Non-metallic thermal CVD/ALD Gas Injector and Purge Systems

Gas distribution assemblies and processing chambers using same are described. The gas distribution assemblies comprise a cooling plate with a quartz puck, a plurality of reactive gas sectors and a plurality of purge gas sectors suspended therefrom. The reactive gas sectors and purge gas sectors having a coaxial gas inlet with inner tubes and outer tubes, the inner tubes and outer tubes in fluid communication with different gas or vacuum ports in the front faces of the sectors. The sectors may be suspended from the cooling plate by a plurality of suspension rods comprising a metal rod body with an enlarged lower end positioned within a quartz frame with a silicon washer around the enlarged lower end.

TECHNICAL FIELD

The present disclosure relates generally to gas distribution apparatus for processing chambers. In particular, the disclosure relates to high temperature quartz gas distribution assemblies for batch processing chambers.

BACKGROUND

Semiconductor device formation is commonly conducted in substrate processing systems or platforms containing multiple chambers, which may also be referred to as cluster tools. In some instances, the purpose of a multi-chamber processing platform or cluster tool is to perform two or more processes on a substrate sequentially in a controlled environment. In other instances, however, a multiple chamber processing platform may only perform a single processing step on substrates. The additional chambers can be employed to maximize the rate at which substrates are processed. In the latter case, the process performed on substrates is typically a batch process, wherein a relatively large number of substrates, e.g. 25 or 50, are processed in a given chamber simultaneously. Batch processing is especially beneficial for processes that are too time-consuming to be performed on individual substrates in an economically viable manner, such as for atomic layer deposition (ALD) processes and some chemical vapor deposition (CVD) processes.

Typical processing chambers use machined aluminum or metal components for the gas distribution assemblies. Metal components are often too thermally conductive for high temperature processes and can melt and/or leach contaminants at high temperatures. Additionally, the high thermal conductivity of metal injectors leaches heat away from the process region resulting in a need to use increased power levels for the heating elements. Accordingly, there is a need in the art for improved injectors for batch processing chambers that are less thermally conductive and are less likely to contaminate the process being performed.

SUMMARY

One or more embodiments of the disclosure are directed to gas distribution assemblies comprising a cooling plate, a plurality of reactive gas sectors axially arranged around a central axis, a plurality of purge gas sectors axially arranged around the central axis and a quartz puck at the central axis. Each of the purge gas sectors are positioned between reactive gas sectors.

Additional embodiments of the disclosure are directed to gas distribution assemblies comprising a cooling plate having a conductive body with a channel therethrough to flow a fluid from an inlet end of the channel to an outlet end of the channel.

A plurality of reactive gas sectors are axially arranged around a central axis. Each of the reactive gas sectors comprises a quartz wedge-shaped housing with a back face, a front face and a coaxial gas inlet in fluid communication with the wedge-shaped housing. The coaxial gas inlet has an inner tube and an outer tube. The inner tube is in fluid communication with a plenum within the wedge-shaped housing and the reactive gas sector includes a diffuser plate adjacent the plenum. The diffuser plate comprises a plurality of apertures to allow a gas flowing through the inner tube to pass into the plenum and diffuse through the plurality of apertures and out the front face of the wedge-shaped housing into a process region of the processing chamber. The outer tube is in fluid communication with a vacuum port in the front face of the wedge-shaped housing. The vacuum port surrounds the diffuser plate of the reactive gas port. Each reactive gas sector is suspended from the cooling plate by at least three suspension rods. Each suspension rod comprises a metal rod body that passes through an opening in the back face of the wedge-shaped housing. The rod body has an enlarged lower end positioned within a quartz frame within the wedge-shaped housing. A silicon washer is positioned within the quartz frame around the enlarged lower end.

A plurality of purge gas sectors are axially arranged around the central axis. Each of the purge gas sectors is positioned between reactive gas sectors and comprises a quartz housing with a back face, a front face, an outer peripheral leg, a radial leg and a coaxial gas inlet in fluid communication with the housing. The coaxial gas inlet has an inner tube and an outer tube. The inner tube is in fluid communication with a purge gas port in the front face of the radial leg of the housing. The outer tube is in fluid communication a purge gas port in the front face of the outer peripheral leg of the housing. Each of the purge gas sectors is suspended from the cooling plate by at least two suspension rods. Each suspension rod comprises a metal rod body that passes through an opening in the back face of the housing. The rod body has an enlarged lower end positioned within a quartz frame within the housing. A silicon washer is positioned within the quartz frame around the enlarged lower end.

A quartz puck is at the central axis. The plurality of reactive gas sectors and purge gas sectors are alternatingly arranged around an outer edge of the quartz puck. The quartz puck comprises at least one vacuum port and at least one purge gas port. The quartz puck is suspended from the cooling plate by a plurality of suspension rods. Each suspension rod comprises a metal rod body that passes through an opening in a back face of the housing. The rod body has an enlarged lower end positioned within a quartz frame within the housing. A silicon washer is positioned within the quartz frame around the enlarged lower end.

Further embodiments of the disclosure are directed to processing chambers comprising a gas distribution assembly and a susceptor assembly. The gas distribution assembly comprising a cooling plate, a quartz puck, a plurality of reactive gas sectors and a plurality of purge gas sectors. The quartz puck is suspended from a central axis of the cooling plate by a plurality of suspension rods. The quartz puck comprises at least one vacuum port and at least one purge gas port in a front face of the quartz puck.

The plurality of reactive gas sectors are axially arranged around an outer edge of the quartz puck. Each reactive gas sector is suspended from the cooling plate by at least three suspension rods. Each of the reactive gas sectors comprises a quartz wedge-shaped housing with a back face, a front face and a coaxial gas inlet in fluid communication with the wedge-shaped housing. The coaxial gas inlet has an inner tube and an outer tube. The inner tube is in fluid communication with a plenum within the wedge-shaped housing and the reactive gas sector includes a diffuser plate adjacent the plenum. The diffuser plate comprises a plurality of apertures to allow a gas flowing through the inner tube to pass into the plenum and diffuse through the plurality of apertures and out the front face of the wedge-shaped housing into a process region of the processing chamber. The outer tube is in fluid communication with a vacuum port in the front face of the wedge-shaped housing. The vacuum port surrounds the diffuser plate of the reactive gas port.

The plurality of purge gas sectors are axially arranged around the outer edge of the quartz puck and alternate with the reactive gas sectors. Each purge gas sector comprises a quartz housing with a back face, a front face, an outer peripheral leg, a radial leg and a coaxial gas inlet in fluid communication with the housing. The coaxial gas inlet has an inner tube and an outer tube. The inner tube is in fluid communication with a purge gas port in the front face of the radial leg of the housing. The outer tube is in fluid communication a purge gas port in the front face of the outer peripheral leg of the housing.

Each suspension rod comprises a metal rod body that passes through an opening in the back face of the housing. The rod body has an enlarged lower end positioned within a quartz frame within the housing and a silicon washer is positioned within the quartz frame around the enlarged lower end.

The susceptor assembly has a top surface comprising a plurality of recesses therein. Each recess is sized to support a substrate. The susceptor assembly has a support post to rotate and move the susceptor assembly to form a gap between the gas distribution assembly and the top surface of the susceptor assembly to form a gap.

DETAILED DESCRIPTION

FIG. 1shows a cross-section of a processing chamber100including a gas distribution assembly120, also referred to as injectors or an injector assembly, and a susceptor assembly140. The gas distribution assembly120is any type of gas delivery device used in a processing chamber. The gas distribution assembly120includes a front surface121which faces the susceptor assembly140. The front surface121can have any number or variety of openings to deliver a flow of gases toward the susceptor assembly140. The gas distribution assembly120also includes an outer edge124which in the embodiments shown, is substantially round.

The specific type of gas distribution assembly120used can vary depending on the particular process being used. Embodiments of the disclosure can be used with any type of processing system where the gap between the susceptor and the gas distribution assembly is controlled. While various types of gas distribution assemblies can be employed (e.g., showerheads), embodiments of the disclosure may be particularly useful with spatial gas distribution assemblies which have a plurality of substantially parallel gas channels. As used in this specification and the appended claims, the term “substantially parallel” means that the elongate axis of the gas channels extend in the same general direction. There can be slight imperfections in the parallelism of the gas channels. In a binary reaction, the plurality of substantially parallel gas channels can include at least one first reactive gas A channel, at least one second reactive gas B channel, at least one purge gas P channel and/or at least one vacuum V channel. The gases flowing from the first reactive gas A channel(s), the second reactive gas B channel(s) and the purge gas P channel(s) are directed toward the top surface of the wafer. Some of the gas flow moves horizontally across the surface of the wafer and out of the process region through the purge gas P channel(s). A substrate moving from one end of the gas distribution assembly to the other end will be exposed to each of the process gases in turn, forming a layer on the substrate surface.

In some embodiments, the gas distribution assembly120is a rigid stationary body made of a single injector unit. In one or more embodiments, the gas distribution assembly120is made up of a plurality of individual sectors (e.g., injector units122), as shown inFIG. 2. Either a single piece body or a multi-sector body can be used with the various embodiments of the disclosure described.

A susceptor assembly140is positioned beneath the gas distribution assembly120. The susceptor assembly140includes a top surface141and at least one recess142in the top surface141. The susceptor assembly140also has a bottom surface143and an edge144. The recess142can be any suitable shape and size depending on the shape and size of the substrates60being processed. In the embodiment shown inFIG. 1, the recess142has a flat bottom to support the bottom of the wafer; however, the bottom of the recess can vary. In some embodiments, the recess has step regions around the outer peripheral edge of the recess which are sized to support the outer peripheral edge of the wafer. The amount of the outer peripheral edge of the wafer that is supported by the steps can vary depending on, for example, the thickness of the wafer and the presence of features already present on the back side of the wafer.

In some embodiments, as shown inFIG. 1, the recess142in the top surface141of the susceptor assembly140is sized so that a substrate60supported in the recess142has a top surface61substantially coplanar with the top surface141of the susceptor140. As used in this specification and the appended claims, the term “substantially coplanar” means that the top surface of the wafer and the top surface of the susceptor assembly are coplanar within ±0.2 mm. In some embodiments, the top surfaces are coplanar within ±0.15 mm, ±0.10 mm or ±0.05 mm.

The susceptor assembly140ofFIG. 1includes a support post160which is capable of lifting, lowering and rotating the susceptor assembly140. The susceptor assembly may include a heater, or gas lines, or electrical components within the center of the support post160. The support post160may be the primary means of increasing or decreasing the gap between the susceptor assembly140and the gas distribution assembly120, moving the susceptor assembly140into proper position. The susceptor assembly140may also include fine tuning actuators162which can make micro-adjustments to susceptor assembly140to create a predetermined gap170between the susceptor assembly140and the gas distribution assembly120.

In some embodiments, the gap170distance is in the range of about 0.1 mm to about 5.0 mm, or in the range of about 0.1 mm to about 3.0 mm, or in the range of about 0.1 mm to about 2.0 mm, or in the range of about 0.2 mm to about 1.8 mm, or in the range of about 0.3 mm to about 1.7 mm, or in the range of about 0.4 mm to about 1.6 mm, or in the range of about 0.5 mm to about 1.5 mm, or in the range of about 0.6 mm to about 1.4 mm, or in the range of about 0.7 mm to about 1.3 mm, or in the range of about 0.8 mm to about 1.2 mm, or in the range of about 0.9 mm to about 1.1 mm, or about 1 mm.

The processing chamber100shown in the Figures is a carousel-type chamber in which the susceptor assembly140can hold a plurality of substrates60. As shown inFIG. 2, the gas distribution assembly120may include a plurality of separate injector units122, each injector unit122being capable of depositing a film on the wafer, as the wafer is moved beneath the injector unit. Two pie-shaped injector units122are shown positioned on approximately opposite sides of and above the susceptor assembly140. This number of injector units122is shown for illustrative purposes only. It will be understood that more or less injector units122can be included. In some embodiments, there are a sufficient number of pie-shaped injector units122to form a shape conforming to the shape of the susceptor assembly140. In some embodiments, each of the individual pie-shaped injector units122may be independently moved, removed and/or replaced without affecting any of the other injector units122. For example, one segment may be raised to permit a robot to access the region between the susceptor assembly140and gas distribution assembly120to load/unload substrates60.

Processing chambers having multiple gas injectors can be used to process multiple wafers simultaneously so that the wafers experience the same process flow. For example, as shown inFIG. 3, the processing chamber100has four gas injector assemblies and four substrates60. At the outset of processing, the substrates60can be positioned between the injector assemblies30. Rotating17the susceptor assembly140by 45° will result in each substrate60which is between gas distribution assemblies120to be moved to a gas distribution assembly120for film deposition, as illustrated by the dotted circle under the gas distribution assemblies120. An additional 45° rotation would move the substrates60away from the injector assemblies30. The number of substrates60and gas distribution assemblies120can be the same or different. In some embodiments, there are the same numbers of wafers being processed as there are gas distribution assemblies. In one or more embodiments, the number of wafers being processed are fraction of or an integer multiple of the number of gas distribution assemblies. For example, if there are four gas distribution assemblies, there are 4x wafers being processed, where x is an integer value greater than or equal to one. In an exemplary embodiment, the gas distribution assembly120includes eight process regions separated by gas curtains and the susceptor assembly140can hold six wafers.

The processing chamber100shown inFIG. 3is merely representative of one possible configuration and should not be taken as limiting the scope of the disclosure. Here, the processing chamber100includes a plurality of gas distribution assemblies120. In the embodiment shown, there are four gas distribution assemblies (also called injector assemblies30) evenly spaced about the processing chamber100. The processing chamber100shown is octagonal; however, those skilled in the art will understand that this is one possible shape and should not be taken as limiting the scope of the disclosure. The gas distribution assemblies120shown are trapezoidal, but can be a single circular component or made up of a plurality of pie-shaped segments, like that shown inFIG. 2.

The embodiment shown inFIG. 3includes a load lock chamber180, or an auxiliary chamber like a buffer station. This chamber180is connected to a side of the processing chamber100to allow, for example the substrates (also referred to as substrates60) to be loaded/unloaded from the chamber100. A wafer robot may be positioned in the chamber180to move the substrate onto the susceptor.

Rotation of the carousel (e.g., the susceptor assembly140) can be continuous or intermittent (discontinuous). In continuous processing, the wafers are constantly rotating so that they are exposed to each of the injectors in turn. In discontinuous processing, the wafers can be moved to the injector region and stopped, and then to the region84between the injectors and stopped. For example, the carousel can rotate so that the wafers move from an inter-injector region across the injector (or stop adjacent the injector) and on to the next inter-injector region where the carousel can pause again. Pausing between the injectors may provide time for additional processing steps between each layer deposition (e.g., exposure to plasma).

FIG. 4shows a sector or portion of a gas distribution assembly220, which may be referred to as an injector unit122. The injector units122can be used individually or in combination with other injector units. For example, as shown inFIG. 5, four of the injector units122ofFIG. 4are combined to form a single gas distribution assembly220. (The lines separating the four injector units are not shown for clarity.) While the injector unit122ofFIG. 4has both a first reactive gas port125and a second gas port135in addition to purge gas ports155and vacuum ports145, an injector unit122does not need all of these components.

Referring to bothFIGS. 4 and 5, a gas distribution assembly220in accordance with one or more embodiment may comprise a plurality of sectors (or injector units122) with each sector being identical or different. The gas distribution assembly220is positioned within the processing chamber and comprises a plurality of elongate gas ports125,135,145in a front surface121of the gas distribution assembly220. The plurality of elongate gas ports125,135,145,155extend from an area adjacent the inner peripheral edge123toward an area adjacent the outer peripheral edge124of the gas distribution assembly220. The plurality of gas ports shown include a first reactive gas port125, a second gas port135, a vacuum port145which surrounds each of the first reactive gas ports and the second reactive gas ports and a purge gas port155.

With reference to the embodiments shown inFIG. 4 or 5, when stating that the ports extend from at least about an inner peripheral region to at least about an outer peripheral region, however, the ports can extend more than just radially from inner to outer regions. The ports can extend tangentially as vacuum port145surrounds reactive gas port125and reactive gas port135. In the embodiment shown inFIGS. 4 and 5, the wedge shaped reactive gas ports125,135are surrounded on all edges, including adjacent the inner peripheral region and outer peripheral region, by a vacuum port145.

Referring toFIG. 4, as a substrate moves along path127, each portion of the substrate surface is exposed to the various reactive gases. To follow the path127, the substrate will be exposed to, or “see”, a purge gas port155, a vacuum port145, a first reactive gas port125, a vacuum port145, a purge gas port155, a vacuum port145, a second gas port135and a vacuum port145. Thus, at the end of the path127shown inFIG. 4, the substrate has been exposed to the first reactive gas and the second reactive gas to form a layer. The injector unit122shown makes a quarter circle but could be larger or smaller. The gas distribution assembly220shown inFIG. 5can be considered a combination of four of the injector units122ofFIG. 4connected in series.

The injector unit122ofFIG. 4shows a gas curtain150that separates the reactive gases. The term “gas curtain” is used to describe any combination of gas flows or vacuum that separate reactive gases from mixing. The gas curtain150shown inFIG. 4comprises the portion of the vacuum port145next to the first reactive gas port125, the purge gas port155in the middle and a portion of the vacuum port145next to the second gas port135. This combination of gas flow and vacuum can be used to prevent or minimize gas phase reactions of the first reactive gas and the second reactive gas.

Referring toFIG. 5, the combination of gas flows and vacuum from the gas distribution assembly220form a separation into a plurality of process regions250. The process regions are roughly defined around the individual gas ports125,135with the gas curtain150between250. The embodiment shown inFIG. 5makes up eight separate process regions250with eight separate gas curtains150between. A processing chamber can have at least two process regions. In some embodiments, there are at least three, four, five, six, seven, eight, nine, 10, 11 or 12 process regions.

During processing a substrate may be exposed to more than one process region250at any given time. However, the portions that are exposed to the different process regions will have a gas curtain separating the two. For example, if the leading edge of a substrate enters a process region including the second gas port135, a middle portion of the substrate will be under a gas curtain150and the trailing edge of the substrate will be in a process region including the first reactive gas port125.

A factory interface280, which can be, for example, a load lock chamber, is shown connected to the processing chamber100. A substrate60is shown superimposed over the gas distribution assembly220to provide a frame of reference. The substrate60may often sit on a susceptor assembly to be held near the front surface121of the gas distribution plate120. The substrate60is loaded via the factory interface280into the processing chamber100onto a substrate support or susceptor assembly (seeFIG. 3). The substrate60can be shown positioned within a process region because the substrate is located adjacent the first reactive gas port125and between two gas curtains150a,150b. Rotating the substrate60along path127will move the substrate counter-clockwise around the processing chamber100. Thus, the substrate60will be exposed to the first process region250athrough the eighth process region250h, including all process regions between.

Embodiments of the disclosure are directed to processing methods comprising a processing chamber100with a plurality of process regions250a-250hwith each process region separated from an adjacent region by a gas curtain150. For example, the processing chamber shown inFIG. 5. The number of gas curtains and process regions within the processing chamber can be any suitable number depending on the arrangement of gas flows. The embodiment shown inFIG. 5has eight gas curtains150and eight process regions250a-250h. The number of gas curtains is generally equal to or greater than the number of process regions.

A plurality of substrates60are positioned on a substrate support, for example, the susceptor assembly140shownFIGS. 1 and 2. The plurality of substrates60are rotated around the process regions for processing. Generally, the gas curtains150are engaged (gas flowing and vacuum on) throughout processing including periods when no reactive gas is flowing into the chamber.

A first reactive gas A is flowed into one or more of the process regions250while an inert gas is flowed into any process region250which does not have a first reactive gas A flowing into it. For example if the first reactive gas is flowing into process regions250bthrough process region250h, an inert gas would be flowing into process region250a. The inert gas can be flowed through the first reactive gas port125or the second gas port135.

The inert gas flow within the process regions can be constant or varied. In some embodiments, the reactive gas is co-flowed with an inert gas. The inert gas will act as a carrier and diluent. Since the amount of reactive gas, relative to the carrier gas, is small, co-flowing may make balancing the gas pressures between the process regions easier by decreasing the differences in pressure between adjacent regions.

Some embodiments of the disclosure are directed to gas distribution assemblies comprising a circular array of non-metallic sectors for precursor gas injection and vacuuming and an array of purge sectors providing both process and peripheral purge. Some embodiments include separate central vacuum/purge inserts within independent purge gas injection and vacuum facility. Introduction of media into injectors and purge sectors may be accomplished through a coaxial piping arrangement. In some embodiments, the various sectors are flexibly suspended from a structural cooling plate of the chamber top.

One or more embodiments advantageously provide non-metallic sectors that provide gas flow with minimal or no metal contamination. Some embodiments advantageously provide gas injectors that are usable at high temperatures which may not be possible with traditional component materials due to melting and leaching issues. Some embodiments advantageously provide injector components with lower thermal conductivity allowing use of lower power for heating.

Referring toFIG. 6, some embodiments of the gas distribution assembly600comprise a cooling plate620with a plurality of reactive gas sectors700,710and a plurality of purge gas sectors800axially arranged around a central axis605. In the embodiment shown, reactive gas sectors700and reactive gas sectors710deliver different gases and may be made from the same or different materials.

FIG. 7shows a cooling plate620in accordance with one or more embodiment of the disclosure. The cooling plate620includes a thermally conductive body622with a top surface624, sidewall626and bottom surface628.

The conductive body622of some embodiments has a channel630extending through the plate to allow a flow of fluid to cool the conductive body622. The channel630can be embedded within the body of the cooling plate620or formed as a recessed channel which is covered by a backing plate. The channel may extend from an inlet end631to an outlet end632following a circuitous route through or across the conductive body622to ensure that the body622is uniformly cooled by the fluid flowing through the channel630. The inlet end631and outlet end632can connect to a fluid hub635which allow fluid communication with an inlet line636and outlet line637.

The conductive body622can be made of any suitable thermally conductive material. Suitable materials include, but are not limited to, aluminum and stainless steel. In some embodiments, the conductive body622comprises aluminum.

A plurality of gas connections640can be connected to the top surface624of the conductive body622. The gas connections640can be configured to allow one or more fluid lines to be attached to the connections640to allow a flow of fluid (e.g., reactive gas, purge gas, vacuum) to pass through the conductive body622.FIG. 8shows a cross-section of an embodiment of a gas connection640with two inlets641,642that flow into a coaxial gas feed. A first gas source (not shown) or vacuum can be connected to the first inlet641on the top643of the gas connection640. The gas can flow through the first inlet641into inner tube644and into region645. A second gas source (not shown) or vacuum can be connected to the second inlet642on the side649of the gas connection640. The gas can flow through the second inlet642into leg646and outer tube647into region648. This allows two different gases or vacuum or combination of gas/vacuum to be connected to a single gas connection640and allow fluid communication between regions645,648which are isolated from each other. The gas connection640shown inFIG. 8is exemplary of one possible connection and should not be taken as limiting the scope of the disclosure. Those skilled in the art will understand that other gas connections and connection configurations are within the scope of the disclosure.

FIGS. 9 through 11show embodiments of a reactive gas sector710. The reactive gas sector710can be structurally identical to reactive gas sector720(shown inFIG. 6) or have different structures, dimensions, etc. The reactive gas sector710has a wedge-shaped housing722with an inner peripheral end723, outer peripheral end724, first side725, second side726, back face727and front face728.

A coaxial gas inlet730is in fluid communication with the wedge-shaped housing722and is shown connected to the back face727. The coaxial gas inlet730has an inner tube731and an outer tube732. The coaxial gas inlet730can have a similar configuration to the gas connection640shown inFIG. 8. In some embodiments, the coaxial gas inlet730passes through the conductive body622of the cooling plate620and acts as both the gas connection640and the coaxial gas inlet730.

The inner tube731is in fluid communication with a plenum740within the wedge-shaped housing722. A diffuser plate742is located adjacent the plenum740and includes a plurality of apertures744to allow a gas flowing through the inner tube731to pass into the plenum740and diffuse through the plurality of apertures744in the diffuser plate742and out the front face728of the wedge-shaped housing722into a process region750of the processing chamber. The process region750is a region located adjacent the front face728of the wedge-shaped housing722where the surface reactions with the substrate can occur.

The outer tube732is in fluid communication with a vacuum port760in the front face728of the wedge-shaped housing722. A plurality of annular openings733in a side of the coaxial gas inlet730allow for coaxial connection of different gas streams (e.g., reactive gas and vacuum) in the inner tube731and outer tube732. As shown inFIG. 10, the vacuum port760surrounds the diffuser plate742of the reactive gas port710. This configuration helps to minimize reactive species from diffusing from the process region750into other areas of the processing chamber. As shown in the partial-cross sectional view ofFIG. 11, the vacuum port760is in fluid communication with the outer tube732through plenum762and apertures764. The outer tube732can be welded to the inner tube731at the top of the coaxial gas inlet730.

In some embodiments, each of the individual layers of the reactive gas sector710is made of quartz and are assembled and fused into a single component. The use of quartz for the layers of the reactive gas sector710minimizes the chances of metal contamination.

Each of the reactive gas sectors710,720are suspended from the cooling plate620by a plurality of suspension rods850. The suspension rod of some embodiments incorporates an encapsulated ball joint to suspend the sector and allow movement of the sector relative to the cooling plate to accommodate, for example, thermal expansion.FIG. 12shows an embodiment of a suspension rod850comprising a metal rod body852that passes through an opening729in the back face727of the wedge-shaped housing722. In the embodiment shown inFIG. 12, the rod body852also extends through an opening629in the conductive body622of the cooling plate620. Those skilled in the art will understand that this is merely representative of one possible configuration and should not be taken as limiting the scope of the disclosure.

The rod body852can be made of any suitable material that can support the weight of the sector and withstand temperature fluctuations encountered within the processing chamber. Suitable materials for the rod body852include, but are not limited to, tungsten, molybdenum, or other high temperature metal that can withstand the fusion process used to assembly the sector components.

The rod body852has an enlarged lower end854which is positioned within a quartz frame860within the wedge-shaped housing722. A washer865is positioned within the quartz frame860and extends around the enlarged lower end854of the rod body852. The washer865can be made of any suitable material including, but not limited to, silicon.

In the embodiment shown inFIG. 12, a seal housing870is positioned adjacent the back face727of the sector710. The seal housing870has two O-rings872,873to form a seal around the rod body852. The O-rings include an O-ring872around the rod body852to form a seal between the rod body852and the seal housing870and an O-ring873between the seal housing870and the back face727of the sector710to form a seal therebetween.

The embodiment ofFIG. 12also shows the rod body852passing through the conductive body622of the cooling plate; however, those skilled in the art will understand that this is merely one possible configuration and that the rod body852does not need to pass through the cooling plate620. The rod body852shown includes an enlarged upper end856within a frame861with a washer866therein. The frame861can be made of any suitable material including, but not limited to, quartz, aluminum or stainless steel. Since the frame861is not inside the sector, the use of a metallic material may be employed without metal contamination issues. The frame861can be connected to the conductive body622, or other component, using screws868, or other fastening components. A spring880, or other compression component, can be used to provide additional support to the sector.

The reactive gas sectors710,720can be suspended by any suitable number of suspension rods. In some embodiments, each of the reactive gas sectors710,720are suspended by at least two suspension rods850. In some embodiments, each of the reactive gas sectors710,720are suspended by at least three suspension rods850.

As shown inFIG. 6, a plurality of purge gas sectors800are axially arranged around the central axis605. Each of the purge gas sectors800is positioned between reactive gas sectors710,720so that each reactive gas sector710,720is separated from adjacent reactive gas sectors by at least one purge gas sector800. In some embodiments, more than one reactive gas sector can be positioned adjacent each other without a purge gas sector800therebetween.

FIGS. 13 to 15show purge gas sectors800in accordance with one or more embodiments of the disclosure. The purge gas sector800include a quartz housing802with a back face803, a front face804, an outer peripheral leg805and a radial leg806with an inner peripheral end807. The purge gas sector800includes a coaxial gas inlet730in fluid communication with the housing802. The coaxial gas inlet730is similar to that of the coaxial gas inlet of the reactive gas sector and has an inner tube731and an outer tube732.

The inner tube731is in fluid communication with a purge gas port810in the front face804of the radial leg806of the housing802. The embodiment shown inFIG. 15has the inner tube731if fluid communication with a plenum812. The plenum812has a diffuser plate814with a plurality of apertures816extending through the diffuser plate814. A gas flowing through the inner tube731will pass into the plenum812, flow through the apertures816in the diffuser plate814and out the front face804of the radial leg806of the housing802through the purge gas port810.

The outer tube732is in fluid communication a purge gas port820in the front face804of the outer peripheral leg805of the housing802. The embodiment shown inFIG. 15has the outer tube732in fluid communication with a plenum822. The plenum has a diffuser plate824with a plurality of apertures826extending through the diffuser plate824. A gas flowing through the outer tube732will pass into the plenum822, flow through the apertures826in the diffuser plate824and out the front face804of the outer peripheral leg805of the housing802through the purge gas port820.

In some embodiments, each of the purge gas sectors800are suspended from the cooling plate620by at least two suspension rods850. In some embodiments, each of the purge gas sectors800are suspended from the cooling plate620by at least three suspension rods850.

Some embodiments, as shown inFIG. 6, include a quartz puck650at the central axis605of the gas distribution assembly600.FIGS. 16 through 19show a quartz puck650in accordance with one or more embodiment of the disclosure. The quartz puck650has a body651with an outer edge652, a back face653and a front face654. The quartz puck650can be positioned at and act as a central axis605so that each of the reactive gas sectors710,720and purge gas sectors800are alternatingly arranged around an outer edge652of the quartz puck650.

The quartz puck650comprises at least one vacuum port660and at least one purge gas port670. The quartz puck650of some embodiments comprises, as shown inFIG. 18, a plurality of vacuum ports660and purge gas ports670. As shown inFIG. 19, some embodiments of the quartz puck650include one vacuum port660and one purge gas port670. While not shown inFIG. 18 or 19, a plurality of apertures may be formed in the vacuum port660and/or purge gas port670to allow fluid communication between the ports and the gas or vacuum source.

A vacuum connection661passes through the back face653of the quartz puck650and is in fluid communication with a vacuum plenum662. In the embodiment shown, a plurality of apertures663form a fluid connection between the vacuum plenum662and the vacuum port660in the front face654of the quartz puck650.

A purge gas connection671passes through the back face653of the quartz puck650and is in fluid communication with a purge gas plenum672. In the embodiment shown, a plurality of apertures673form a fluid connection between the purge gas plenum672and the purge gas port670in the front face654of the quartz puck650.

The quartz puck650can be suspended from the cooling plate620by a plurality of suspension rods850. In some embodiments, the quartz puck650is suspended from the cooling plate620by at least three suspension rods850. In some embodiments, the quartz puck650is suspended from the cooling plate620by four, or at least four, suspension rods850.

According to one or more embodiments, the processing apparatus may comprise multiple chambers in communication with a transfer station. An apparatus of this sort may be referred to as a “cluster tool” or “clustered system,” and the like.

Generally, a cluster tool is a modular system comprising multiple chambers which perform various functions including substrate center-finding and orientation, annealing, annealing, deposition and/or etching. According to one or more embodiments, a cluster tool includes at least a first chamber and a central transfer chamber. The central transfer chamber may house a robot that can shuttle substrates between and among processing chambers and load lock chambers. The transfer chamber is typically maintained at a vacuum condition and provides an intermediate stage for shuttling substrates from one chamber to another and/or to a load lock chamber positioned at a front end of the cluster tool. Two well-known cluster tools which may be adapted for the present disclosure are the Centura® and the Endura®, both available from Applied Materials, Inc., of Santa Clara, Calif. However, the exact arrangement and combination of chambers may be altered for purposes of performing specific steps of a process as described herein. Other processing chambers which may be used include, but are not limited to, cyclical layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), etch, pre-clean, chemical clean, thermal treatment such as RTP, plasma nitridation, anneal, orientation, hydroxylation and other substrate processes. By carrying out processes in a chamber on a cluster tool, surface contamination of the substrate with atmospheric impurities can be avoided without oxidation prior to depositing a subsequent film.

According to one or more embodiments, the substrate is continuously under vacuum or “load lock” conditions, and is not exposed to ambient air when being moved from one chamber to the next. The transfer chambers are thus under vacuum and are “pumped down” under vacuum pressure. Inert gases may be present in the processing chambers or the transfer chambers. In some embodiments, an inert gas is used as a purge gas to remove some or all of the reactants. According to one or more embodiments, a purge gas is injected at the exit of the deposition chamber to prevent reactants from moving from the deposition chamber to the transfer chamber and/or additional processing chamber. Thus, the flow of inert gas forms a curtain at the exit of the chamber.

The substrate can be processed in single substrate deposition chambers, where a single substrate is loaded, processed and unloaded before another substrate is processed. The substrate can also be processed in a continuous manner, similar to a conveyer system, in which multiple substrate are individually loaded into a first part of the chamber, move through the chamber and are unloaded from a second part of the chamber. The shape of the chamber and associated conveyer system can form a straight path or curved path. Additionally, the processing chamber may be a carousel in which multiple substrates are moved about a central axis and are exposed to deposition, etch, annealing, cleaning, etc. processes throughout the carousel path.

During processing, the substrate can be heated or cooled. Such heating or cooling can be accomplished by any suitable means including, but not limited to, changing the temperature of the substrate support and flowing heated or cooled gases to the substrate surface. In some embodiments, the substrate support includes a heater/cooler which can be controlled to change the substrate temperature conductively. In one or more embodiments, the gases (either reactive gases or inert gases) being employed are heated or cooled to locally change the substrate temperature. In some embodiments, a heater/cooler is positioned within the chamber adjacent the substrate surface to convectively change the substrate temperature.

The substrate can also be stationary or rotated during processing. A rotating substrate can be rotated continuously or in discreet steps. For example, a substrate may be rotated throughout the entire process, or the substrate can be rotated by a small amount between exposures to different reactive or purge gases. Rotating the substrate during processing (either continuously or in steps) may help produce a more uniform deposition or etch by minimizing the effect of, for example, local variability in gas flow geometries.

In atomic layer deposition type chambers, the substrate can be exposed to the first and second precursors either spatially or temporally separated processes. Temporal ALD is a traditional process in which the first precursor flows into the chamber to react with the surface. The first precursor is purged from the chamber before flowing the second precursor. In spatial ALD, both the first and second precursors are simultaneously flowed to the chamber but are separated spatially so that there is a region between the flows that prevents mixing of the precursors. In spatial ALD, the substrate is moved relative to the gas distribution plate, or vice-versa.

In embodiments, where one or more of the parts of the methods takes place in one chamber, the process may be a spatial ALD process. Although one or more of the chemistries described above may not be compatible (i.e., result in reaction other than on the substrate surface and/or deposit on the chamber), spatial separation ensures that the reagents are not exposed to each in the gas phase. For example, temporal ALD involves the purging the deposition chamber. However, in practice it is sometimes not possible to purge the excess reagent out of the chamber before flowing in additional regent. Therefore, any leftover reagent in the chamber may react. With spatial separation, excess reagent does not need to be purged, and cross-contamination is limited. Furthermore, a lot of time can be used to purge a chamber, and therefore throughput can be increased by eliminating the purge step.