TW201546948A - Integrated two-axis lift-rotation motor center pedestal in multi-wafer carousel ALD - Google Patents

Abstract

Apparatus and methods for processing a semiconductor wafer including a two-axis lift-rotation motor center pedestal with vacuum capabilities. Wafers are subjected to a pressure differential between the top surface and bottom surface so that sufficient force prevents the wafer from moving during processing, the pressure differential generated by applying a decreased pressure to the back side of the wafer through interface with the motor assembly.

Description

Central base of integrated two-axis lifting rotary motor in multi-wafer rotating rack ALD

Embodiments of the present invention generally relate to apparatus and methods for holding a substrate during processing. In particular, embodiments of the present invention are directed to apparatus and methods that use a pressure differential to hold a substrate on a pedestal under large acceleration forces.

In some CVD and ALD processing chambers, a substrate, also referred to herein as a wafer, moves relative to the precursor injector and/or heater assembly. If the motion produces an acceleration force greater than the friction, the wafer may become displaced, causing damage or related problems. Off-axis wafers can be slid at high acceleration/deceleration on a moving/rotating pedestal. Friction from the weight of the wafer itself may not be sufficient to hold the wafer on a tool that seeks higher throughput.

To prevent rotational forces from moving the wafer during processing, additional hardware can be used to hold or clamp the wafer in place. Additional hardware may be expensive, difficult to install, difficult to use, and/or cause damage to the wafer during use.

Therefore, there is a need in the art to be able to protect the wafer during processing. The need for methods and apparatus in place to prevent accidental damage to wafers or hardware.

One or more embodiments of the present disclosure are directed to a motor component that includes a motor housing having a top and a bottom. The drive shaft extends a distance from the top of the motor housing and has a cavity in the drive shaft. The first motor is within the motor housing to rotate the drive shaft within the motor housing about a central axis. A second motor is adjacent the bottom of the motor housing and the second motor is in communication with at least one rail within the motor housing to move the first motor and the hollow shaft along the central axis.

An additional embodiment of the present invention is directed to a motor component that includes a motor housing, a drive shaft, a first motor, a second motor, a sealed housing, and a water jacket. The motor housing has a top and a bottom. The drive shaft extends a distance from the top of the motor housing. The drive shaft has a cavity in the drive shaft, the cavity having at least one conduit forming a fluid connection to the cavity. The first motor is within the motor housing to rotate the drive shaft within the motor housing about a central axis. A second motor is adjacent the bottom of the motor housing and the second motor is in communication with at least one rail within the motor housing to move the first motor and the hollow shaft along the central axis. The sealed housing is within the motor housing and has a gas space within the sealed housing. The sealed housing is located around a portion of the drive shaft. The gas space is in fluid communication with the cavity in the drive shaft through at least one conduit. The water jacket is in contact with a lower portion of the drive shaft partially surrounded by the sealed housing.

A further embodiment of the present invention is directed to a processing chamber in a processing chamber At least one gas distribution element is contained within the chamber. The base member is located below the at least one gas distribution member, and the base member includes a top surface, a bottom surface, and at least one groove in the top surface for supporting the wafer. The motor component includes a motor housing, a drive shaft, a first motor, and a second motor. The motor housing has a top and a bottom. The drive shaft extends a distance from the top of the motor housing and has a cavity in the drive shaft. The first motor is within the motor housing to rotate the drive shaft within the motor housing about a central axis. The second motor is adjacent to the bottom of the motor housing. A second motor is in communication with at least one rail within the motor housing to move the first motor and the hollow shaft along the central axis to move the base member proximate or away from the at least one gas distribution member. At least one passage extends between a bottom surface of at least one of the base members and a cavity in the drive shaft, wherein the vacuum formed in the cavity of the drive shaft passes through the at least one passage and the recess in the base member Fluid communication.

100‧‧‧Processing chamber

102‧‧‧Reaction area

110‧‧‧ gas distribution components

111‧‧‧ gas pipeline

112‧‧‧ arrow

113‧‧‧ arrow

115‧‧‧ inner edge

116‧‧‧ outer edge

120‧‧‧ wafer

121‧‧‧ top surface

122‧‧‧ outer peripheral edge

123‧‧‧ bottom surface

127‧‧‧ Path

130‧‧‧Base components

131‧‧‧ top surface

132‧‧‧ bottom surface

133‧‧‧ Groove

134‧‧‧Step area

134a‧‧‧First step area

134b‧‧‧second step area

134c‧‧‧ third step area

135‧‧‧ bottom

137‧‧‧Central Department

140‧‧‧ channel

140a‧‧‧Part I

140b‧‧‧Part II

141‧‧‧Connector

142‧‧‧Connector

146‧‧‧Trenches/pipes

147‧‧‧ hole

148‧‧‧ plug

149‧‧‧Support

150‧‧‧heating components

160‧‧‧Drive shaft

161‧‧‧ cavity

162‧‧‧ valve

165‧‧‧vacuum source

171‧‧‧ Valve

173‧‧‧Remove the clamping chamber

175‧‧‧Remove the clamping air supply

200‧‧‧Motor components

202‧‧‧Motor housing

203‧‧‧ top

204‧‧‧ bottom

205‧‧‧ top

206‧‧‧ bottom

207‧‧‧ side

210‧‧‧ drive shaft

211‧‧‧ central axis

212‧‧‧ cavity

213‧‧‧ Subject

215‧‧‧ Pipes

217‧‧‧ top

220‧‧‧First motor

222‧‧‧Motor/Axis Interface

230‧‧‧second electric motor

232‧‧‧rails

234‧‧‧ nuts

236‧‧‧ screws

240‧‧‧ Sealed housing

241‧‧‧vacuum source

242‧‧‧Sealed casing through opening

243‧‧‧ gas space

245‧‧‧O-ring

260‧‧‧ bellows

270‧‧‧ water jacket

272‧‧‧Rotary joint

274‧‧‧Sheath/joint interface

275‧‧‧Inlet pipe

276‧‧‧Export tube

277‧‧‧Feed conduit

280‧‧‧Torque plate

282‧‧‧reflector

Thus, a more particular description of the present invention, which is briefly described above, may be obtained by reference to the embodiments herein. The drawings show only typical embodiments of the present invention and thus are not to be considered as limiting the scope of

1 shows a partial cross-sectional view of a processing chamber in accordance with one or more embodiments of the present disclosure; and FIG. 2 shows a view of a portion of a gas distribution element in accordance with one or more embodiments of the present disclosure; Processing chamber according to one or more embodiments of the present disclosure A partial cross-sectional view of a chamber; FIG. 4 illustrates a partial cross-sectional view of a processing chamber in accordance with one or more embodiments of the present disclosure; and FIG. 5 illustrates a base member having a visible vacuum channel in accordance with one or more embodiments of the present disclosure. 6 is a perspective view of a base member according to one or more embodiments of the present disclosure; and FIG. 7 illustrates a vacuum passage according to one or more embodiments of the present disclosure. A partial cross-sectional view of a base member; FIG. 8 illustrates a partial cross-sectional view of a base member having a vacuum passage in accordance with one or more embodiments of the present disclosure; and FIG. 9 illustrates a base in accordance with one or more embodiments of the present disclosure A partial cross-sectional view of the component; and FIG. 10 illustrates a cross-sectional view of the motor component in accordance with one or more embodiments of the present disclosure.

For ease of understanding, the same element symbols have been used to designate the same elements that are common to the figures, where possible. It is contemplated that elements and features of one embodiment may be beneficially utilized in other embodiments without further recitation.

Embodiments of the present invention provide methods and apparatus that can hold wafers in place during processing to prevent or minimize accidental damage to wafers and hardware. The specific embodiment of the present invention is directed to an apparatus and method for generating a pressure differential formed from a unique precursor injector design that is sufficient at high rotational speeds The amount by which the wafer is held in place. As used in the specification and the appended claims, the terms "wafer", "substrate" and the like are used interchangeably. In some embodiments, the wafer is a rigid, discrete substrate.

In some spatial ALD chambers, the precursors for deposition are injected very close to the wafer surface. To create aerodynamics, the injector tubes are independently controlled at a higher pressure than the surrounding chambers. By creating a pressure differential between the front side of the wafer and the back side of the wafer, a positive pressure sufficient to maintain a relatively large acceleration force against the wafer can be generated.

The embodiment of the present invention is directed to the use of a differential pressure for holding a substrate (wafer) on a susceptor under a large acceleration force. The large acceleration force is due to the high rotational speed, while in the rotating rack type processing chamber a high rotational speed is experienced due to the larger batch and processing speed for higher wafer throughput or higher reciprocating motion.

In some embodiments, the wafer is placed in a shallow recess on the pedestal below the injector assembly. The pedestal can provide heat transfer, improved aerodynamics, and/or the pedestal can serve as a carrier for the substrate.

Embodiments of the present invention are directed to a pedestal having a slanted hole from the inner diameter of the bottom of the susceptor up to the wafer pocket to obtain a vacuum. The base can be coupled to the vacuum source by a rotating shaft and a rotary motor below the shaft. If the susceptor is made of graphite coated with silicon carbide (SiC), additional holes may be provided from the top or bottom of the susceptor for better penetration of the SiC coating, for example with an aperture Every three times the interval. The excess holes are plugged for vacuum. The graphite plug can be press fit before the SiC coating, and then the susceptor is coated with SiC. In some embodiments, for more corrosive applications, in order to use SiC A better graphite seal can be applied to the threaded SiC coated plug and the second SiC coating on the SiC coated susceptor.

FIG. 1 illustrates a portion of a processing chamber 100 in accordance with one or more embodiments of the present disclosure. The processing chamber 100 includes at least one gas distribution element 110 to distribute the reactant gases to the chamber. The embodiment shown in Figure 1 has a single gas distribution element 110, but those skilled in the art will appreciate that any suitable number of gas distribution elements can be present. There may be multiple elements with spaces between the elements or with little spacing between the elements. For example, in some embodiments, there may be multiple gas distribution elements 110 positioned adjacent one another such that wafer 120 effectively experiences a consistently repeating gas flow.

While various types of gas distribution elements 110 (eg, showerheads) can be used, the embodiment shown in FIG. 1 shows several substantially parallel gas conduits 111 for ease of description. As used in this specification and the appended claims, the term "substantially parallel" means that the axis of extension of the gas conduit 111 extends in the same general direction. The parallelism of the gas conduit 111 may be slightly insufficient. However, those skilled in the art will appreciate that the rotating rack-type processing chamber can be rotated about a central axis that is offset from the central axis of the wafer. In this configuration, gas conduits 111 that are generally non-parallel may be useful. Referring to Figure 2, the gas distribution element 110 can be a pie-shaped segment in which the gas conduit 111 extends from the inner edge 115 of the pie shape toward the outer edge 116 of the pie. The shape of the gas conduit 111 can also vary. In some embodiments, the gas conduit 111 has a substantially uniform width along the length of the conduit that extends from the inner edge 115 to the outer edge 116. In some embodiments, the width W of the gas conduit 111 increases along the length L of the conduit extending from the inner edge 115 to the outer edge 116. This situation is shown in Figure 2, The gas conduit 111 has a smaller width near the inner edge 115 and a wider width near the outer edge 116. According to some embodiments, the aspect ratio of the width variation may be equal to the radial difference in the position such that the edge of each tube extends from the same point. This allows all points of the wafer to have approximately equal residence times under the gas conduit. In other words, each pipe width can vary according to the distance from the center of rotation of the susceptor.

Referring back to FIG. 1, the plurality of gas conduits 111 can include at least one first reactive gas A conduit, at least one second reactive gas B conduit, at least one purge gas P conduit, and/or at least one vacuum V conduit. Gas flowing out of the first reaction gas A pipe, the second reaction gas B pipe, and the purge gas P pipe is directed toward the top surface 121 of the wafer 120. Airflow is shown by arrow 112. Some of the airflow moves horizontally across the surface 121 of the wafer 120 and moves up and out of the processing region by the vacuum V-duct as indicated by arrow 113. The substrate moving from left to right will be sequentially exposed to each process gas to form a layer on the surface of the substrate. The substrate can be in a single wafer processing system in which the substrate moves in a reciprocating manner under the gas distribution element; or the substrate can be in a rotating rack type system in which one or more substrates surround the gas conduit The center axis rotates. 2 illustrates a portion of a rotating rack type system in accordance with one or more embodiments of the present disclosure. For the orientation of Figure 2, the process gas can be considered to be the plane out of the drawing. The substrate following path 127 will be sequentially exposed to each process gas. Path 127 is shown as enclosing an arc of about 90°, but those skilled in the art will appreciate that path 127 can be any length and any portion of the curved path.

Figure 3 illustrates a cross-sectional view of one or more embodiments of the present disclosure. The cross-sectional portion of the gas distribution element 110 can be envisioned as being along the net, for example, in Figure 2. The length of the gas port is obtained. The base member 130 can be located below the gas distribution assembly 110. The base member 130 includes a top surface 131, a bottom surface 132, and at least one groove 133 in the top surface 131. Depending on the shape and size of the wafer 120 being processed, the recess 133 can be any suitable shape and size. In the illustrated embodiment, the groove 133 has two stepped regions 134 that surround the outer peripheral edge of the groove 133. The stepped region 134 can be sized to support the outer peripheral edge 122 of the wafer 120. The amount of outer peripheral edge 122 of wafer 120 supported by stepped region 134 may vary depending on, for example, the thickness of the wafer and the presence of features already on back side 123 of the wafer.

In some embodiments, the recess 133 in the top surface 131 of the base member 130 can be sized such that the wafer 120 supported in the recess 133 has substantially coplanar with the top surface 131 of the base member 130. Top surface 121. As used in this specification and the appended claims, the term "substantially coplanar" means that the top surface of the wafer is coplanar with the top surface of the base member within a tolerance of ± 0.2 mm. In some embodiments, the top surface of the wafer is coplanar with the top surface of the base member within a tolerance of ±0.15 mm, ±0.10 mm, or ±0.05 mm.

The bottom 135 of the recess has at least one channel 140 that extends from the bottom of the recess 133 through the base member 130 to the drive shaft 160 of the base member 130. Channel 140 can be of any suitable shape and size, and channel 140 forms fluid communication between groove 133 and drive shaft 160. The channel 140 shown in Figure 3 is angled relative to the bottom of the groove. In some embodiments, the channel 140 includes more than one branch in fluid communication with the groove. For example, a major portion of the channel 140 can extend parallel to the top or bottom surface of the pedestal, and the channel The main portion of 140 can be connected to a second branch that is turned relative to the main portion of the passage. The drive shaft 160 can be coupled to a vacuum source 165 that forms a region of reduced pressure (referred to as vacuum) within the cavity 161 of the drive shaft 160. As used in this specification and the appended claims, the term "vacuum" as used in this context means a region having a lower pressure than the pressure of the processing chamber. In some embodiments, the vacuum, or reduced pressure region, has less than about 50 Torr, or less than about 40 Torr, or less than about 30 Torr, or less than about 20 Torr, or less than about 10 Torr, or less than about 5 Torr, Or a pressure of less than about 1 Torr, or less than about 100 milliTorr, or less than about 10 milliTorr.

The cavity 161 can act as a vacuum plenum so that if there is a loss of external vacuum, the vacuum within the cavity 161 can be maintained at a reduced pressure. Channel 140 is in communication with cavity 161 such that vacuum within cavity 161 can attract back side 123 of wafer 120 through channel 140.

In the case of a vacuum or partial vacuum in the recess 133 below the wafer 120, the pressure in the reaction zone 102 above the wafer 120 is greater than the pressure in the recess 133. This differential pressure provides sufficient force to prevent wafer 120 from moving during processing. In one or more embodiments, the pressure in the recess 133 below the wafer 120 is lower than the pressure above the wafer 120 and the pressure in the processing chamber 100.

The pressure from the gas flow emitted by the gas distribution element 110 and applied to the top surface 121 of the wafer 120, along with the reduced pressure below the wafer, helps keep the wafer in place. This has particular utility in rotating rack-type processing chambers in which the wafer is offset from the central axis and rotates about the central axis in the rotating rack-type processing chamber. The centrifugal force associated with the rotation of the base member can cause the wafer to slide away from the central axis. Because the gas pressure from the gas distribution component is relatively true The pressure applied to the backside of the wafer, the differential pressure on the top side of the wafer relative to the bottom side of the wafer helps prevent wafer movement. The gas conduit of the gas distribution element can be simultaneously (eg, simultaneously controlling all of the output conduits - the reactive gas conduit and the purge conduit), in groups (eg, simultaneously controlling all of the first reactive gas conduits) or independently (eg, the leftmost The pipe is controlled independently of adjacent pipes, etc.). As used in this specification and the appended claims, the terms "output conduit", "gas conduit", "gas injector" and the like are used interchangeably to mean a slot, pipe or nozzle type opening, gas. Injection into the processing chamber through these slots, ducts or nozzle type openings. In some embodiments, the first reactive gas conduit, the second reactive gas conduit, and the at least one purge gas conduit are independently controlled. Independent control can be used to provide positive pressure on the top surface of the wafer located in the recess of the base element. In some embodiments, each individual first reactive gas injector, second reactive gas injector, purge gas injector, and pump conduit can be individually and independently controlled.

The differential pressure between the top surface of the wafer and the bottom surface of the wafer can be adjusted by varying parameters such as the pressure of the gas from the gas distribution element, the gas flow rate from the gas distribution assembly, the gas distribution element and the crystal The distance between the circle or the surface of the pedestal and the vacuum pressure described above. As used in this specification and the appended claims, differential pressure is a measure of the pressure above the wafer relative to the pressure below the wafer. The pressure above the wafer is the pressure applied to the wafer surface or the pressure in the reaction zone 102 of the processing chamber 100. The pressure below the wafer is the pressure in the groove, the pressure of the vacuum pressure in the base member 130 on the bottom surface. The magnitude of the differential pressure can directly affect the extent to which the wafer is clamped. In some embodiments, the top surface 121 of the wafer 120 and the bottom surface 123 of the wafer 120 The differential pressure between is greater than about 15 Torr, or greater than about 10 Torr, or greater than about 5 Torr. In one or more embodiments, the differential pressure between the top surface 121 of the wafer 120 and the pressure in the recess 133 is equivalent to a clamping force that is sufficiently large to have a bolt center radius of about 320 mm. A wafer of 300 mm was held at a rotational speed of about 200 rpm.

In some embodiments, as shown in FIG. 3, the processing chamber 100 includes a heating assembly 150. The heating assembly can be located at any suitable location within the processing chamber including, but not limited to, under the base assembly 130 and/or on the opposite side of the base assembly 130 other than the gas distribution assembly 110. Heating element 150 provides sufficient heat to the processing chamber to raise the temperature of wafer 120 to a temperature useful for the process. Suitable heating elements include, but are not limited to, electrical resistance heaters and radiant heaters (e.g., a plurality of lamps) that direct radiant energy toward the bottom surface of the base member 130.

The distance between the gas distribution element 110 and the top surface 121 of the wafer 120 can be adjusted and can have an effect on the differential pressure and the gas flow efficiency from the gas distribution element. If the distance is too large, the gas flow may diffuse outward before encountering the wafer surface, resulting in a lower differential pressure and inefficient atomic layer deposition reaction. If the distance is too small, the gas flow may not flow through the surface to the vacuum orifice of the gas distribution element and may create a large differential pressure. In some embodiments, the gap between the wafer surface and the gas distribution element is in the range of from about 0.5 mm to about 2.0 mm, or in the range of from about 0.7 mm to about 1.5 mm, or from about 0.9 mm to Within a range of about 1.1 mm, or about 1.0 mm.

The recess 133 shown in FIG. 3 supports the wafer 120 around the outer peripheral edge 122 of the wafer 120. Depending on thickness, stiffness and/or vacuum pressure in the groove 133 This arrangement can result in successful clamping of the wafer, preventing or minimizing wafer motion during rotation or movement of the susceptor assembly 130. However, if the wafer is not thick or rigid, or the vacuum pressure in the recess 133 is too low, the wafer 120 may be skewed such that the central portion of the wafer is further away from the gas distribution than the outer peripheral edge 122 of the wafer 120. Component 110.

Figure 4 illustrates another embodiment illustrating the prevention of wafer deflection by providing a larger support surface area. Here, the base member 130 supports the wafer 120 across most of the back side 123. This figure shows a cross-sectional view of the susceptor assembly. The central portion 137 of the base assembly 130 is not free floating, but is connected to the remainder of the base in a different plane than the cross-sectional view. The passage 140 extends from the drive shaft 160, or from the cavity 161 within the drive shaft 160, toward the recess 133. Channel 140 is coupled to trench 146 that extends toward top surface 131 of base member 130. The vacuum clamps the wafer 120 to the susceptor assembly 130 by vacuum through the grooves 146 and 140.

Figure 5 shows a perspective view of a base member 130 similar to the base member of Figure 4. The illustrated base member 130 has a recess 133 having a relatively large stepped region 134 to support an outer peripheral edge 122 (not shown) of the wafer. The groove 133 includes a large passage 140 that connects the groove 146 to a vacuum in the drive shaft. The groove is shown to be shaped like a capital letter θ, which provides a grooved ring having a grooved portion (or transverse groove) that extends across the diameter of the grooved ring. The central portion 137 of the base assembly 130 can be coplanar with the stepped region 134 such that the central portion 137 and the stepped region 134 simultaneously support the wafer.

FIG. 6 illustrates a perspective view of a base member 130 in accordance with one or more embodiments of the present disclosure. Here, the channel 140 is driven from the groove by using the groove 146 in the groove. The moving shaft 160 extends toward a recess 133 connecting the cavity 161, which serves as a vacuum plenum. Channel 140 has a plurality of apertures 147 that connect top surface 131 of base member 130 to channel 140. In some embodiments, there is at least one aperture that extends from one of the top surface 131 of the base member 130 and the bottom surface 132 of the base member 130 to the channel 140. These holes 147 may be created (eg, drilled) during manufacture of the base member to allow the interior of the channel 140 to be coated. For example, in some embodiments, the base member 130 has a tantalum carbide coating. The susceptor element of some embodiments is tantalum carbide coated graphite. Hole 147 allows the tantalum carbide to be coated on channel 140 and subsequently sealed with plug 148. The plug may be made of any suitable material including, but not limited to, tantalum carbide, tantalum carbide coated graphite, a material having a tantalum carbide coating and graphite. After the plug 148 has been inserted into the aperture 147, the base member can be coated with tantalum carbide again to provide an additional seal of the aperture 147. The plug 148 can be press-fitted (eg, friction fit) to the bore 147 by complementary threads, or by some other mechanical connection (eg, epoxy).

During the preparation of the tantalum carbide coated base member 130, the apertures 147 provide a useful passage for the coating channel 140 for the tantalum carbide. The size and spacing of the holes 147 may have an effect on the efficiency of the coating. The apertures 147 can be spaced apart in increments of aperture. For example, if the diameter of the hole is 5 mm, the spacing can be 5x mm, where x is any suitable value. For example, the interval may be 1 time, 2 times, 3 times, 4 times, 5 times, 6 times, 7 times, 8 times, 9 times or 10 times the pore size. The apertures 147 can be located at any suitable point along the length of the channel 140, and the apertures 147 need not be evenly distributed across the length of the channel 140. As shown in FIG. 6, the apertures 147 are concentrated toward the interior of the base member 130 with the channel 140 being remote from the top surface 131 of the base member 130.

Channel 140 can be used to supply vacuum to groove 133 to clamp wafer 120. However, when the wafer is processed, the vacuum may be too strong to easily remove the processed wafer from the recess. Channel 140 can also be used to provide airflow toward the back side of wafer 120 for ease of wafer removal. Thus, a positive pressure is applied to the back side of the wafer to allow the wafer to be easily removed from the susceptor assembly.

Figure 9 shows a schematic view of a base member in accordance with one or more embodiments of the present disclosure. Here, the groove 133 is connected to the passage 140 which leads to the cavity 161 within the drive shaft. Valve 171 is located within passage 140. Valve 171 can allow a fluid connection between passage 140 and cavity 161 through connector 141. If a vacuum, or a region of reduced pressure, is formed in the cavity 161, the valve can connect the cavity 161 to the recess 133 through the connector 141 and the passage 140. Valve 171 can be switched to interrupt the fluid connection between channel 140 and cavity 161. The valve can be placed in a closed position to isolate the passage 140; or to a position in which a connection is formed between the passage 140 and the removal of the clamping plenum 173 by the connector 142. The removal of the clamping plenum 173 is shown in fluid communication with the removal of the clamping gas source 175. The removal of the pinch gas source 175 can comprise any suitable gas including, but not limited to, nitrogen, argon, helium or an inert gas.

FIG. 7 illustrates another embodiment of a base assembly 130. Here, the channel 140 extends from the outer edge of the base member 130 approximately parallel to the bottom of the groove 133. Plug 148 closes the end of channel 140. The first portion 140a of the channel is diverted to the second portion 140b and extends into the drive shaft 160. A conduit 146 extends from the channel 140 into the bottom of the groove 133 around the center of the groove 133. A plurality of mounts 149 extend from the bottom 135 of the recess 133 to the height of the first step in the stepped region 134. A number of mounts 149 provide support for the wafer to prevent or minimize bending. Support 149 They are positioned around the groove with a gap therebetween to allow the vacuum to affect the entire groove.

FIG. 8 illustrates another embodiment of a base assembly 130. Here, the groove includes a plurality of steps that are progressively larger than the height of the initial stepped region 134. The first stepped region 134a has a first height. The second stepped region 134b has a second height that is greater than the first height. The third stepped region 134c has a third height that is greater than the second height. While three stepped regions are illustrated, those skilled in the art will appreciate that any number of stepped regions may be present. In the illustrated embodiment, the heights of the first, second, and third stepped regions increase toward the center of the groove. In some embodiments, the height of the individual stepped regions may be different such that some regions have a greater height than other regions, regardless of the location of the region relative to the center of the groove.

The diameter and height of individual step regions can vary. In some embodiments, the first stepped region 134a has a height in a range from about 10 [mu]m to about 90 [mu]m relative to the initial stepped region 134. When the wafer 120 is placed on the initial stepped region 134a, the first height is measured relative to the initial stepped region 134 even though the initial stepped region 134 is below the level of the top surface 131 of the base member 130. In some embodiments, the first height is in the range of from about 20 [mu]m to about 80 [mu]m, or in the range of from about 30 [mu]m to about 70 [mu]m, or in the range of from about 40 [mu]m to about 60 [mu]m.

In the embodiment shown in FIG. 8, the second stepped region 134b of some embodiments has a height in the range of about 35 [mu]m to about 115 [mu]m, and the height of the second stepped area 134b is greater than the height of the first stepped area 134a. In some embodiments, the second stepped region 134b has a thickness of between about 45 μm and about 105 μm. Within the range, or in the range of from about 55 μm to about 95 μm, or in the range of from about 65 μm to about 85 μm.

In the embodiment shown in FIG. 8, the third stepped region 134c has a height in a range of about 60 [mu]m to about 140 [mu]m, and the height of the third stepped area 134c is greater than the height of the second stepped area 134b. In some embodiments, the third stepped region 134c has a height in a range from about 70 μm to about 130 μm, or in a range from about 80 μm to about 120 μm, or in a range from about 90 μm to about 110 μm.

The height of the support 149 may vary depending on the height of the particular stepped region in which the support is located. Referring to Figure 8, the abutment in the third stepped region is higher than the abutment in the first stepped region. The mount of some embodiments has a height sufficient to substantially coplane the top of the mount with the initial stepped region such that the wafer located in the recess is substantially coplanar with the top surface of the base member.

Vacuum source 165 can be coupled to cavity 161 by valve 162. In the presence of a vacuum loss from vacuum source 165, valve 162 can be used to isolate cavity 161 from vacuum source 165. This allows the cavity 161 to act as a vacuum plenum so that the wafer on the susceptor assembly remains clamped until the vacuum source is reconnected or repaired.

Each of the individual grooves 133 in the base member 130 can include a separate passage 140 and a valve 171. This allows each individual groove 133 to be isolated from the vacuum in the cavity 161. For example, the processed wafer 120 can be rotated to the loading/unloading area of the processing chamber. Valve 171 can be closed or switched to remove clamping plenum 173 to create a positive pressure on the back side of the wafer, allowing the robot to pick up the wafer. After picking up the wafer, the valve can be closed so that the pressure in the groove 133 will be equal to the chamber pressure. A new wafer can be placed into the recess and valve 171 is switched back to allow fluid connection to cavity 161 to clamp the new wafer.

According to one or more embodiments of the present disclosure, the central base on the rotating rack-type base driven by the integrated two-axis motor for lifting and rotating the base can also be used to incorporate, for example, nitrogen or vacuum for clamping/ Remove the clamping wafer. Additionally, some embodiments use water, or coolant, to maintain a seal and use a motor magnet of the wafer and electrical ground during plasma processing.

Referring to Figure 10, a schematic diagram of a motor component 200 for one or more embodiments of the present disclosure is provided. Motor component 200 has a motor housing 202 having a top 203 and a bottom 204. The illustrated motor component 200 includes a bottom portion 206 that may be integrally formed with the side 207 of the outer casing 202 or may be a separate component.

Motor component 200 includes a drive shaft 210 from a top 203 of motor housing 202. The drive shaft 210 includes a body 213 and a cavity 212 in the body. The cavity 212 can be in fluid communication with a gas or vacuum source and can function as a plenum as described further below.

The drive shaft 210 can be made of any suitable material that is capable of supporting the base member during wafer processing while retaining the cavity within the base member. In some embodiments, the drive shaft 210 is made of a material that includes stainless steel. The size of the drive shaft 210 may vary depending, for example, on the size and weight of the base member and other components supported on the base member.

The drive shaft 210 extends a distance D from the motor housing 202. This distance D can be changed or changed before, during and/or after processing. In use, the motor component 200 supports and rotates the base assembly. Drive shaft 210 extends from motor housing 202 The distance D is directly related to the vertical height of the susceptor and any wafer supported on the pedestal.

The drive shaft 210 is in contact with a first motor 220 located within the motor housing 202. The first motor 220 rotates the drive shaft 210 within the motor housing 202 about the central axis 211. The drive shaft 210 can be coupled to the first electric motor by contact, friction or hardware. In the embodiment shown in FIG. 10, the drive shaft 210 is coupled to a motor/shaft interface 222 that is coupled to the first motor 220. The motor/shaft interface 222 can be any suitable material including, but not limited to, stainless steel or aluminum. The material of the motor/shaft interface 222 may have an expansion coefficient similar to that of the drive shaft 210 or the seal housing 240, as described below. The first motor 220 can be any suitable type of motor that can rotate the drive shaft 210. In some embodiments, the first motor 220 is a direct drive motor that is directly coupled to the hollow drive shaft 210.

The direct drive motor can be raised and lowered using a combination of a ball screw motor and two symmetric mechanical guides. In some embodiments, the ball screw is positioned as close as possible to the center to minimize axial tilt. The second motor 230 is positioned adjacent the bottom 204 of the motor housing 202. The second motor 230 can be any suitable type of motor including, but not limited to, a ball screw motor. In the embodiment shown in FIG. 10, the second motor 230 is external to the motor housing 202, but the second motor 230 can also be located within the motor housing. The second motor 230 is in communication with at least one rail 232 within the motor housing 202 to move the first motor 220 and the drive shaft 210 along the length of the central axis 211. Movement along the length of the central axis 211 changes the distance D of the drive shaft 210 from the top 203 of the motor housing 202. Nut 234 is along the second motor The screw 236 is positioned. Rotation of the screw 236 causes the nut 234 to move along the length of the screw 236.

The second motor 230 can be located at any position relative to the central axis 211 of the component 200. In some embodiments, the second motor 230 is positioned as close as possible to the central axis 211 to minimize the rack of the motor assembly during motion. In one or more embodiments, the motor components are circular and the functional components of the second motor 230 (eg, screws, nuts, and rails) are located within 50% of the radius of the motor 220 as measured from the central shaft 211.

In some embodiments, there are at least two symmetrical rails 232 within the motor housing 202. The two rails can be located on either side of the central shaft 211 or on either side of the screw 236. For example, the monorail shown in Figure 10 can be two pieces of nut 234 that are simultaneously in contact.

The motor assembly 200 can also include a sealed housing 240 for a dynamic seal combination on a z-axis θ motor that provides a vacuum conduit for the fast-rotating drive shaft 210, the drive shaft having a bore on its own side. The sealed housing 240 can be located within the motor housing 202 and around at least a portion of the drive shaft 210. The sealed housing 240 of some embodiments is in fluid communication with one or more of a vacuum source 241 or a source of gas (not shown). A vacuum source 241 or a source of gas may be coupled to the sealed housing through opening 242. In some embodiments, the sealed housing 240 includes a gas space 243 for holding a gas or vacuum. When the vacuum source 241 is connected to the sealed housing 240, the gas space 243 is under vacuum. When a gas source (not shown) is connected to the sealed casing 240, the gas space 243 can hold the gas.

The drive shaft 210 as shown in FIG. 10 may include at least one conduit 215 at the cavity 212 of the drive shaft and the sealed housing 240 A fluid connection is formed between the gas spaces 243. The sealed housing 240 includes at least one O-ring 245 to form a hermetic seal between the sealed housing 240 and the drive shaft 210. In the embodiment shown in FIG. 10, there are two O-rings 245 shown positioned above and below the conduit 215. The O-ring 245 helps ensure a hermetic seal while allowing gas to flow from the cavity 212 through the conduit 215 into the gas space 243 of the sealed housing 240 and ultimately out to the vacuum source 241. When a gas source is used instead of a vacuum source, the airflow path is reversed.

In some embodiments, at least one of the drive shafts 215 extends generally perpendicular to the central axis 211. As used in this specification and the appended claims, the term "substantially perpendicular" as used in this context means that the angle of the axis of the conduit 215 relative to the central axis 211 is greater than or equal to about 45 degrees. In some embodiments, the angle of the pipe axis relative to the central axis 211 is greater than about 15 degrees, 20 degrees, 25 degrees, 30 degrees, 35 degrees, 40 degrees, 45 degrees, 50 degrees, 55 degrees, 60 degrees, 65 degrees, 70 degrees, 75 degrees, 80 degrees or 85 degrees. In one or more embodiments, the angle of the conduit axis relative to the central axis is in the range of from about 85 to about 90 degrees, or in the range of from about 80 degrees to about 90 degrees.

The number of conduits 215 formed in drive shaft 210 can be any suitable number. In some embodiments, one, two, three, four, five, six, seven, eight or more separate channels extend through the body 213 of the drive shaft 210, in the cavity 212 and the gas A fluid connection is formed between the spaces 243. In some embodiments, there are four laterally drilled conduits through the body 213. In one or more embodiments, a single area 20 mm diameter vacuum is supplied to the pedestal and provides a circular shape between the shaft lip seal (top O-ring 245) and the square seal (lower O-ring 245). The shaft is received in the pocket and then received through four side holes or tubes. In some embodiments, the cavity in the drive shaft 210 has a diameter of 100 mm and the cavity can be used as a vacuum reservoir for holding the remainder of the wafer clamped during wafer exchange.

Vacuum isolation may be assisted or implemented using a combination of stainless steel bellows 260 and/or a dynamic lip seal (O-ring 245) housed in sealed housing 240. To further isolate the gas space 243 of the sealed housing 240 from the processing environment, the bellows 260 is positioned between the sealed housing and the top 205 of the motor housing 202. The top 205 of the motor housing 202 can be coupled to the side 207 of the motor housing using any suitable method included. The top portion 205 can be a separate component that is mechanically attached to the side 207 or can be integrally formed with the side 207. The bellows 260 expands and contracts along the length of the central shaft 211 during movement of the motor 220, the drive shaft 210, and the seal housing 240.

The rotor shaft supporting the base can be cooled to prevent heat from being conducted to the directly driven motor magnet and causing demagnetization. The first motor 220, which may be a direct drive motor, may be water cooled by flowing water through the sealed housing 240. Additionally, according to the embodiment, because the susceptor is often heated to a process temperature of up to 550 °C, the bottom end of the drive shaft 210 is cooled to prevent damage to the dynamic seal and motor magnet due to overheating. This cooling is accomplished by attaching, contacting or bolting the water rotary joint, or water jacket 270, under the drive shaft 210, wherein the water flows upwardly through the press-fit connection of the water jacket to the shaft to the seal. In some embodiments, the water jacket 270 is in contact with the bottom of the drive shaft 210 through the motor/shaft interface 222. The water jacket 270 can be coupled to the lower portion of the drive shaft 210, but a simple contact of the water jacket 270 and the drive shaft 210 can be sufficient to cool the drive shaft 210. The water jacket 270 may also rotate during rotation of the drive shaft 210 or may remain stationary. In some embodiments The sealed housing 240 is positioned around a portion of the water jacket 270.

While the coolant is referred to as a water jacket, those skilled in the art will appreciate that any type of coolant can be used. For example, automotive antifreeze can be used in place of water. The water jacket 270 is typically made of a material that is a good conductor of heat. In some embodiments, the water jacket is made of aluminum.

In the embodiment shown in FIG. 10, the water jacket 270 is coupled to the swivel joint 272 by a jacket/joint interface 274. The rotary joint 272 can remain stationary during rotation of the drive shaft 210 while the water jacket 270 rotates about the drive shaft 210. This can be accomplished by a coolant (gas or liquid) flowing through the inlet tube 275 into the fixed rotary joint 272. The coolant then flows upwardly to the jacket/joint interface 274 where the tubular members are connected to respective ones of the water jackets 270, and then the coolant exits the outlet tubes 276.

The electrical multi-conductor slip ring can be bolted under the water rotary joint to take the wires up into the pedestal. Electrical connections may be made from the base through the slip ring mounted to the bottom of the shaft through the drive shaft 210. The slip ring and motor/shaft interface 222 (also referred to as motor/shaft joint) can be the same component or different components. A plurality of thermocouple wires for inspecting the susceptor temperature in the plurality of regions and a plurality of wires for grounding the wafer on the pedestal may pass through the feed conduit 277 through the drive shaft 210 and the water jacket 270.

Some embodiments of the present disclosure are directed to a base member that includes a motor member 200 (such as the motor assembly of FIG. 10) and a base that communicates with the top 217 of the drive shaft 210. In some embodiments, the torque plate 280 is coupled to the top 217 of the drive shaft 210. Torque plate 280 forms an interface between drive shaft 210 and base member 130. In some embodiments, as in Figure 10 As shown, the reflector 282 is positioned between the torque plate 280 and the base member 130. In some embodiments, heat from the base member 130 is progressively reduced using a plurality of stainless steel plates (reflecting plates 282) stacked in parallel. Heat from the heater around the shaft (see Figure 3) can be reflected back using the 17-4 PH steel reflector shield around the drive shaft to keep the shaft cool. In some embodiments, the residual heat conducted through the susceptor is reduced by water-cooling the shaft using a water swivel under the shaft using a water jacket as previously described. Water, or coolant, can be drilled through a gun in the thickness of the drive shaft or by bolting a water rotary joint under the aluminum sleeve to the motor shaft.

In some embodiments, an angled hole is provided from the inner diameter of the bottom of the base up to the respective wafer pocket for clamping/removing the clamp. The slanted holes can be joined to the hollow drive shaft at high temperatures using a faceless sealed finishing plate to prevent vacuum leakage. In the case of external vacuum loss, the hollow shaft can act as a vacuum chamber.

In some embodiments, as seen in FIGS. 5 and 6, the base member 130 includes a plurality of grooves 133 in the top surface 131 of the base member 130. As shown in FIGS. 6-8, a plurality of channels 140 extend from the cavity 212 of the drive shaft 210 to a recess 133 in the base assembly 130. In some embodiments, as shown in Figure 9, the channel 140 can include a valve in fluid communication with the channel. Multi-zone vacuum clamping enables independent control of each wafer pocket on the rotating rack, which facilitates wafer exchange. Each vacuum region is connected through a rotor shaft supporting a base, which may be a conduit for various fluids and feeds up to the base, for example, nitrogen for cleaning or wafer removal clamping; Zone vacuum can be applied to clamping.

The substrate used in the embodiments of the present invention may be any suitable substrate. In a detailed embodiment, the substrate is a rigid, discrete, and generally planar base board. As used in the specification and the appended claims, the term "discrete" when referring to a substrate means that the substrate has a fixed size. The substrate of a specific embodiment is a semiconductor wafer, such as a 200 mm or 300 mm diameter germanium wafer.

As used in the specification and the appended claims, the terms "reactive gas", "reaction precursor", "first precursor", "second precursor", etc., are meant to be capable of interacting with a substrate surface or a substrate surface. The layer reacts with a gas or gas species.

In some embodiments, one or more layers can be formed during a plasma enhanced atomic layer deposition (PEALD) process. In some processes, the use of plasma provides sufficient energy to promote the species to an excited state in which the surface reaction becomes good and possible. Introducing the plasma into the process can be continuous or pulsed. In some embodiments, sequential pulses of precursor (or reactive gas) and plasma are used to treat the layer. In some embodiments, the reactants can be ionized locally (ie, within the treatment zone) or distally (ie, outside of the treatment zone). In some embodiments, distal ionization can occur upstream of the deposition chamber such that ions or other high energy or luminescent species are not in direct contact with the deposited film. In some PEALD processes, plasma is generated from outside the processing chamber, such as by a remote plasma generator system. The plasma can be produced by any suitable plasma generation process or technique known to those skilled in the art. For example, the plasma can be generated by one or more of a microwave (MW) frequency generator or a radio frequency (RF) generator. The frequency of the plasma can be tuned depending on the particular reaction species being used. Suitable frequencies include, but are not limited to, 2MHz, 13.56MHz 40MHz, 60MHz and 100MHz. Although plasma can be used during the deposition process disclosed herein, plasma may not be necessary. In fact, other embodiments involve a deposition process under very mild conditions without plasma.

According to one or more embodiments, the substrate undergoes processing prior to forming the layer and/or after forming the layer. This process can be performed in the same chamber or in one or more separate processing chambers. In some embodiments, the substrate is moved from the first chamber to the separate second chamber for further processing. The substrate can be moved directly from the first chamber to the separate processing chamber, or the substrate can be moved from the first chamber to the one or more transfer chambers and subsequently moved to the separate processing chamber. Thus, the processing device can include a plurality of chambers in communication with the transfer station. Such devices may be referred to as "cluster tools" or "cluster systems", and the like.

Typically, a cluster tool is a modular system that includes a plurality of chambers that perform various functions including substrate center viewing and orientation, degassing, annealing, deposition, and/or etching. According to one or more embodiments, the cluster tool includes at least a first chamber and a central transfer chamber. The central transfer chamber can accommodate a robot that can reciprocate the substrate between or among the processing chamber and the load lock chamber. The transfer chamber is typically maintained under vacuum and provides an intermediate stage for reciprocating transfer of the substrate from one chamber to another and/or reciprocatingly to a load lock chamber located at the front end of the cluster tool . Two well-known clustering tools that may be suitable for this case are the Centura and Endura clustering tools, which are available from Applied Materials, Inc. of Santa Clara, Calif. A detail of this hierarchical vacuum substrate processing apparatus is disclosed in Tepman et al., entitled "Staged-Vacuum Wafer Processing Apparatus and Method", published on February 16, 1993. U.S. Patent No. 5,186,718. However, for the purpose of performing the specific steps of the process as described herein, the precise arrangement and combination of chambers can be varied. Other processing chambers that may be used include, but are not limited to, cyclical layer deposition (CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor phase Physical vapor deposition (PVD), etching, pre-cleaning, chemical cleaning, heat treatment such as rapid thermal process (RTP), plasma nitridation, degassing, orientation, hydroxylation, or other substrate processes. By performing the various processes in the chamber on the cluster tool, surface contamination of the substrate by atmospheric impurities can be avoided and there is no oxidation prior to deposition of the 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 as the substrate moves from one chamber to the next. The transfer chamber is therefore under vacuum and "vacuum" under vacuum pressure. An inert gas may be present in the processing chamber or in the transfer chamber. In some embodiments, an inert gas is used as the purge gas to remove some or all of the reactants after forming a layer of tantalum on the surface of the substrate. According to one or more embodiments, a purge gas is injected at the outlet of the deposition chamber to prevent reactants from moving from the deposition chamber to the transfer chamber and/or additional processing chamber. Therefore, the flow of the inert gas forms a curtain at the exit of the chamber.

The substrate can be processed in a single substrate deposition chamber where a single substrate is loaded, processed, and unloaded, after which another substrate is processed. The substrate can also be processed in a continuous manner like a conveyor belt system, wherein a plurality of substrates are separately loaded into the first portion of the chamber, moved through the chamber and unloaded from the second portion of the chamber. The shape of the chamber and associated conveyor system can form a straight path or a curved path . Additionally, the processing chamber can be a rotating rack in which a plurality of substrates are moved about a central axis and exposed through a rotating rack path to deposition, etching, annealing, cleaning, and the like.

The substrate can be heated or cooled during processing. This heating or cooling can be accomplished by any suitable method including, but not limited to, changing the temperature of the substrate support and flowing a heating or cooling gas to the surface of the substrate. In some embodiments, the substrate support includes a heater/cooler that can be controlled to conductively change the temperature of the substrate. In one or more embodiments, the gas (reaction gas or inert gas) used is heated or cooled to locally change the substrate temperature. In some embodiments, the heater/cooler is located within the chamber adjacent the surface of the substrate to convectively change the substrate temperature.

The substrate can also be fixed or rotated during processing. The rotating substrate can be rotated continuously or in discrete steps. For example, the substrate can be rotated throughout the process, or the substrate can be rotated a small amount between exposure to different reaction or purge gases. Rotating the substrate (continuously or stepwise) during processing can help produce more uniform deposition or etching by minimizing effects such as local variability in gas flow geometry.

Although the present invention has been described with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and changes can be made in the method and apparatus of the present invention without departing from the spirit and scope of the invention. Therefore, the present invention is intended to cover modifications and variations within the scope of the appended claims.

130‧‧‧Base components

200‧‧‧Motor components

202‧‧‧Motor housing

203‧‧‧ top

204‧‧‧ bottom

205‧‧‧ top

206‧‧‧ bottom

207‧‧‧ side

210‧‧‧ drive shaft

211‧‧‧ central axis

212‧‧‧ cavity

213‧‧‧ Subject

215‧‧‧ Pipes

217‧‧‧ top

220‧‧‧First motor

222‧‧‧Motor/Axis Interface

230‧‧‧second electric motor

232‧‧‧rails

234‧‧‧ nuts

236‧‧‧ screws

240‧‧‧ Sealed housing

241‧‧‧vacuum source

242‧‧‧Sealed casing through opening

243‧‧‧ gas space

245‧‧‧O-ring

260‧‧‧ bellows

270‧‧‧ water jacket

272‧‧‧Rotary joint

274‧‧‧Sheath/joint interface

275‧‧‧Inlet pipe

276‧‧‧Export tube

277‧‧‧Feed conduit

280‧‧‧Torque plate

282‧‧‧reflector

Claims (20)

A motor component comprising: a motor housing having a top portion and a bottom portion; a drive shaft extending a distance from the top of the motor housing and having a cavity in the drive shaft; a first motor in the motor housing a drive shaft that rotates within the motor housing about a central axis; and a second motor adjacent the bottom of the motor housing, and the second motor and at least one rail within the motor housing Communicating to move the first motor and the hollow shaft along the central axis. The motor component of claim 1 further comprising a sealed housing within the motor housing, the sealed housing being located about a portion of the drive shaft. The motor component of claim 2, wherein the sealed housing is in fluid communication with a vacuum source. The motor component of claim 2, wherein the drive shaft includes at least one conduit that forms a fluid connection between the cavity of the drive shaft and the seal housing. The motor component of claim 4, wherein the at least one conduit extends in a direction substantially perpendicular to the central axis. The motor component of claim 4, wherein the at least one conduit comprises four conduits. The motor component of claim 4, wherein the sealed housing includes an O-ring for forming a hermetic seal between the sealed housing and the drive shaft. The motor component of claim 1, wherein the first motor is a direct drive motor. The motor component of claim 1, wherein the second motor is a ball screw motor and there are at least two symmetric rails for moving the hollow shaft and the first motor. The motor component of claim 2, further comprising a water jacket in contact with the lower portion of the drive shaft. The motor component of claim 10, wherein the sealed housing is located around a portion of the water jacket. A base member comprising: the motor member of claim 1; and a base in communication with the top of the drive shaft. The base member of claim 12, further comprising a torque plate that forms an interface between the drive shaft and the base. The base member of claim 13, further comprising a reflector between the torque plate and the base. The susceptor element of claim 12, wherein the pedestal includes a plurality of grooves in a top surface of the pedestal. The base member of claim 15 further comprising a plurality of passages extending from the cavity of the drive shaft to the recess in the base. The base member of claim 16, further comprising a valve in fluid communication with the passage. A motor component comprising: a motor housing having a top portion and a bottom portion; a drive shaft extending a distance from the top of the motor housing, the drive shaft having a cavity in the drive shaft, the cavity having a cavity formed therein a fluidly connected at least one conduit of the cavity; a first motor within the motor housing for rotating the drive shaft within the motor housing about a central axis; a second motor adjacent to the motor The bottom of the outer casing, and the second electric motor is in communication with at least one rail within the outer casing of the motor to The central shaft moves the first motor and the hollow shaft; a sealed housing within the motor housing, the sealed housing having a gas space in the sealed housing and located around a portion of the drive shaft, the gas space The cavity is in fluid communication with the cavity in the drive shaft through the at least one conduit; and a water jacket in contact with a lower portion of the drive shaft partially surrounded by the seal housing. A base member comprising: the motor member of claim 18; and a torque plate positioned adjacent to the drive shaft; a reflector adjacent the torque plate; and a base adjacent to the reflection a plate comprising a plurality of grooves in a top surface of the base, wherein the base includes a plurality of channels extending from the cavity in the drive shaft to the base The groove. A processing chamber comprising: at least one gas distribution element within the processing chamber; a base member located below the at least one gas distribution member, the base member including a top surface, a bottom surface, and At least one groove for supporting a wafer in the top surface; and a motor assembly comprising: a motor housing having a top portion and a bottom portion; a drive shaft extending a distance from the top of the motor housing and having a cavity in the drive shaft; a first motor within the motor housing for rotating the drive within the motor housing about a central axis a second motor adjacent to the bottom of the motor housing, the second motor being in communication with at least one rail within the motor housing to move the first motor and the hollow shaft along the central axis to thereby approximate Moving the base member away from the at least one gas distribution member; and at least one passage extending between a bottom surface of the at least one groove in the base member and the cavity in the drive shaft, wherein A vacuum formed in the cavity of the drive shaft is in fluid communication with the groove in the base member through the at least one passage.