocessors and memory devices.

Non-uniformities can exist for gas flow, for example, gas concentrations, gas temperatures, and/or flow rates. Gas properties, such as temperature and expansion, gas concentration, and flow rate, can affect control and adjustability, thermal uniformity and deposition uniformity, such as center-to-edge film thickness uniformity. Complex operations can further exacerbate existing issues from non-uniformities and lack of control of gas properties. Precise control of the concentration, flow rate and injection location into the processing chamber is lacking in conventional designs.

Thus, a need exists for an improved apparatus and methods for reliably controlling gas flow for processing a substrate in a processing chamber.

SUMMARY

Disclosed herein are a gas delivery module, a processing chamber, and a method for depositing a film on a substrate. In one example, a gas delivery module is provided that includes a deposition precision flow device (PFD) flow controller, a carrier PFD flow controller, and a plurality of mass flow controllers (MFCs). The deposition PFD flow controller is configured to control a flow of a deposition gas through a plurality of outlets. The carrier PFD flow controller is configured to control a flow of a carrier gas through a plurality of outlets. The first MFC of the plurality of MFCs includes a first inlet and an outlet. The first inlet of the first MFC is fluidly coupled to a first outlet of the plurality of outlets of the deposition PFD and to a first outlet of the plurality of outlets of the carrier PFD. The second MFC of the plurality of MFCs includes a second inlet and an outlet. The second inlet of the second MFC is fluidly coupled to a second outlet of the plurality of outlets of the deposition PFD and to a second outlet of the plurality of outlets of the carrier PFD. The third MFC of the plurality of MFCs includes a third inlet and an outlet. The third inlet of the third MFC is fluidly coupled to a third outlet of the plurality of outlets of the deposition PFD and to a third outlet of the plurality of outlets of the carrier PFD.

In yet another example, a processing chamber is provided that includes a chamber body, a plurality of optically transparent windows, a susceptor, and a gas delivery module. The transparent windows are disposed on the chamber body and with the body, partially enclosing a processing volume. The susceptor is disposed in the processing volume. The gas delivery module provided includes a deposition precision flow device (PFD) flow controller, a carrier PFD flow controller, and a plurality of mass flow controllers (MFCs). The deposition PFD flow controller is configured to control a flow of a deposition gas through a plurality of outlets. The carrier PFD flow controller is configured to control a flow of a carrier gas through a plurality of outlets. The first MFC of the plurality of MFCs includes a first inlet and an outlet. The first inlet of the first MFC is fluidly coupled to a first outlet of the plurality of outlets of the deposition PFD and to a first outlet of the plurality of outlets of the carrier PFD. The second MFC of the plurality of MFCs includes a second inlet and an outlet. The second inlet of the second MFC is fluidly coupled to a second outlet of the plurality of outlets of the deposition PFD and to a second outlet of the plurality of outlets of the carrier PFD. The third MFC of the plurality of MFCs includes a third inlet and an outlet. The third inlet of the third MFC is fluidly coupled to a third outlet of the plurality of outlets of the deposition PFD and to a third outlet of the plurality of outlets of the carrier PFD.

In still another example, a method for depositing a film on a substrate is provided that includes directing a deposition gas into a deposition PFD flow controller; directing a carrier gas into a carrier gas PFD flow controller; outputting the deposition gas from the PFD flow controller into a first set of independent output channels; outputting the carrier gas from the PFD flow controller into a second set of independent output channels different than the first set; merging each channel of the first set of output channels with a corresponding channel of the second set of output channels; directing the merged channels to respective MFCs; outputting gas from each MFC to a respective injection channel of processing chamber; and depositing a film on a substrate in the processing chamber.

DETAILED DESCRIPTION

Disclosed herein are a processing chamber, a gas flow system, and a method for depositing a film on a substrate. The apparatus and method both utilize a precision gas delivery system to inject gas through an inlet of an epitaxial deposition chamber, or other suitable processing chamber. In one example, the flow of each a deposition gas and a carrier gas are controlled independently by precision flow device (PFD) flow controllers, which are directed into separate channels in an inlet into an epitaxial deposition chamber by mass flow controllers (MFC). The MFCs are configured to direct the flow of the deposition gas and the carrier gas into multiple channels to evenly distribute (e.g., spatially) the deposition gases over the substrate to facilitate uniform deposition.

When a processing a semiconductor substrate in an epitaxial deposition chamber, maintaining uniform deposition across the surface of a semiconductor substrate can be challenging. Flow of the deposition gas impacts deposition rate and uniformity, and a large gradient in the flow of the deposition gas across the substrate can cause the epitaxial layer to have relatively large variations in terms of thickness and electrical resistivity throughout the deposited material.

According to an embodiment of the present application, PFDs are fluidly coupled to a plurality of MFCs in a gas delivery module fluidly coupled to a plurality of inlet openings of the processing chamber. The openings are spaced at intervals along a semicircular portion of the processing chamber. The gas delivery module, by way of the MFCs, flows a precise amount of each the deposition gas and the carrier gas through each inlet opening based on a variety of parameters including gas concentration, deposition rate, and gas expansion. The gas mixture containing the deposition gas and a carrier gas is precisely flowed into the chamber by the MFCs of the gas delivery module such that the concentration of the deposition material to be deposited on the substrate is controllable throughout the epitaxial deposition chamber.

According to a general aspect of the present application, a carrier gas is precisely mixed with a deposition gas by PFDs and is injected into a plurality of MFCs prior to entrance into the epitaxial deposition chamber. The deposition containing gas can include, for example, one or more reactive gasses. In some examples, the deposition gas may be silicon and/or germanium containing gasses, or other suitable reactive gases, such as silane (SiH4), disilane (Si2H6), dichlorosilane (SiH2Cl2), trichlorosilane, and/or germane (GeH4), chlorine containing etching gases, such as hydrogen chloride (HCl), and/or dopant gases, such as phosphine (PH3) and/or diborane (B2H6). The deposition gas is then used to processes the substrate by, for example, depositing a film on a substrate, or selectively etching the substrate.

Turning now toFIG.1,FIG.1illustrates a schematic top view of a processing system100, according to one or more embodiments. The processing system100includes one or more load lock chambers122(two are shown inFIG.1), a processing platform104, a factory interface102, and a controller144. In one or more embodiments, the processing system100is a CENTURA® integrated processing system, commercially available from Applied Materials, Inc., located in Santa Clara, California. It is contemplated that other processing systems (including those from other manufacturers) may be adapted to benefit from the disclosure.

The platform104includes a plurality of processing chambers110,112,120,128, and the one or more load lock chambers122that are coupled to a transfer chamber136. The transfer chamber136can be maintained under vacuum, or can be maintained at an ambient (e.g., atmospheric) pressure. Two load lock chambers122are shown inFIG.1. The factory interface102is coupled to the transfer chamber136through the load lock chambers122.

In one or more embodiments, the factory interface102includes at least one docking station109and at least one factory interface robot114to facilitate the transfer of substrates. The docking station109is configured to accept one or more front opening unified pods (FOUPs). Two FOUPS106A,106B are shown in the implementation ofFIG.1. The factory interface robot114having a blade116disposed on one end of the robot114is configured to transfer one or more substrates from the FOUPS106A,106B, through the load lock chambers122, to the processing platform104for processing. Substrates being transferred can be stored at least temporarily in the load lock chambers122.

Each of the load lock chambers122has a first port interfacing with the factory interface102and a second port interfacing with the transfer chamber136. The load lock chambers122are coupled to a pressure control system (not shown) which pumps down and vents the load lock chambers122to facilitate passing the substrates between the environment (e.g., vacuum environment or ambient environment, such as atmospheric environment) of the transfer chamber136and a substantially ambient (e.g., atmospheric) environment of the factory interface102.

The transfer chamber136has a vacuum robot130disposed therein. The vacuum robot130has one or more blades134(two are shown inFIG.1) capable of transferring the substrates124between the load lock chambers122and the processing chambers110,112,120,128.

The controller144is coupled to the processing system100and is used to control processes and methods, such as the operations of the methods described herein (for example the operations of the method800). The controller144includes a central processing unit (CPU)138, a memory140containing instructions, and support circuits142for the CPU. The controller144controls various items directly, or via other computers and/or controllers.

FIG.2illustrates a schematic cross-sectional view of an epitaxial deposition processing chamber200according to an embodiment. The epitaxial deposition processing chamber may be used in place of any of processing chambers110,112,120,128. The epitaxial deposition processing chamber200is a deposition chamber configured for growth of an epitaxial layer on a substrate202. A controller144is in communication with the processing chamber200and is used to control processes performed in, and function of, the processing chamber200. The controller144may be a slave of the controller144illustrated inFIG.1, or may be an integral component (hardware of software) of the controller144.

The processing chamber200includes an upper body256, a lower body248disposed below the upper body256, and a chamber body212disposed between the upper body256and the lower body248. An upper window208(such as an upper dome) and a lower window210(such as a lower dome) are disposed on the upper and lower surfaces of the chamber body212to enclose a processing volume204. The windows208,210are generally substantially transparent to radiant energy at predetermined wavelengths. A susceptor206is disposed in the processing volume236and configured to support a substrate202thereon during processing.

A plurality of upper heat sources241are disposed in the upper body256above the upper window208and below a lid254enclosing the upper body256. The plurality of upper heat sources241are configured to direct radiant energy through the upper window208toward the susceptor206and a top surface250of the substrate202disposed thereon. Similarly, a plurality of lower heat sources243are disposed below the lower window210. The plurality of lower heat sources243are configured to direct radiant energy through the lower window210toward the bottom of the susceptor206.

According to an embodiment, the heat sources241,243are lamps that are capable of generating infrared radiation. Other heat sources that are capable of generating infrared radiation are contemplated, such as resistive heaters, light emitting diodes (LEDs), and/or lasers.

The plurality of lower heat sources243are disposed between the lower window210and a chamber floor252. The plurality of lower heat sources243form a portion of a lower heating module245. The upper window208is an upper dome and is formed at least partially of an energy transmissive material, such as quartz. The lower window210is a lower dome and is formed at least partially of an energy transmissive material, such as quartz.

The susceptor206is supported in the processing chamber by a plurality of arms234coupled to an inner shaft218. The inner shaft218is coupled to a motion assembly221includes one or more actuators and/or motors that provide vertical and/or rotational movement of the inner shaft218, which, in turn, moves susceptor206and the substrate202disposed thereon. Lift pin holes207are formed through the susceptor206and are each sized to accommodate lift pins232that is used to lift the substrate202during substrate transfer into and out of the chamber body212through a slit valve. The relative elevation of the inner shaft218may be changed to cause a lift pins stop233to displace the lift pins232through the susceptor206, thus lifting the substrate202above the susceptor206to allow access by a robot blade (not shown) that moves the substrate202into and out of the processing chamber200.

The chamber body212includes a plurality of gas inlets214, a plurality of purge gas inlets264, and one or more gas exhaust outlets216. The plurality of gas inlets214are generally aligned in a horizontal plane, but it is contemplated that plurality of gas inlets214may be aligned in an array. The gas inlets214are connected with a gas delivery system251(shown in more detail inFIG.4) and provides a cross-flow of processing gases across the top surface250of the substrate202. A liner213(which may include separable upper and lower portions) is positioned radially inward of the chamber body212. The liner213includes one or more gas passages215formed therein to facilitate process gas flow into the processing volume236along gas flow path P1.

The gas delivery system251generally provides a deposition gas, etchant gas, doping gas, and/or carrier gas to an upper surface of the substrate202. In one example, the plurality of gas inlets214are disposed at an elevation above or coplanar with the susceptor206when the substrate is in an elevated (e.g., deposition) processing position. The purge gas inlets264are connected with a purge gas source262and provide purge gas to the epitaxial deposition processing chamber200to reduce backside deposition on the substrate202.

The plurality of gas inlets214and the plurality of purge gas inlets264are disposed on the opposite side of the chamber body212from the one or more gas exhaust outlets216. The one or more gas exhaust outlets216are connected an exhaust conduit278. The exhaust conduit278fluidly connects the one or more gas exhaust outlets216formed through the chamber body212to an exhaust pump257that evacuates the processing volume236and gases flowing into the processing volume236from at least the gas inlets214.

FIG.3illustrates a top schematic view of a chamber body shown inFIG.2, according to one or more embodiments.

The chamber body212is a ring shape, with an inner wall that engages the liner213. The liner213is exposed to and defines the processing volume236. The chamber body212has plurality of gas inlets214a-214i(more or less openings are contemplated) formed through a wall of the chamber body212to facilitate process gas ingress to the processing volume236. An insert301, such as an injector, is coupled to the base of the chamber body212. The insert301may be bolted to and/or disposed in a corresponding recess of the chamber body212to facilitate coupling between the chamber body212and the insert301. The insert301includes a plurality of guide channels therein (for example, 5 channels-one central, two middle, and two outer) which direct process gases to the plurality of gas inlets214a-214i.

The gas delivery system251is coupled to the insert301by a plurality of conduits351a-351e. The plurality of conduits35a-351eallow for independent flow control of a center zone372, middle zones371a-371b, and outer zones370a-370bof the insert301. The independent control of the center zone372, middle zones371a-371b, and outer zones370a-370ballows for improved uniformity of the process gases to the processing region313, thereby improving deposition uniformity on the substrate202. While five conduits351a-351eare shown (corresponding to five zones), it is contemplated that more or less conduits (and thus more or less zones) may be utilized depending on the level of uniformity control that is desired. The insert301is located opposite of (e.g., 180 degrees from) exhaust outlet216and exhaust conduit278.

While not shown, the chamber body212may include an opening formed therein to facilitate ingress and egress of the substrate202into the processing volume236. In such an example, the opening is a slit valve which is selectively opened and closed via a slit valve door. In one example, the slit valve is approximately 90 degrees from a centerline of the insert301.

FIG.4is a block diagram of a gas delivery system251of the epitaxial deposition processing chamber200ofFIG.2, according to an embodiment of the present application. The gas delivery system251includes a deposition gas source401, a carrier gas source402, and optionally one or more other gas sources403a,403b(two are shown, but is contemplated that a single gas source403may be utilized). Additionally, the gas delivery system251includes a plurality of precision flow device (PFD) flow controllers404,405, as well as a plurality of mass flow controllers (MFCs)406-408. PFDs can be used to divide volumetric gas flow into a controllable ratio. Although PFDs are disclosed herein, a number of devices can be used to divide volumetric gas flow into a controllable ratio, such as a flow divider. MFCs can be used to measure the mass and/or volume flow and temperature of a gas through the line. Although MFCs are disclosed herein, any type of flow controller can be used, such as back pressure controllers or volumetric flow controllers, or any other device that can measure and control the mass and/or volume flow and temperature of a gas through a line. In one example, the carrier gas provided by the carrier gas source402is mixed with processing gas provided by the process gas source403bprior to delivery to the gas inlets214, such as by way of a conduit upstream of the plurality of PFDs404,405and MFCs406-408or by way of the plurality of PFDs404,405. Similarly, in another example, the deposition gas provided by the deposition gas source401is mixed with processing gas provided by the process gas source403aprior to delivery to the gas inlets214, such as by way of a conduit upstream of the plurality of PFDs404,405and MFCs406-408or by way of the plurality of PFDs404,405.

The deposition gas source401and the other process gas source403aeach have a respective output480,481coupled to an input of a PFD flow controller404via common line482. While the deposition gas of the deposition gas source401and the other process gas of the other process gas source403aare mixed before the input of the deposition PFD flow controller404, it is contemplated that alternatively the deposition gas of the deposition gas source401and the other process gas of the other process gas source403aare mixed at the input of the deposition PFD flow controller404.

The carrier gas source402and the other process gas source403beach have a respective output483,484coupled to an input of a PFD flow controller405via a common line485. While the carrier gas of the carrier gas source402and the other process gas of the other process gas source403bare illustrated as mixed before the input of the carrier PFD flow controller405it is contemplated, the carrier gas of the carrier gas source402and the other process gas of the other process gas source403may alternatively be mixed at the input of the carrier PFD flow controller405.

The deposition PFD flow controller404is downstream of the deposition gas source401and the other process gas source403a. The deposition PFD flow controller404is configured to control parameters of the flow of the mixture of the deposition gas other process gases. For example, the deposition PFD flow controller404controls the flow rate and/or the concentration of deposition gas by adjusting the flow rate of deposition gas from the deposition gas source401and other process gases from the other process gas source403a.

The carrier PFD flow controller405is located downstream of the carrier gas source402and the other process gas source403b. The carrier PFD flow controller is configured to control parameters of the flow of the mixture of the carrier gas optionally other process gases. For example, the carrier PFD flow controller405controls the flow rate and/or concentration of carrier gas from the carrier gas source402and other process gas from the other process gas source403b.

Each PFD flow controller404,405has a plurality of outputs configured to control the output flow of respective gas mixtures therefrom. The outputs of the PFD flow controllers404,405, are configured to interface with a plurality of MFCs. In some embodiments, each PFD flow controller404,405has a plurality of outputs, wherein each output of the PFD flow controller404,405flows the gas mixture to one of the plurality of MFCs. In the embodiment shown inFIG.4, each PFD flow controller404,405has three outputs. For example, the outputs486a-486cfrom the PFD flow controller404are fluidly coupled to respective MFCs406,407, and408. Similarly, the outputs487a-487cfrom the PFD flow controller404are fluidly coupled to respective MFCs406,407, and408

In some examples, the volumetric ratio of gases provided to the plurality of MFCs406,407,408are different. In one instance, an amount of deposition gas mixture provided from the deposition PFD flow controller404to the plurality of MFCs406,407,408is greater than an amount of carrier gas mixture provided from the carrier PFD flow controller to the plurality of MFCs406,407,408. In another instance, an amount of deposition gas mixture provided from the deposition PFD flow controller to the plurality of MFCs406,407,408is less than an amount of carrier gas mixture provided from the carrier PFD flow controller to the plurality of MFCs406,407,408. In other embodiments, each of the MFCs406,407,408receives a different volumetric flow rate of gas from the deposition PFD flow controller404and the carrier PFD flow controller405, thus facilitating uniform film deposition. During operation, deposition gas mixture from the deposition PFD flow controller404and carrier gas mixture from the carrier PFD flow controller405are merged into a common conduit488upstream of the MFC406. Similarly, deposition gas mixture from the deposition PFD flow controller404and carrier gas mixture from the carrier PFD flow controller405are merged into a common conduit489,490upstream of the MFCs407,408, respectively.

Each MFC406,407,408is configured to control parameters of the flow of the gas mixture, such as flow rate and temperature. Each MFC406-408has at least one output configured to flow the gas mixture into an inject channel of a processing chamber. In some embodiments, each MFC406-408may have two or more outputs configured to flow the gas mixture into respective inject channels. In the embodiment shown inFIG.4, outer inject MFC407and middle inject MFC408each have two outputs, and inner inject MFC406has one output. Specifically, the MFC406has a single outlet coupled to an inner inject channel372by a conduit351c. The MFC408has two independent outlets coupled to the middle inject channels371a,371bby respective conduits351b.351d. The MFC407has two independent outlets coupled to the outer inject channels370a,370bby respective conduits351a,351e. The independent channels between the MFCs406-408and the inject channels370a,370b,371a,371b, and372facilitate enhanced process gas control, resulting in improved deposition uniformity.

Each MFC406,407,408is configured to be operable independently of each other MFC406,407,408. By way of example, the inner inject MFC406can flow one hundred percent of the total gas flow into the inner inject channel409and into the processing chamber200, while the outer inject MFC407and middle inject MFC408flow zero percent of the total gas flow into the processing chamber200. In yet another embodiment the ratio of total gas flow into the processing chamber may be split 20% of the total gas flow from the inner inject MFC406into the inner inject channel409, 30% of the total gas flow from the middle inject MFC408into the middle inject channels411and 50% of the total gas flow from the outer inject MFC407into the outer inject channels410. In yet another embodiment the ratio of total gas flow into the processing chamber may be split 5% of the total gas flow from the inner inject MFC406into the inner inject channel409, 30% of the total gas flow from the middle inject MFC408into the middle inject channels411and 65% of the total gas flow from the outer inject MFC407into the outer inject channels410. Other flow ratios are also contemplated, and the above examples are included for illustration and are not intended to be limiting. In some embodiments the flow ratios are determined by trials run with test wafers. The rations can be adjusted for recipes based on the trial deposition film measurements.

As the gas flows into the gas delivery module310, the PFDs and MFCs are operable to control the concentration and flow rate of the gases flowing into the processing volume236through the gas delivery module. Moreover, the PFDs are operable to control the concentration of the deposition gas output into each MFC over time and independent of each other MFC. In one embodiment, the deposition PFD flow controller404can output a concentration of deposition gas to the inner inject MFC406that is less than the concentration of deposition gas that is output to the middle inject MFC408and outer inject MFC407. In another embodiment, the deposition PFD flow controller404and carrier PFD flow controller405can output a concentration of the deposition gas401and the carrier gas402to the MFCs406,407,408that is changeable over time. In yet another embodiment, the deposition PFD flow controller404and carrier PFD flow controller405can output a modifiable concentration of the deposition gas401and the carrier gas402to each of the MFCs406,407,408independently of the each other MFC406,407,408, changeable based on controlled processing parameters or in real time based on observed properties and parameters inside of the processing volume236.

Gas properties can dictate the movement and functions of the gas, which can change due to the environment, such as the temperature, the pressure, and the volume of the gas. Depending on the environment inside of the processing chamber200, the deposition gas401and the carrier gas402will have different properties and the gas molecules will excite, expand, contract, and move in certain ways. The system and method, such as shown and described herein, provides for improved processing uniformity by flowing the deposition gas401and the carrier gas402in based at least in part on the gas properties, to account for downstream non-uniformities. In some embodiments the parameters of the plurality of PFD flow controllers and MFCs is determined in advance of processing a substrate in a chamber. In some embodiments, the gas flow controlled by the deposition PFD flow controller404, the carrier PFD flow controller405, the inner inject MFC406, the outer inject MFC407, and the middle inject MFC408is determined in advance of processing by a simulated procedure to determine settings of each device. In some embodiments the gas flow controlled by the deposition PFD flow controller404, the carrier PFD flow controller405, the inner inject MFC406, the outer inject MFC407, and the middle inject MFC408is changeable throughout processing, such as real time modifications to the parameters. The flexibility to adjust the concentration of deposition gas401to carrier gas402by way of the PFD flow controllers404,405, and the flow rate into each inject channel370a-b,371a-b,372allows for tunability of the system based on the gas properties in the processing volume236to enable improved uniformity of the deposition on the substrate. In some examples, the deposition gas has a greater influence on film growth rate and/or deposition rate than a carrier gas. In some examples, the expansion of the gas in the processing volume236from one of the inject channels370,371,372may expand into another of the inject channels370,371,372(or flow path thereof) due to a pressure differential in the chamber. In some embodiments, individual control of each a deposition PFD flow controller404and a carrier PFD flow controller405allows for adjustment of the gas expansion by compensating total gas flow through each channel with an increased ratio of carrier gas to deposition gas in the total gas flow. Thus, gas expansion can be controlled between inject channels without alteration of the deposition gas distribution, resulting in improved processing uniformity.

FIG.5is a schematic block diagram view of a method500of processing substrates for semiconductor manufacturing, according to an embodiment of the present application. Method500begins at operation501, in which a deposition gas and optionally other gases are directed into a deposition PFD flow controller. Similarly, in operation502, a carrier gas and optionally other gases are directed into a carrier PFD flow controller. The PFD flow controllers facilitate enhanced control of volumetric flow rates and concentrations over standard valving/meters (or when using MFCs alone), particular in light of elevated temperatures which can occur during semiconductor manufacturing, thereby improving deposition uniformity.

In operation503, deposition gas from the deposition PFD flow controller is output into multiple independent output channels. Similarly, carrier gas from the carrier PFD flow controller is output into multiple independent output channels in operation504. In operation505, each output channel from the deposition PFD flow controller is merged with an output channel of the carrier PFD flow controller. The merged channels have more accurate flow rates and concentrates than conventional systems due to the use of the PFDs.

In operation506, the merged channels are then directed into respective MFCs. The outputs of the MFCs are then provided to injection channels of an epitaxial deposition chamber to facilitate film formation on a substrate.

The use of both PFDs and MFCs during the injection process results in increased gas concentration control and flow uniformity, which ultimately results in more uniformity deposition. By independently controlling the concentration of the deposition gas from the carrier gas into each inject channel, the uniformity of gas flow inside of the processing volume can be tuned precisely based on the parameters inside of the processing volume. Independent PFD flow controllers for a deposition gas and a carrier gas allow for a precise flow rate of each respective gas into an MFC controlling the gas flow into the chamber. Deposition rate can be affected by a variety of parameters including, for example, temperature, hardware configuration, gas concentration, and gas velocity. Based on the parameters of the gas and inside the processing volume, independent control of the deposition gas flow rate and the carrier gas flow rate, the ratio of deposition gas to carrier gas, and the channel of the flow of gas into the processing volume may be adjusted to compensate for the parameters and to control the direction of gas expansion between inject channels. As gas expansion occurs, and other parameters change during the processing of a substrate, the control of gas concentration via independent PFD flow controllers for each gas source, and control of gas flow into channels of the chamber via independent MFCs allows for precise tunability and uniform deposition. In some embodiments, the control of the gas via the PFD flow controllers and the MFCs are changeable during the process of deposition. In some embodiments, the control of the gas via the PFD flow controllers and the MFCs are set by a recipe determined in advance of the deposition process.

Is contemplated that one or more aspects disclosed herein may be combined. Moreover, it is contemplated that one or more aspects disclosed herein may include some or all of the aforementioned benefits. While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.